Onan NHC, NHCV Service Manual

DO GDDD

OPERATOR

AND

SERIES

PARTS CATALOG

FOR

NHC-NHCV

INDUSTRIAL

ENGINES

S/SERVICE

MANUAL

940-0404

11B74

Replaces

Printed

in U.S.A.

2A73

INTRODUCTION

THIS

OPERATOR'S

PERTAINING

YOUR WE

DIAGRAM WHICH TO

ORDERING FOR A NOMINAL

UNIT.

SUGGEST

IT WHEN MAKING EQUIPMENT ADJUSTMENTS OR

TO THE

YOU

PARTS.

MANUAL CONTAINS INFORMATION

OPERATION

KEEP

ACCOMPANIES

ADDITIONAL

CHARGE

THE MANUAL AND THE WIRING

FROM YOUR DISTRIBUTOR.

AND MAINTENANCE OF

EVERY

COPIES

UNIT

ARE

AND

REFER

AVAILABLE

WHEN ORDERING

MODEL, LOCATED TO

ENSURE

FOR SERVICE

SPECIFICATION

ON THE

THE

CORRECT

REPAIR

TO AVOID POSSIBLE PERSONAL INJURY OR

EQUIPMENT DAMAGE, AN AUTHORIZED SER-

VICE REPRESENTATIVE MUST PERFORM ALL

SERVICE.

SERVICE,

REPRESENTATIVE.

PARTS,

UNIT

REMEMBER TO INCLUDE THE

LETTER,

NAMEPLATE.

PART IS

CONTACT YOUR AUTHORIZED

WARNING

AND

SHIPPED

SERIAL

THIS IS

NUMBER

ESSENTIAL

TO YOU.

t. -M

GENERAL

[NFORMATION

This manual contains installation and operation instructions as well as information required for proper

maintenance, adjustment and repair of the engine.

Since the first and most important part of repair work

is the correct diagnosis of the trouble, a troubleshooting chart is included.

Study and follow the instructions carefully. Proper service and maintenance will result in longer engine

life and better performance.

TABLE OF CONTENTS

TITLE PAGE General Information 1

Safety Precautions Specifications 3 Dimensions and Clearances 4 Assembly Torques and Special Tools 5

Engine Troubleshooting 6 Installation Operation Periodic Maintenance Fuel System

7

11

16

Governor System

Ignition System

Battery Charging System 27

Starting System Engine Disassembly .. , ' Parts Catalog

Engine Wiring Diagrams 66

2

13

22

24

30

3

43

5

How to interpret MODEL and SPEC NO.

NHC - MS / 123 A

1

1.

Factory code for general identification purposes.

2.

Specific Type:

3 4

S—MANUAL starting MS—ELECTRIC starting

3. Factory code for optional equipment supplied.

4.

Specification (Spec Letter) advances with factory

production modification.

MANUFACTURER'S

GENERAL

WARRANTY

Manufaciurcr olcrJi lo ihc original purcha^r of Goods foi use. ihc followins warranties, subject lo the nualificaiions indicated:

l.lManufaciurcr »„ranis saiislacioiy performance for a period ot one f

dale each product is placed in service, so longas such producl is installed, operated and serviced in accordance wilh Manufaetuier's written instroctions. I H I.S WAK KAN Y

• IS IN 11EU OF ALI. OTIIER WARRANTIES. EXPRESSKU OR IMPLIED. INCLUDING FITNESS FOR A PARTICULAR PURPOSE.

IblManufaciurcr's liabilily and purchasers'sole remedy for a failure ofGoods to perform

as warranted, and for any andall olher claims arising outof the purchase and use of the Goods including negligence on lhe pari of Manufacturer, shall bc limited to the repair or replacement of Goods returned to Manufacturer's factor,' or one of its Auihori/ed Service Sialions. iransportation prepaid. The cost of any labor included shall be as sneciHed in Manufacturer's writien ittstruciions. MANUFACTURER SHALL IN NO EVENT BE LIABLE FOR INCIDENTAL OR CONS60UENTIAI. DAMAGES.

I'lAII

claims shall he brought to Manufacturer's aiicntion wilhin Thiny (JOI days after

discovery that the Goods failed to perform as warranted, hul in no event shall a cla.n

:cepied after one (I) year from the date such product is placed in service.

No person is authorired to give any other warranly or to assume any olher liability on

Manufacturer's behalf unless made or assumed in writing by an Officer of Manufaciurcr..and no person is auihorired lo give any warranty or assume any liabilities on the Manufaciurcr's behalf unless made or assumed in writing by such Manufacturer.

11

year from lhe

IMPORTANT!

RETURN

WARRANTY

CARD

ATTACHED

TO

UNIT.

The following symbols in this manual signal potentially dangerous conditions to the operator or equip-

ment. Read this manual caretully. Know when these conditions can exist. Then, take necessary steps to protect personnel as well as equipment.

WARNINGl O

warn of

possible

^^y^jgg

nan

1

throughout this manual to

uses

serious

This

symbol refers to

this symbol

personal injury.

possible

equipment damage.

Fuels/electrical equipment, batteries, exhaust gases

and moving parts present potential hazards that could

result in serious, personal injury. Take care in following these recommended procedures.

• Use Extreme Caution Near

•Fuel

And

Diesel

plosive

Do not till fuel tank near unit with engine running. Do not smoke or use open flame near the unit or the tuel tank.

or

fire

Fuel.

hazard

exists.

Gasoline,

A constant potential ex-

Gaseous

surfaces to be damp when handling electrical equipment.

Jewelry is a good conductor ot electricity and should be removed when working on electrical equipment.

Use extreme caution when working on electrical

components. High voltages cause injury ordeath.

Follow all state and local electrical codes. Have all electrical installations pertormed by a qualified licensed electrician.

• Do Not Smoke While

Lead acid batteries emit a highly explosive hydrogen gas that can be ignited by electrical arcing or by smoking.

•

Exhaust

Provide an adequate exhaust system to properly expel discharged gases. Check exhaust system regularly tor leaks. Ensure that exhaust manifolds are secure and not warped.

Be sure the unit is well ventilated.

Gases

Are

Servicing

Toxic

Batteries

Be sure all fuel supplies have a positive shutoff

valve.

Fuel lines must be of steel piping, adequately secured and free from leaks. Do not use copper piping on flexible lines as copper becomes hardened and brittle. Use black pipe on natural gas or gaseous fuels, not on gasoline or diesel fuels.

Piping at the engine should be approved

flexible line.

Have a fire extinguisher nearby. Be sure extinguisher is properly maintained and be familiar with its proper use. Extinguishers rated ABC by the NFPA are appropriate for all applications.

Consult the local fire department for the correct type of extinguisher tor various applications.

• Guard Against

Remove electric power before removing protec-

tive shields or touching electrical equipment. Use

rubber insulative mats placed on dry wood platforms over floors that are metal or concrete when around electrical equipment. Do not wear damp

. clothing (particularly wet shoes) or allow skin

Electric

Shock

•

Keep

• Protect Against

The Unit And Surrounding Area

Remove all oil deposits. Remove all unnecessary grease and oil from the unit. Accumulated grease and oil can cause overheating and subsequent engine damage and may present a potential fire

hazard. Dispose of oily rags. Keep the floor clean and dry.

Moving

Avoid moving parts of the unit. Loose jackets, shirts or sleeves should not be permitted because ot the danger of becoming caught in moving

parts. Make sure all nuts and bolts are secure. Keep

power shields and guards in position.

If adjustments must be made while the unit is running, manifolds, moving parts, etc.

Do not work on this equipment when mentally or physically fatigued.

use extreme caution around hot

Parts.

Clean.

SPECIFICATIONS

Number of Cylinders 2

_

Displacement (cubic inch) 60

Cylinder Bore

Piston Stroke • • • 3 inch Horsepower—NHC (Pressure Cooled) 25 BHP @ 3600 rpm Horsepower—NHCV (Vacu-Flo Cooled) 22.5 BHP @ 3300 rpm Compression Ratio 7.0 to 1

Ventilation Required (cfm @ 3600 rpm) NHC 1080

Oil Capacity 3-1/2 quart Oil Capacity with Filter Change ••• 4 quart Starting ' Electric Ignition • Battery Combustion Air (cfm @ 3600 rpm) : 80 Fuel • • Gasoline (regular grade) Fuel Pump Diaphragm, 4 ft. lift Battery 12 Volt

0

(cfm @ 3600 rpm) NHCV 1200

.: • 3-9/16 in.

TUNE-UP

Spark Plug Gap • 025-inch

. Breaker Point Gap •• .016-inch

Ignition Timing (Fixed), Electric Start.Units ••... 20° BTC

Tappets (Cold) Intake..; .003-inch

Exhaust ; 012-inch

SPECIFICATIONS

DIMENSIONS AND

All clearances given at room temperature of 70° F.

All dimensions in inches unless otherwise specified.

Valve Stem in Guide—Intake 0.0010 Valve Stem in Guide—Exhaust 0.0025 0.0040 Valve Spring Length

Free Length 1.662 Compressed Length 1.375 ^j.

Valve Spring Tension (Ib.)

Open Closed

Valve Seat Bore Diameter

Intake Exhaust

Valve Seat Diameter

Intake Exhaust

Valve Stem Diameter

Intake

Exhaust Valve Guide Diameter (I.D.) Valve Lifter Diameter

Valve Lifter Bore Valve Seat Interference Width Valve Face Angle Valve Seat Angle Valve Interference Angle

Crankshaft Main Bearing Crankshaft End Play Camshaft Bearing Camshaft End Play Camshaft Lift Camshaft Bearing Diameter Camshaft Journal Diameter

Rod Bearing (Forged Rod) .- • Connecting Rod End Play (Ductile Iron) Timing Gear Backlash Oil Pump Gear Backlash

Piston to Cylinder, Strut Type (Measured below oil-controlling

90° from pin) Clearance Piston Pin Diameter Piston Pin in Piston Piston Pin in Rod .• Piston Ring Groove Width

TUP 1 : Top 2

Top 3 Piston Ring Gap in Cylinder Piston Ring Side Clearance (Top compression ring only)

Crankshaft Main Bearing Journal—Standard Size Main Bearing Diameter : Main Bearing Clearance

Crankshaft Rod Bearing Journal—Standai'd Size Cylinder Bore—Standard Size

CLEARANCES

Minimum Maximum

u.OO^b

71 38

1.5645 1.5655

1.2510 1.2520

1.569 1.570

1.255 1.256

0.3425 0.3430

0.3410 0.3415

0.344

0.7575

0.7505 1/32 3/64

0.0025 . 0.0038

0.005

0.0015

0.003

1.3760 1.3770

1.3740

0.0005 0.0023

0.002 0.016

0.002

ring—

0.0015 0.0035

0.7500 Thumb Push HI

0.0001

0.0955 0.0965

0.0955

0.1880 0.1890

0.010 0.020

1.9992

2.0015

0.0015 0.0043

1.6252

3.5625 3.563b

79 42

0.346

0.7480

0.7515

44" 45°

1°

0.009

0.0030

0.3UO

1.374b

0.003

0.005

0.7502

0.0005

0.0965

0.006

2.0000

2.0040

1.6260

—

ASSEMBLY

TORQUES

Assembly torques as given here require the use of a torque wrench. These assembly torques will assure proper tightness without danger of stripping the threads. If a torque wrench is not available, you will

have.to estimate the degree of tightness necessary for

the

stud,

nut or screw being installed and tighten accordingly. Be careful notto strip the threads. Check all studs, nuts and screws often with the engine Tighten as needed to prevent them from working loose.

TORQUE SPECIFICATIONS Ft.-Lb.

Cylinder Head Nuts 17-19 Rear Bearing Plate 25-28 Connecting Rod Bolt 27-29

Flywheel Capscrew 35-40

Starter Mounting Bracket to

Oil Base Screws 43-48 Gear Case Cover 8-10 Oil Pump 7-9 Other 3/8 Cylinder Block Nuts 18-23;.

Intake Manifold 18-20 Exhaust Manifold 10-12

cold.

SPECIAL

These tools are available from Onan to aid service and

repairwork. Crankshaft Gear Pulling Ring .420-0248

Flywheel Puller... 420-0100 Combination Bearing Remover,

Main and Cam 420-0325

Combination Bearing Driver,

Main and Cam 420-0324 Valve Guide Driver 420-0300 Valve Seat Driver 420-0308 Valve Seat Staker

Intake : 420-0309

Exhaust 420-0310 Valve Seat Cutter 420-0311 Oil Seal Guide and Driver

Bearing Plate 420-0181

Gear Cover 420-0313

Timing Advance Mechanism

Cover Driver 420-0296 Piston Ring Spreader 420-0146 Piston Groove Cleaner 420-0332

TOOLS

s

a

• • • •

• • •

•

o

e

• •

STARTING SYSTEM

Loose or Corroded Battery Connection Low or Discharged Battery

Faulty Starter Faulty Start Solenoid

IGNITION SYSTEM

e

Ignition Timing Wrong Wrong Spark Plug Gap

Worn Points or Improper Gap Setting

Bad Ignition Coil or Condenser Faulty Spark Plug Wires

e

• • •

e

t

c

•

e

• • • • •

• • 0 • •

• • • • • •

• • • • •

• •

a

• • • •

* • •

•

• • • • •

e

• • • • • • • •

o

• • • •

a

,

- LUBRICATION SYSTEM

• •

•

9

•

• • •

• • • •

• • •

•

• • • • • •

• •

• • • •

• •

•

a

ft

• •

•

• •

a a

j

a

•

e

a

•

a

• •

a

•

s

• •

e

• •

•

Out of Fuel - Check

Lean Fuel Mixture - Readjust Rich Fuel Mixture or Choke Stuck Engine Flooded Poor Qual ity Fuel Dirty Carburetor Dirty Air Cleaner Dirty Fuel Filter

Defective Fuel Pump

INTERNAL ENGINE

Wrong Valve Clearance

Broken Valve Spring '

Valve or Valve Seal Leaking Piston Rings Worn or Broken Wrong Bearing Clearance

COOLING SYSTEM (AIR COOLED)

Poor Air Circulation Dirty or Oily Cooling Fins

Blown Head Gasket

- COOLING'SYSTEM

Insufficient Coolant Faulty Thermostat Worn Water Pump or Pump Seal Water Passages Restricted Defective Gaskets Blown Head Gasket

Defective Oil Gauge Relief Valve Stuck Faulty Oil Pump Dirty Oil or Fi Iter

Oil Too Light or Diluted Oi 1 Level Low Oil Too Heavy Dirty Crankcase Breather Valve

THROTTLE AND GOVERNOR

Linkage Out of Adjustment Linkage Worn or Disconnected Governor Spring Sensitivity Too Great Linkage Binding

(WATER COOLED)

•

INSTALLATION

The type of installation can affect the . life of the engine, the cost of operation and the frequency of

necessary service. Plan the installation carefully to ensure the best performance.

Because of the great variety of uses, and the many variations of the engine, these installation instruc-

tions are typical or general in nature. Use the

installation recommendations given as a general guide.

MOUNTING

There are several acceptable methods of. mounting the engine. Among factors to be considered are: location, type of foundation or support, etc. The engine should be mounted on a level surface if possible. Maximum operation angle is 15 degrees sideways, 30 degrees front to rear tilt. If the engine is to operate at an angle, be sure to re-mark the oil level indicator to compensate for the tilt.

method of coupling the engine to the

load,

•

VENTILATION

The engine must be provided with asupply of fresh air for cooling and for combustion.

Pressure Cooled Engine: Position the air inlet open-

ing directly in front of the engine and as close to the engine blower wheel as possible. The area ofthe inlet should be not less than 80 square inches. If louvers or.

grill work ere used, increase the area to compensate forthe reduced airflow. Provideextra ventilation ifthe driven load generates heat during operation.

The heated air outlet must allow the heated air to escape freely and prevent recirculation with the

cooling air. A duct between the compartment air inlet and the engine blower housing may be necessary.

Locate the air outlet opposite the intake or at least at a 90 degree angle. The area of the outlet should be at

least 15 percent larger than that of the inlet. Allow

sufficient room on all sides to permit access for servicing.

Open Air Installation: For installations where the

engine is operated outside, ventilation will be no

problem..However, in protecting the engine from the elements, see that nothing obstructs the flow of air around the engine.

AIR

OUT

FIGURE 1. AIRFLOW THROUGH VACU-

Vacu-F!o Cooled Engine: The vacu-flo equipped engine uses an integral flywheel-centrifugal fan to pull cool air into the engine shroud and over the cooling fins and surfaces of the engine, Figure 1. The heated air is directed through an air tight scroll which encases the flyvyheel fan. The scroll may be positioned to discharge heated air in the downward, upward, left or right direction. This is possible because the back section of the scroll (Figure 2) has four identical holes shaped to fit over the<end of the starter motor. The scroll outlet has a mesh-type screen for safety.

overheating can cause troubles ranging from vapor lock to scored

pistons and cylinders.

FLO SYSTEM

The outlet of the vacu-flo scroll must not be restricted or overheating will result. Engine

SCROLL BAC

SCROLL

If theduct length exceeds 5feet, increaseductsize30

percent. Use no more than two 90 degree radius-type

(not square-type) elbows if it is necessary to change air flow direction. When a duct is used between the scroll discharge and the outlet vent, its unobstructed airflow area must be at least as large as the scroll discharge. The cross-sectional area of theduct must be increased if air flow is restricted by bends, long runs,

screens or the exhaust pipe. Exhaust pipes running inside Vacu-Flo ducts should be covered with asbestos tape.

WARNING \ The safety screen used to covervents must be

••irii™««—I flow, and must be commensurate with safety standards for hazardous moving parts to avoid personal contact. Provide a short canvas section between the engine air outlet and the external duct or opening, to absorb vibration. If operation in cold weather is likely, installing a shutter in the airoutlet is advisable. Cold weather can cause overcooling if air flow is not regulated.

1/4-inch

mesh orlargertopermitsufficientair

EXHAUST

^ARNJINGJ Exhaust gases are toxic. Provide an adequate

gases. Check exhaust system regularly for leaks. Ensure that exhaust manifolds are secure and not warped. Be sure the unit is well ventilated.

exhaust system to properly expel exhaust

FIGURE 2.

VACU-FLO SCROLL POSITIONS

Should a vacu-flo engine chronically overheat, the

most likely sources of the problem are:

1.

Air inlet is obstructed or too small to allow proper

ventilation.

2.

Air discharge opening is partially blocked by

external ducts or exhaust systems.

3. Recirculation of heated air into fresh air inlet.

The vacu-flo installation permits greater freedom in choice of locating the air inlet and outlet openings, and permits the use of a compartment only slightly

larger than the engine itself.

60

The area of the air inlet must be at least/TWsquare inches. If a filter, grille, or louvers are useflTthe inlet opening must be increased accordingly. The air outlet opening should be located as close to the engine as possible.

Use a length of flexible tubing between the engine exhaust outlet and any rigid piping to absorb engine vibration.

Shield the line if it passes through a combustible wall or partition. If turns are necessary, use sweeping type (long radius) elbows. Increase one pipe size (from manifold outlet size) for each additional ten feet in length. Locate the outlet away from the air intake.

CARBURETOR

AIR INTAKE

Proper engine efficiency depends upon a supply of

fresh air to the carburetor. Under special conditions,

it may be necessary to move the air cleaner off the

engine, using a longerconnection hose as necessary.

For extremely dusty or dirty conditions, install a

special heavy duty air cleaner.

FUEL

SYSTEM

The engine uses either a diaphragm or pulsating diaphragm type fuel pump. The fuel pump has a 1/8-

inch pipe threaded inlet, fitted with a

1/4-inch

inverted flare tube fitting. If a solid wall line is used, form a loop in the line, or install a section of flexible fuel hose, to absorb vibration. If a line with a pipe thread end is used,

remove the flare type fitting from the fuel pump

inlet.

The fuel supply tank may be installed in any safe, convenient location. If the tank is installed within the engine enclosure, provide a vent line to the outside of the enclosure.

The installation of a fuel filter between the fuel tank

Snd the fuel pump is'recommended. The fuel filter should be fitted with a shutoff valve and should be easily accessible for cleaning.

4.

If the installation permits, belts should run

horizontally.

5. Some method'of disconnecting the load for starting is recommended. If a clutch is not used, a belt-tightener idler arrangement can be used.

Flexible Coupling:^lf a flexible coupling engine-to-

load drive is used, the load shaft must be in line and

centered with-the engine shaft (Figure 4).

CONNECTING

TO THE

LOAD

The dimensions of various power takeoff shafts are as

follows:

SHAFT

STD Rockford Clutch Gear Reduction

DIAMETER

1-7/16 1-7/16 1-1/4

LENGTH

3-1/16

3.-1/16 2-3/4-

KEY SIZE

3/8 3/8

1/4

Belt Drive: V-belts are preferable to flat belts. Consult a reliable belting supplier for recommendations regarding size of pulleys, number of belts, etc.

required.

A typical belt drive installation is shown in

Figure 3.

KEEP SHAFTS OF ENGINE

AND LOAD PARALLEL.

ENGINE POWER

TAKE-OFF ^

SHAFT

FIGURE 4. FLEXIBLE COUPLING

FLEXIBLE

COUPLING

Reduction Gear Drive: Reduction gear drives are mounted at the factory (when ordered). The method of connecting the load is the same as when connecting directly to the engine shaft.

KEEP PULLEYS ALfGNEt

WITH EACH OTHER

BELT IN TIGHTENED

POSITION - PULLING

LOAD

ENGINE

PULLEY

BELT IN LOOSENED

POSITION - NOT PULLING LOAD-

FIGURE 3. DRIVE BELT INSTALLATION

IDLER PULLEY

LOAD

PULLEY

BRACKET TO KEEP BELT OFF ENGINE

PULLEY

Comply with the following installation requirements:

1.

The.shafts of the engine and the load must be

parallel with each other.

2.

The pulleys of the engine and the load must be in

alignment.

3. Mount.the engine pulleys as close to the engine as possible.

Clutch Installation: A Rockford Clutch can be installed at the factory or in the

field.

Install the clutch

according to the following instructions and Figure 5.

KEYWAY

DRILL 13/64" HOLE'

CRANKSHAFT STUB SHAFT

A867

FIGURE 5. CLUTCH INSTALLATION

1/8" DEEP

CLUTCH CLUTCH

ASSEMBLY HOUSjNG

SET SCREW

I 1/32"

POWER

TAKE-OFF

SHAFT

Provide room for the clutch adapter casting by plugging the wet holes with a 3/8-16 x

1/2-inch

slotted headless set screw. Apply sealing compound to the threads and install screw flush with the cylinder block.

Drill a 13/64-inch hole (or filed slot) in the crankshaft

for.the clutch set screw. Locate center of hole 11/32-

inch from the end and directly opposite the keyway in

the crankshaft.

Install the clutch adapter, with drain slot downward, using two cap screws 3/8-16 x 2-inches on the lower and one cap screw 3/8-16 x 1 -3/4-inch on the upper #2 cylinder side (cylinder nearer clutch). Install the3/8x 3-7/8-inch stud through the adapter into the engine block upper remaining hole. Use a lock washer on each assembly screw. Use a flat washer and a lock washer under the stud nut.

Install the crankshaft key. Remove the clutch set

screw. Install the clutch assembly (less housing) to the crankshaft, driving iton carefully with asoft-faced hammer until set screw hole is aligned. Install set screw to bottom in crankshaft hole, then back it out one full

turn.

Tighten clutch retaining screws until clutch is clamped securely to crankshaft. Lock the screws and tighten the set screw.

Install the clutch housing sothattheclutch throw-out fork engages the throw-out collar. Be sure the serrated shaft is properly meshed with the clutchplate.

Use two cap screws 7/16-14 x 2-inches on the

lower and one cap screw 7/16-14 x

1-3/3-inch

on the upper #2 cylinder side. Install the stud washer and nut. Lubricate the two grease fittings just until grease appears.

BATTERY

CONNECTIONS

(Engines

with

Automotive Type Separate Starter)

Connect the 12 volt battery positive cable to the engine start switch terminal. Connect the battery

negative cable to the ground point on the engine oil

base (Figure 6).

BATTE

POSITIV

CABLE

Apply grease to splined power takeoff shaft.-Position the clutch throw-out to align the grease fitting with the hole in the housing

(#1

cylinder side, horizontal).

Pull the throw-out collar outward to remove tension.

(FASTEN UNDER CONVENIENT

CABLE

BOLT ON ENGINE)

FIGURE 6. BATTERY CONNECTIONS

IVE

10

BEFORE

Crankcase Oil: Be sure the crankcase has been filled with oil to the "FULL" mark on the oil level indicator.

Use oil with the API (American Petroleum Institute) designation SE or SE/CC. Do not use an oil with the designation CD unless it is also designated SE and the oil manufacturer certifies it will perform satisfactorily in gasoline engines.

Recommended Fuel: Use clean, regular grade,

automotive gasoline. Do not use highly leaded

premium types.

For new engines, the most satisfactory results are obtained by using nonleaded gasoline. For older engines that have previously used le'aded gasoline,

heads must be taken off and all lead deposits removed

from engine before switching to nonleaded gasoline.

gasoline, preignition could occur causing severe damage to the

engine.

WARNING

Open the fuel line valve (when used) and operate

primer to assure fuel supply after filling an empty

tank.

STARTING

If lead deposits are not removed from engine before switching from leaded to nonleaded

Never fill the tank when the engine is running. Leave some space in the tank for fuel expan

j

sion.

APPLYING

When applying the load to a new or reconditioned engine, it should be applied gradually in about four

steps;

each step of not less than 30 minutes running

time.

Start with 1/4

BATTERY

The battery charge rate is controlled by a charge

regulator. The regulator is set to allow the proper rate

of charge at operating speed.

STOPPING

Disconnect all load before stopping the engine. Engines equipped with battery ignition are stopped by positioning the ignition switch to the OFF position.

LOAD

load,

then 1/2, 3/4 and full

CHARGING

THE

ENGINE

HIGH TEMPERATURES -

1.

See that noth ing obstructs

:

engine.

2.

Keep cooling fins clean. Air housing should be

properly installed and undamaged.

ai r flow to and from the

load.

STARTING

1.

Move ignition switch to its ON position.

2.

Push START button to crank engine.

If the engine fails to start at first attempt, inhibitor oil used at the factory may have fouled the spark plugs. Remove the plugs, clean in suitable solvent, dry thoroughly and install. Heavy exhaust smoke when the engine is first started is normal and is caused by inhibitor oil.

STARTING

1.

Hold choke about three quarter way closed or as

necessary according to temperature conditions.

2.

Pull start rope with a fast steady pull to crank

engine. Do not jerk.

3. Open choke as engine warms up.

(Electric

(Manual

Start)

LOW

TEMPERATURES

1.

Use correct SAE No. oil for temperature

ditions. Change oil only when engine is warm.

2.

Use fresh

sation.

3. Keep fuel system clean and batteries in a well charged condition.

4.

Partially restrict cool air flow, but use care to

avoid overheating.

DUST

1.

Keep unit clean. Keep cooling system clean.

2.

Service air cleaner as frequently as required.

3. Change crankcase oil and filter more often than recommended under normal conditions.

4.

Keep oil and gasoline in dust tight containers.

5. Keep governor linkage clean.

fuel.

Protect against moisture conden-

AND DIRT

11

con-

HIGH

ALTITUDE

For operation at altitudes of 2500 feet or more, close the carburetor main jet adjustment slightly to maintain proper air-to-fuel ratio. Referto the Fuel System section.

Maximum power will be reduced about 4

percent for each 1000 feet increase in altitude.

PROTECTION SERVICE

PERIOD

FOR

EXTENDED

OUT-OF-

Protect an engine that is to beout-of-service for more

than 30 days as follows:

1.

Run engine until thoroughly warmed up.

2.

Turn off fuel supply and run until engine stops

from lack of

fuel.

3. Drain oil from oil base while still warm. Attach a warning tag to refill before operation.

4.

Remove each spark plug. Pour one ounce (two

tablespoons) of rust inhibitor (orSAE#50) oil into

cylinder. Crank engine over a few times to distribute oil film on cylinder walls and rings.

Reinstall each spark plug.

5. Service air cleaner per maintenance schedule.

6. Lubricate governor linkage. Protect against dust, etc. by wrapping with a clean cloth.

7. Plug exhaust outlet to prevent entrance of bugs,

moisture, or dirt.

8. Wipe entire unit clean. Coat parts likely to rust with a light film of grease or oil.

9. Provide a suitable cover for entire unit.

10.

Disconnect battery and follow standard battery

storage procedure.

CAUTION ) Discharged batteries are subject to severe

damage if exposed to freezing temperatures. Store all batteries in a fully charged condition and maintain charge during storage.

RETURNING

1.

CHECK SERVICE IDENTIFICATION TAGS to

THE SET TO

OPERATION

properly service the engine.

2.

Uncover and remove all storage seals from

engine. Remove any dust, dirt, or foreign matter.

3. CHECK fuel supply tanks for moisture accumulations (drain tanks if necessary). CHECK lubricating oil for moisture or contamination (drain if necessary). CHECK fuel line connections,

all wiring connections, and exhaust line

connections.

4.

Service air cleaner. Bleed fuel system (if moisture

or contamination are found in

fuel,

replace filters

and clean fuel pump sediment bowl).

5. Check tag on oil base and verify that oil viscosity is still correct for existing ambient temperature.

6. Clean and check battery. Measure specific gravity (1.260 at 25° C [77° F]) and verify level to be at

split

ring.

If specific gravity is low, charge until correct value is obtained. If level is low, add distilled water and charge until specific gravity is correct.DO NOT OVERCHARGE..

"WARNING k

batteries in operation. Ignition of these gases can cause severe personal injury.

Do smoke

Explosive gases are emitted from

while servicing batteries.

7. Check engine forfuel oroil leaks. Correct leakage as required.

8. Install fully charged batteries.

9. Start engine and check while running for leaks, correct voltage output, and proper cooling.

After engine has started, excessive blue smoke will be exhausted

and the engine will run rough until the rust inhibitor or oil has burned away.

12

PERIODIC

MAINTENANCE

TABLE

SERVICE THESE ITEMS

1.

PERIODIC

MAINTENANCE

* Inspect Engine Generally

" Check Fuel Supply

Check Oil Level Clean Governor Linkage Change Crankcase Oil Check Breaker Points Check Battery Electrolyte Level Clean Fuel Filter Check Spark Plugs Replace Oil Filter Replace Air Cleaner Remove Deposits.in.Combustion Chamber Check Valve Clearance Inspect Valves, Grind if Necessary Complete Reconditioning

* - Check for exhaust leaks, fuel leaks, proper mounting, etc. X* - Perform more often under dusty or extreme cold weather conditions. X-1 - Recommended interval in hot weather or heavily loaded conditions.

SCHEDULE

AFTER EACH CYCLE OF INDICATED HOURS

8

X X X

50

X*

100

xl X*

200 500

X X X X

X* X*

1000

X

xl •• X

. X

5000

X

PERIODIC MAINTENANCE SCHEDULE

Regularly scheduled maintenance is the key to lower operating costs and longer service life for the unit. The schedule (Table-1) can be used as a guide. However, actual operating conditions under which a unit is run should be the determining factor in establishing a maintenance schedule. When operating in very dusty or dirty conditions, some of' the service periods may.have to be reduced. Check the condition of the crankcase oil, the filters, etc. frequently until the proper service time periods can be established. When any abnormalities occur in operation—unusual noises from engine or accessories, loss of power, overheating, etc.— contact your Onan dealer.

CRANKCASE

The oil capacity is,3-1/2 U.S. quarts (4 with filter). Fill to the "FULL" mark on theoil level indicator, Figure?..

OIL

13

CAP AND OIL

LEVEL INDICATOR

KEEP OIL

AT THIS LEVEL. NEVER OPERATE

ENGINE WITH OIL

BELOW THIS LEVEL.

FIGURE 7: OIL LEVEL INDICATOR

A874

-FULL

ALWAYS REPLACE CAP TIGHTLY. OR

OIL LEAKAGE MAY

OCCUR.

When adding same brand

oil

and

Various brands

mixed together.

between changes, always

weight that

of oil

may

is in the

not be

compatible when

use

the

crankcase.

Oil consumption than with a single grade

parable viscosities

oils

are

generally more desirable, unless anticipating a wide range oil

for

the

expected conditions.

TEMPERATURE

• Below 30°

Above

Check

oil

may be

higher with a multigrade

oil if

at

210° F. Therefore, single grade

of

temperatures.

0°

to 30°

to 90°

90°

level daily. Change

both' oils have com-

Use the

proper grade

GRADE

5W

10W 30 50

oil

every

100

hours

oil

under normal operating conditions. When operating in extremely dusty

or

dirty conditions, change

oil

more often.

OIL FILTER

RIP

PAN

FIGURE

8. OIL

FILTER LOCATION

CRANKCASE BREATHER

The engine isequipped with a ball check valve (Figure

9)

for maintenance crankcase become pressurized, leaks indicator, clean baffle

Clean baffle material doesn't come apart

maintaining crankcase vacuum.

is

generally required. Should

as

evidenced

at the

or

seals

or

around

in

replace crankcase breather baffle periodically.

the

cap

of

suitable solvent.

and

work into

the

oil

the

manifold.

BREATHER

No

the

by oil

level

Be

sure

HOSE

OIL FILTER

Change Remove terclockwise, using a filter wrench. provided with indicated. located below with a film finger-tight plus that seen,

period.

the

markings

change

crankcase

filter (Figure the

filter

It is

advisable

the

filter. Coat rubber gasket

of oil

before installing. Install

1/4 to

on the oil

the

filter and shorten

oil

filter every

8) by

to

1/2

prevent

to

turn.

air

wipe

dry the

If

oil becomes so dirty

level indicator cannot

the

200

hours.

.turning coun-

Add the loss

in

the

drip

on

the

strip

area pan filter filter

be

filter service

14

CAP

ANO

BREATHER TUBE

FIGURE

HOSE

CLAM

VALVE

9!

CRANKCASE BREATHER

AIR

CLEANER

The NHC engine uses a replaceable, spin-on air

cleaner/ Figure 10. Remove and replace every 200

hours.

CAUTION

cause severe damage to engine parts.

Do not run engine with air cleaner removed. Intake of dirty air or solid materials could

AIR

CLEANER

REDUCTION

GEAR

DRIVE

Drain the gear box after the first 100 hours of operation and refill with fresh lubricant of the

recommended grade. Repeat this procedure every six months thereafter, or every 100 hours.

Use only SAE 50 motor oil orSAE 90 mineral gearoil. Do not use lubricants commonly known as extreme pressure lubricants, hypoid lubricants, etc.

Maintain the proper oil level between changes. Overfilling will cause foaming, which can lead to an oil leak due to overheating. Remove the filler plug on top of the case and theoil level plug from the face of the gear

case.

Fill the case until the oil just begins to flow from the oil level plug hole. Gear box holds 1/2 pint U.S. measure. Replace both plugs. See Figure 12.

VENT PLUG

FIGURE 10. AIR CLEANER

GOVERNOR

LINKAGE

The linkage must be able to move freely through its entire travel. Every 50.hours of operation clean the metal joints as shown in Figure 11. Also inspect the

linkage for binding, excessive slack and wear.

Clean and lubricate metal ball joints. Don't lubricate plastic joint^

KEEP

GOVERNOR

LINKAGE

LUBRICATED

FILL WITH OIL TO LEVEL OF HOLE

FIGURE 12. REDUCTION GEAR DRIVE

EXHAUST

SYSTEM

Make regular inspections of the exhaust system throughout the entire life of the engine. Locate leaks

in muffler and piping while the engine is operating. Repair all leaks immediately after they are detected

for personnel safety.

WARNING

hazard in enclosed areas.

Leaky exhaust systems emit noxious carbon

monoxide fumes which are a potential safety

FIGURE 11. GOVERNOR LINKAGE

BATTERY

Check charge condition. Check electrolyte distilled water to keep electrolyte at its proper level .-In freezing weather, run engine immediately after adding water. Keep battery.connections tight and clean. ..

level.

15

Add

FUEL

SYSTEM

GASOLINE

CARBURETOR

For correction of problems traced to,the, gasoline carburetor, use the appropriate procedures selected

from the following sequence, referring to Figures 13

and 14. Adjustment Under Load: Adjust the carburetor as

follows when a full load can be applied.

1.

Make sure the ignition system is working properly

and that the governor is adjusted.

2.

Start the engine and allow it to warm up. If the

carburetor is so far out of adjustment that the engine will not start, close both needle valves gently to their seats. Then open each 1 to 1-1/2 turns,

first the idle and then the main adjustment.

3. With no load applied to engine, turn the idle adjustment out until the engine speed drops slightly below normal. Then turn the needle in

until the engine speed returns to normal.

4.

Apply a full load to the engine and then carefully

turn the main adjustment in until the speed drops slightly below normal. Turn the needle out until the engine speed retums to normal.

Adjustment Under "No Load" Conditions: When a

THROTTLE

STOP SCREW

ADJUSTMENT

FIGURE 14. CARBURETOR ADJUSTMENTS

FUEL IDLE

ADJUSTMENT

A

FLOAT BOWL NUT

MAIN FUEL

B

load cannot be applied, adjust the carburetor as follows: .

1. Perform steps 1 and 2 as given under Adjustment Under Load.

2.

Pull out on the governor mechanism to slow the

unit down to about 800 to 900 rpm.

ADJUSTMENT NEEDLE-

IDLE

CHOKE SHAFT

CHOKE PLATE

FLOAT

ASSEMBLY

FUEL BOWL

THROTTLE PLATE

THROTTLE SHAFT

AND LEVER

-MAIN JET

ADJUSTMENT

FLOAT AXLE

POSITION OF SPRING

AFTER INSTALLATION

^ SPRING

POSITION HOOK

UNDER TANG ON

FLOAT

EH

FIGURE 13. CARBURETOR ASSEMBLY

16

3. Set the idle adjustment screw for even operation (so the engine is firing on both cylinders and is running smoothly).

4.

Release the governor mechanism to allow the

engine to accelerate. If the engine accelerates evenly and without a lag, the main adjustment is correct. If not, adjust the needle outward about

1/4 turn and again slow down the engine and release the mechanism. Continue until the engine

accelerates evenly and without a time lag after

releasing the governor.

5. With the carburetor and governor adjusted, set the throttle stop screw at the desired idle speed.

Float-Level Check: If the carburetor adjustment fails

to provide satisfactory operation, remove the car-

buretor and check the float level as follows:

1.

Remove the fuel line; air cleaner hose, governor

linkage and choke wires.

2.

Remove the two carburetor mounting nuts and

remove the carburetor.

3. Unscrew the float bowl nut and remove the entire

main fuel adjustment assembly from the float bowl.

4.

Invert the carburetor and check that the float

surface nearest the gasket is 1/8 +

1/16-inch

from the gasket. Bend the float tab as required to produce this spacing.

If the carburetor utilizes an internally spring loaded fuel inlet valve;

the float surface should be 1/8 ± gasket with the full weight of the float compressing the spring in the needle.

1/16-inch

from the

5. Reassemble, install and test.

6. See Figure 15.

BEND TAB

TO ADJUST

GASKET TO FLOAT

DIMENSION 1/8 INCH

A9I3-I

FIGURE 15. FLOAT LEVEL ADJUSTMENT

Carburetor Removal and Disassembly: Remove and

disassemble the carburetor assembly as follows,

referring to Figure 15:

1.

Remove the fuel line, air cleaner hose, governor

linkage, and choke wires.

2.

Remove the two carburetor mounting nuts and ' remove the carburetor.

3. Remove the main .jet assembly and bowl. '

4.

Remove the float pin and float.

5. Lift out the fuel inlet valve and unscrew the valve seat.

6. Remove the idle adjustment needle.

7. Remove the throttle plate screws and the plate, ' then pull.out ttie throttle shaft. ,

8. Remove the choke plate screws and plate, then pull out the choke shaft.

Carburetor Assembly and Installation: Clean the components and repair or replace defective or worn parts.

Use acetone or alcohol to dissolve gum deposits if carburetor cleaner is not effective. Soak the parts in carburetor cleaner, using it asdirected by the manufacturer. Clean all carbon from the car-

buretor bowl, especially in the area of the throttle plate.

Blow out clogged passages with compressed air. Check the needles, nozzle, and float for damage

or fuel loading. Check the choke and throttle shafts. Reassemble and install as follows:

1.

Install the throttle shaft and plate, using new

screws and lock washers. Install with bevel mated to the carburetor body. If the plate is marked with the letter C, install it with the mark on the side toward the idle port when viewed from the flange

end of thecarburetor. To centerthe plate, backoff the top screw, close the throttle leverand then set the plate by tapping it with a small screwdriver.

2.

Install the choke shaft and plate. Centerthe plate

in the same manner as the throttle plate (see step

1).

Use new screws and lock washers.

3. Install the fuel inlet valve seat and valve.

4.

Install the float and floatpin, adjusting thefloat.as

previously described.

5. Install the bowl ring gasket, bowl and bowl nut. Make sure that the bowl is centered in the gasket and tighten the main jet assembly securely. Turn in until it seats and back out to 1-1/2 turns.

6. Install the idle adjusting screw finger-tight. Then back it out 1 to 1-1/2 turns.

7. Install thechokeand adjustas previously described.

8. Install the carburetor on the engine and connect the gasoline inlet,, governor mechanism, air cleaner hose, and choke wires.

9. Adjust the carburetor needle settings as described under Adjustments and check out the performance.

Complete Replacement: Complete replacement of the carburetor should be performed as follows:

1.

Follow the previously given disassembly instruc-

tions as required-for removal of the defective carburetor.

2.

Replace the carburetor vyith a new unit, using

- attaching parts in good condition and making all the connections previously disengaged.

3. Adjust the needle settings as described under Adjustments.

17

DIAPHRAGM

FUEL

PUMP

Some engines use a diaphragm-type fuel pump,

Figure 16. If fuel does not reach thecarburetor, check

the fuel pump before dismantling it.

1.

Disconnect the fuel line at the carburetor.

2.

' Crank' the engine and observe whether fuel

comes from the line at the carburetor.

WARNING

ignition wires.

Be sure to direct the fuel flow into a container so gasoline does not spill on

3. If there is enough fuel in the tank, and line does not have fuel flowing, the pump needs replacing.

Pump failure is usually caused by a leaking diaphragm, valve or valve gasket, a weak or broken spring or wear in the drive linkage. Gasoline diluted oil may also indicate a faulty pump.

Always return the hand priming lever all the way inward so that lever does not prevent normal operation of fuel pump.

UPPER PUMP BODY (NOT SERVICEABLE)

•VALVE 0> GASKET -0>|!

2.

Make an indicating mark with a file across a point

at the union of the fuel pump bolt and cover. Remove the assembly screws and the upper pump body.

3. Turn the pump body over and remove the valve plate screw and washer. Remove the valve retainer, valves, valve springs, and valve gasket, noting their position. Discard the valve springs,

valves and valve retainer gasket.

4.

Clean the pump body thoroughly with a solvent

and a fine wire brush.

5. Holding the pump cover with the diaphragm surface up, place the new valve gasket in the cavity. Assemble the valves in the cavity. Reassemble valve retainer. Lock in position by inserting and tightening the fuel pump retainer

screw.

6. Place the pump body assembly in a clean work area and rebuild the lower diaphragm section.

7. Holding the mounting bracket, press down onthe diaphragm to compress the spring under it, then

turn the bracket 90 degrees to unhook the diaphragm so it can be removed.

8. Clean the mounting bracket with a solvent and a fine wire brush.

9. Replace the diaphragm operating spring, stand

the new spring in the casting, and position the diaphragm. Press down on the diaphragm to compress the spring and turn it 90 degrees. This will reconnect the diaphragm.

10.

Hold the bracket, place the pump cover on it (making sure the indicating file marks are in line)

and insert the four attaching screws but do not tighten.

With the hand on the mounting bracket only, push the pump lever to the limit of its travel and hold in this position while then tightening the four screws. This is important to prevent stretching the diaphragm.

11.

Mount the fuel pump on the engine, using new

mounting gaskets. Connect the fuel lines.

"LOWER SIDE

DIAPHRAGM GASKET"

LOWER

BODY

•PARTS INCLUDED IN REPAIR KIT

FIGURE 16. DIAPHRAGM FUEL PUMP

Fuel Pump Reconditioning: Reconditioning of the fuel pump should be as follows, referring to Figure 16.

1.

Remove the fuel lines and mounting screws

holding the pump to the engine.

PULSATING

DIAPHRAGM

FUEL

PUMP

Pulsating diaphragm fuel pumps (Figure 17) use a combination of crankcase and spring pressure to work a diaphragm thus pumping

fuel.

This pump may be mounted on the engine rear housing on NHCV models and on the upper right hand corner of the blower housing on NHC models. See Figure 17.

On the downstroke of the engine piston, when the crankcase pressure is greatest, the pump diaphragm is forced back against the diaphragm spring compressing it and drawing fuel into the pump intake

chamber. The fuel then passes through the intake

reed valve into the output chamber side of the pump.

On the compression stroke, when crankcase pressure

is the lowest, the diaphragm spring forces the

18

PUMP COVER GASKET

,r

«l!'

ro,'

PULSATING

SCRIBE

LINE

DIAPHRAGM

FUEL

PUMP

(EXPLODED

VIEW)

PUMP MOUNTS ON

NHC BLOWER HOUSING '

FIGURE

17.

PULSATING

DIAPHRAGM

13

FUEL

PUMP MOUNTS ON NHCV ENGINE REAR HOUSING

PUMP

diaphragm

reed valve into

out

pushing fuel through the pump output

the

output chamber and into

the

fuel

line.

Servicing

1.

Remove vacuum

2.

Scribe

the

Pulsating Diaphragm Fuel Pump

wearrcracking,

two

lines

and

etc.

(one

fuel lines. Inspect lines

each

on

opposite ends

for

pump) across pump parts. This will insure correct alignment carburetor when pump

of

pump parts with each other

is

reassembled.

and

3. Remove fuel pump attaching screws.

4.

Holding pump carefully, pull sectionsof thepump

apart. The diaphragm, plunger, return spring plate,

pump body and gaskets will

5. Check parts

for

wear and damage. Replace with

now be

and

loose.

new parts where necessary.

6.

The

pump

air

unclogged

bleed hole

to

allow unrestricted movement

in

pump base must

pump diaphragm.

CAUTION

while inhibiting pump operation.

DN

A clogged diaphragm air bleed hole can

i

cause diaphragm wear and seal damage

7. Replace gaskets and reassemble pump as shown in Figure

17.

8. Install pump and replace lines. Makesure fuel line

clamps

T WARNING I Use care when reassembling the pump. '

•••'•fl All parts must be perfectly aligned or the pump will leak creating a fire hazard.

are

replaced

on

fuel line.

of

be of

THERMO-MAGNETIC

CHOKE

(Optional)

This choke uses a strip heating element and a heat sensitive bimetal spring position.

In

addition

during engine cranking, closing

to

control

to

this, a solenoid

the

choke plate

is

choke

all or

actuated

part way, depending on ambient temperature. The bimetal is factory opening under

Choke Adjustment: needed, not attempt adjustments until engine down

set to

it

must

for at

any

least

position

the

ambient condition.

If

adjustment

be

made

at

ambient temperature.

one

hour. Loosen

choke

of the

the

to the

proper

bimetal

has

been shut

screw which

is

Do

secures the choke body assembly. Refer to Figure 18.

LOOSEN THIS

SCREW

AND

THE

ASSEMBLY

FIGURE

ROTATE

ENTIRE COVER

18.

THERMO-MAGNETIC CHOKE

(17/64

WASHER, INSULAT

RING,RETAINING

PLATE,

CHOKE COVER

WASHER

I.D.X5/8

SPRING,CHOKE

LEVER,LIMIT

O.D.X1/16")

FIGURE

19.

—,

-,

/ ^-ARMATURE ASSY.

COIL,SOLENOID

FRAME,SOLENOID

(Rv WASHER,SHAKEPROOF

WASHER (24/64

LEAD,GROUND

CHOKE ASSEMBLY

I.D.X9/16

PLATE,

BODY,CHOKE

CHOKE

MOUNTING

O.D.X1/16")

20

Rotating tne choke body clockwise richens and counterclockwise leans the, choking 'effect. For ambient temperatures above 85° F. the choke should be fully opened. For ambient temperatures below 25° F, the choke should be opened i/4 inch with the solenoid not engaged. Tighten the screw-that secures

.the choke-body. ...

If the choke will not close, check for binding,

•incorrect adjustment, or incorrect assembly of the bimetal and ;heater .assembly." IMhe choke will not open after the engine starts, check choke bimetal should be warm to the touch within a minute or two after starting.

To disassemble the choke, refer to Figure"!9.

Ifthe heater assembly will not heat properly, check for broken heater wire, high resistance connections or broken lead wires to the bimetal and heater assembly. With the element at room temperature, check the

.-for

heating. The

heater resistance with an ohmmeter. The resistance should be about 37.8 to 46.2 ohms;for a 12 volt system.

If the heater is defective, replace. There must-be slack

in the lead wires between the choke.body and the

. bimetal and heater assembly. When the start button is

engaged,' ed lever to contact the solenoid core. If this does not occur, check for broken lead wires or a defective solenoid core.

The solenoid coil should have a-resistance of 2.09-to-

2.31 ohms in a 12 volt system. Assembly: Refer to Figure 19. When assembling the

thermomagnetic choke, connect the bimetal and

heater assembly as follows:

1.

Lead tagged G to ground terminal in coil

. "2: Lead tagged H to either of the HI terminals on the

the solenoid should cause the spring

solenoid. soleribi,d..core.

load-

'

'n

21

GOVERNOR

SYSTEM

GOVERNOR

Where engine speed

governor engine speed another speed ordered).

most important factors

speed desired from

Before making governor adjustment, about

temperature.

It

is governor spring has become fatigued. If, after properly making erratic, install

A tachometer for accurate governor adjustment.

Check

lever points. A binding condition

governor

Excessive looseness will cause a hunting condition and regulation will forth several times either

and adjust

is set at the

15

difficult

the

for

of

these conditions exist, determine

ADJUSTMENT

is

governor controlled,

factory

of

2400 rpm

is

Proper governor adjustment

minutes

to

determine

all

other adjustments,

a new

for

checking engine speed

governor arm, linkage, throttle shaft

binding to act

or

slowly

be

replace parts

at

specified when

in

the

engine.

to

reach normal operating

spring (Figure

excessive wear

and

erratic. Work

by

hand while

to

allow a nominal

no load operation (unless

the

engine

is one of the

maintaining

if,

after long usage,

at any

regulation will

as

needed.

the

power

run the

the

regulation

20 and 21).

is

at

connecting

pointwill cause the

be

the

arm back

the

engine idles.

the

is

and

engine

the

is

still

required

and

poor.

and

If

cause

Procedure:

1.

Adjust

2.

Adjust

3. Adjust

4.

Check

5. Adjust

6. Check

7. Recheck

8.

Set the

Linkage: length the throttle housing. stopped and tension on

the carburetor stop boss. This setting allows immediate control chronizes travel shaft.

Speed Adjustment: operates

governor spring. Increasing spring tension increases

the

carburetor main

mixture

connected.

binding

engine speed

operation needed.

at

full load operation.

the

carburetor idle needle with

the

length

the

governor linkage and throttle shaft

or

excessive looseness.

the

governor spring tension

the

rpm drop between

and

the

carburetor throttje stop screw.

The

engine starts

of the

carburetor throttle lever

linkage connecting the governor arm

arm is

Adjust

by the

is

determined

of

.the governor linkage.

at no

speed adjustment.

the

governor after starting

of the

load operation.

adjust

adjusted

length

on

the governor spring, the stop

governor arm

The

by the

jet for the

no

load and full load

the

governor sensitivity

at

wide open throttle.

by

rotating

so

that with is

1/32-inch

and the

speed

at

which

tension applied

for

the

and

the

best fuel

no

load

for

nominal

as

The

to

ball joint

engine

from

the

syn-

throttle

engine

to the

THIS

DISTANCE DETERMINES SENSITIVITY

CARBURETOR

THROTTLE

PLATE-

ADJUSTING STUD

•GOVERNOR ADJUSTMENT

ARM-

BALL JOINT

GOVERNOR

ARM

SPRING

FIGURE

20.

GOVERNOR ADJUSTMENTS

22

DECREASE SPEED

INCREASE SPEED

GOVERNOR ARM

EXTENSION

GOVERNOR LINKAGE

MAXIMUM SPEED STOP

FIGURE

21.

VARIABLE

engine speed. Decreasing spring tension decreases engine speed. The no load speed of the engine should be slightly higher than the speed requirements of.theconnected

load.

For example: If the connected load is to turn at 3510 rpm, set the no load speed of the engine at about 3600 rpm. Check speed with a tachometer.

If a speed adjustment is needed, turn the speed adjusting nut in to increase the speed or out to decrease the speed (Figure 21).

Sensitivity Adjustment: The engine speed drop from no load to full load should be not less than 100 rpm. Check the engine speed with no load connected and again after connecting full

rpm at no

load.

"

load.

Do not exceed 4000

The sensitivity of the governor depends upon the

position of the arm end of the governor spring. A series of. holes in the governor arm. provides for adjustment. To increase sensitivity, move the spring toward the governor shaft. To decrease sensitivity, move the spring toward the linkage end of the governor arm.

If the setting is too sensitive, a hunting condition (alternate increase and decrease in engine speed) will result. If the setting is not sensitive enough; the speed

variation between no-load and full load conditions will

.be too great. Therefore, the correct sensitivity will

result in the most stable speed regulation without causing a surge condition.

Always recheck the speed adjustment after a

sensitivity adjustment. Increasing sensitivity will cause a slight decrease in speed and will require a slight

increase in the governor spring tension.

Variable Speed Governor Adjustments: These engines are adapted for use where a wide range of speed settings is desired. The design of the variable speed governors give an automatic increase in sensitivity when the speed is increased and the result

is good stability at all speeds.

To adjust the variable speed governors, refer to

DECREASE SPEED

MINIMUM SPEED STOP

SPEED

GOVERNORS

Figure 21 and the following:

1.

Run the engine and make necessary carburetor

adjustments.

2.

Adjust the throttle stop screw on thecarburetor to

allow a recommended minimum idling speed of 900 rpm. A lower minimum does not assure smooth operation under

load.

3. Adjust the tension of the governor spring for minimum speed.

, For governors having a manual control arm, set lever to

minimum speed with no load and adjust the spring tension for ahout 1500 rpm.

For governors having a Bowdin wire remote control knob . (NHC engines with mounted.engine controls), pull back the knob and slide to the first notch (low.speed). Adjust speed to about'1500 rpm (or the desired low speed) at no load by turning the knob as required.

4.

Adjust the sensitivity/while operating at minimum

speed to attain the smoothest no load tb full load operation as follows:

To decrease sensitivity (allow more speed drop from no load to full load operation) move the governor spring outward into a different groove

. or-hole in.the extension arm.

To increase sensitivity (closer regulation by the

governor which permits less speed drop from no.

•load to full load operation)-, move the governor

• spring inward into adifferentgrooveorhole in the extension arm.

. 5, Apply a full load and shift the variable control to.

maximum.speed—moving the control arm to the

. - -righf or shifting the control knob and slide to the

., second notch. For the governor control with the

control arm, set the screw in the bracket slot to stop lever travel at the desired maximum full load speed position. For the control with the control

knob and slide, increase or decrease speed by

turning the knob as required.

Approximately 3000 rpm is the recommended max-

imum full load.speed for continuous operation. The-

speed must agree with the load requirements... -

23

«NmC!tN

SYSTEM

BREAKER

To maintain maximum efficiency from the engine, change the breaker points every. 200 hours of operation.

Proceed as follows:

1.

Remove the two screws and the cover on the

breaker box.

2.

Remove the two spark plugs so engine can be

easily rotated by hand. If plugs have not been

changed within the last 100 hours, replace them with new ones after setting the breaker points.

3. Refer to Figure 22. Remove mounting screw (A) and pull the points out of the box just far enough so screw (B) can be removed and leads disconnected.

4.

Remove screw (C) and replace condenser with a

new one.

5. Replace points with a new set but do not completely tighten mounting screw (A).

6. Rotate the engine by hand until the 20° BTC mark

on gear cover aligns with mark on flywheel. Turn another 1/4 turn (90°) to ensure points are fully open.

7. Using a screwdriver inserted in notch (D) on the right side of points, turn points until gap measures .016-inch with a flat thickness gauge. Tighten mounting screw and recheck gap.

8. Check ignition timing.

POINTS

simultaneously, thus the need for a distributor is eliminated/ top center), and should be maintained forbestengine performance. Always check timing after replacing ignition points or if noticing poor engine perfor-

mance. Proceed as follows:

Timing Procedure—Engine Running:

1.

To accurately check the ignition timing, use a

timing light with engine running at idle speed.

Connect the timing light according to its manufacturer's instructions. Either spark plug can be used as they fire simultaneously.

2.

Start the engine and check the timing. The pointer

on the flywheel should line up with the 20° mark on the cover. The timing hole through the flywheel and the timing marks on the timing gear cover can be seen by looking through the flywheel blower screen. See Figure 23.

If timing marks do not line up, readjust point gap. To advance timing, slightly close gap on breaker points. Recheck timing and breaker point gap after making this adjustment.

Timing Procedure—Engine Not Running: If a timing light is not available, check the timing as follows:

1.

Connect a continuity test lamp set across the

ignition breaker points. Touch one test prod to the breaker box terminal to which the coil lead is connected and touch the other test prod to a good ground on the engine.

2.

Tum crankshaft against rotation (coun-

terclockwise) until the points close. Then slowly turn the crankshaft with rotation (clockwise).

3. The lamp should go out just as the points break which is the time at which ignition occurs

(20° BTC).

Spark advance is set at 20° BTC (before

slightly open gap on breaker points. To retard timing,

1

MOUNTING SCREWS

FIGURE 22. BREAKER POINT ADJUSTMENT

TIMING

The timing on the engine is preset at the factory. A

non-movable breaker point box is used, however a slight timing change could be made by adjusting points.

The engine is equipped with an automotive type

battery ignition system. Both spark plugs fire

PRESSURE

RrREWS

COOLED

ll

ENGINE

POINTER ON TIMING

HOLE IN FLYWHEEL

24

FLYWHEEL

FIGURE 23. FLYWHEEL TIMING HOLE

TIMING

VACU-FLO

ENGINE

Engine timing is advanced or retarded by opening or closing the breaker point gap. Setting thepointgap at

0.016 inch is the most accurate method of timing the engine.

Dynamic timing (engine running) may be less accurate because the sight angle from the viewer to the flywheel scribe mark and timing pointer may vary ± 2° from 20° BTC, Figure 24.

The timing pointer is mounted on the cylinder block

above the oil filter; it is made accessible by removing

the right hand shroud.

IGNITION

COIL

To test primary and secondary windings within the

ignition coil proceed as follows:

•

1.

Use Simpson 260 VOM or equivalent.

2.

Place black lead on ground (-) terminal of coil and

red lead to positive (+) terminal. Primary resistance should read 4.30 (±10%) ohms @

70° F.

3. Change resistance setting on ohmmeter. Place ohmmeter leads inside of spark plug cable holes

(Figure 26). Secondary resistance should read 14,000 (+10%) ohms @ 70° F.

4.

If any of the above conditions are not met, replace

coil.

Refer to Parfs Catalog for correct part

number.

OIL FILTER

' BTC MARK

ON FLYWHEEL

FIGURE 24. VACU-FLO ENGINE—TIMING

MARK AND POINTER

SPARKPLUGS

Remove both spark plugs and install new ones every 100 hours. Use Onan spark plugs 167-0240 or equivalent. .Check to be sure spark plug gap is set at .025

inch,

Figure 25.

CAUTION

battery at all times when engine is running. Do not reverse battery cables.

BATTERY

This engine uses a 12 volt, negative ground

system.

Alternator must be connected to

OHMMETER

FIGURE 26. COIL TEST

INSPECTION

Check battery cells with a hydrometer. The specific gravity reading should be approximately

1.280.

at

80° F, Figure 27. .

SPARK PLUG GAP

0.025" GASOLINE

FIGURE 25. SPARK PLUG GAP

25

SPECIFIC

SRAVITY READING

SHOULD BE

1.280 AT 80° F.

FIGURE 27. SPECIFIC GRAVITY TEST

If one or more cells are low on water, add distilled

water and recharge. Keep the battery case clean and dry. An accumulation

of moisture will lead to a more rapid discharge and

battery failure. Keep the battery terminals clean and tight. After

making connections, coat the terminals with a light application of petroleum jelly or grease to retard corrosion.

Poor contact at the battery cable connections is often a source of

trouble. Make sure battery cables are in good condition and that

contacting surfaces are clean and tightly connected. Do not

reverse battery leads. Use recommended battery tools when disconnecting leads to avoid mechanical battery damage.

26

BATTERY

CHARGING

BATTERY CHARGING, FLYWHEEL

ALTERNATORS

The flywheel alternator natorand uses asolid-state voltage regulator-rectifier for controlling output.

Two different alternator systems and NHCV engines. One the other

A 30-ampere fuse system cables Onan Fuse 321-0162, Buss AGC30

Weak ignition spark trouble engine's charging system, always check for serviceability.

TESTING

Keep these points the flywheel alternator:

1.

•

2.

is a 15

to

protect

are

accidently reversed. Replace the fuse with

in

the charging system. But before testing

OR

Be

sure output control plug (connector) serted properly. Plug must bottom eliminates

tion.

Make sure alternator stator leads are not shorted

together.

any

Keep clean'and tight.

is a

permanent magnet alter-

are

used with

is

a 20 amp Synch ro system,;

amp Phelon system.

is

included

the

alternator

or

in the

a discharged battery indicate

battery charging

in

case

or

equivalent.

SERVICING

in

mind when testing

in

resistance

due to a

•

poor connec-

NHC

the

battery

the

battery

or

servicing

is in-

receptacle-

SYSTEM

3.

Be

sure regulator-rectifier output control

good ground connection. Mating surface

mounting must properly.

4.

Never reverse

Charging system tests require a fully charged battery.

be

clean and fasteners tightened

the

battery leads.

20 AMP SYNCHRO SYSTEM

The

20 amp

separate regulator and a separate rectifier, Figure 28. Testing:

ohmmeter such problems with individual test procedures are listed table

2.

No Output—Stator Assembly: Examine leadwires loose

or rectifier. detecting opens wires that come from alternator stator (two black, one red).

Connect ohmmeter test leads and ground reading should wiring diagram.

Next, connect meter Approximately black lead ground replaced.

and

flywheel alternator systems

For

testing this system,

as

a Simpson"27.0. Various alternator

broken connections

Use the Rxl

in the

to

check continuity.

be

•

0.1 ohm

to

ground.

black leads, stator assembly should

scale

stator. Disconnect-.the three

about

2.0

to

black leadwires and ground.

should

If

no connection exists between

use a

at the

on the

ohms. See Figure 29

be

regulator ohmmeter

to red

The

read from either

has a

for

use a

voltmeter-

in

/

for

and

for

leadwire

ohmmeter

for

be

RECTIFIER

STATOR ASSY.

SCREEN BOLT

TIMING HOLE

FLYWHEEL

PRESSURE COOLE

ENGINE

FIGURE 28. 20 AMP SYSTEM

21

THROUGH

FLYWHEEL

ON

ALTERNATOR ROTOR

(PART

OF

FLYWHEEL ASSY.)

TABLE

2.

TESTING SYNCHRO

TEST

20 AMP

VALUE

SYSTEM

MOUNTED BEHIND BLOWER WHEEL

ALTERNATOR STATOR

Battery voltage - unit not running

Battery voltage with

unit running

rpm

or

at 1800

more

AC voltage from stator with plug disconnected and unit running approximately

at

1800 rpm

Ohmmeter reading when checking stator leads - unit

running

Resistance values (Ohms) between wire pairs.

1.8-2.2x1

two AC

.5-.7

1.3-

LSA

at

not

are as

12 Volts

14.2 Volt

17 volts

Black

plug

follows

•BLACK

•RED

DC

— 14.8*

DC

AC

to

Black

TO TERMINAL

CONNECTOR

RECTIFIER

ASSEMBLY

FIGURE

29. 20 AMP

Full Charge—Will leads

at

connection

SYNCHRO SYSTEM

Not

Regulate: Check

to

regulator plates.

REGULATOR

ASSEMBLY

for

broken

To be regulator winding operates properly, connect lead

to

ground amperes should winding

is

No Charge:

applied

to

red leadwire from regulator terminal.

taped

or

isolated from conducting engine parts. Once

again,

start engine. Alternator should charge

output;

if it

and

start engine. A maximum

be

noted. This would indicate stator

satisfactory.

If

alternator does

battery, shut

If so,

replace regulator.

not

charge when load

off

engine and disconnect one

Be

sure lead

doesn't, replace stator assembly.

to

sure

red

of 4

is

full

*

- 60

Volt minimum

Red

to

Ground.

Checking Rectifier Assembly: Examine each

two diodes

(Rxl scale) from should read

for

breakdown

one

10

ohms diode would read zero resistance short circuit through operation.

An

open diode would read infinite

directions indicating that replacement

Testing Regulator Assembly: voltage regulation, attach and operate engine voltage will climb

to the

at

greater than 2000

by

connecting ohmmeter

black lead

in

proper polarity. A shorted

to

and

the

lead winding when

To

check

at

a DC

about

voltmeter

1800 rpm.

rpm,

white

lead.

would cause

is

necessary.

for

to

preset factory setting (14.2

of the

Meter

in

proper

battery

Battery

14.8 volts).

Some installations ammeter harnesses. Other variations connector voltage readings

in the

may

vary

due to

voltage drop

may

harness

at the

or

loose

or

battery mean poor battery connections.

corroded battery leads.

stem from a loose

in the

length

To test regulator, remove connector. Using

RxlO.OOO scale lead

to red

base.

No in either polarity. Next connect meter leadwire in

one

and

polarity with

of

your ohmmeter, connect one meter

leadwire and other meter lead

to

regulator

deflection should be noted on the ohmmeter

to

black

base

of

regulator. Meterwill deflect fully

no

deflection

in the

other.

a

in

both

to

of

Low

the

15

AMP

The

have

Various alternator problems

PHELON

15 amp

a one

SYSTEM

flywheel alternator systems (Figure

piece regulator-rectifier assembly.

are

listed

in

Table

30)

3.

Testing

With

the

engine running between 1800-2600 observe connect a test ammeter).

proceed with

the

panel ammeter

the NO

(if not

If no

already equipped,

charging

CHARGE TEST.

If shows a constant higher charge rate, follow the HIGH CHARGE RATE TEST procedure.

No Charge Test: Perform

1.

Check

2.

If

to system voltage

the B+ to

voltmeter.

See

Figure 31

voltmeter reads 13.8 volts

(e.g.

to

below

3. Observe ammeter. sider

the

system

does

not

increase, proceed with testing.

4.

Disconnect plug from regulator-rectifier and test

the

AC

voltage

near 3600

volts,

replace the stator.

at the

rpm. If AC

as

follows:

ground voltage using

for

wiring diagram.

or

higher, add a load

headlights)

13.6

volts.

If

charge rate increases,

as

satisfactory.

to

reduce battery

If

charge rate

plug with engine running

voltage reads less than

If

AC voltage is more than

28 volts, replace the regulator-rectifier assembly.

rpm,

is

evident,

ammeter

a DC

con-

28

TABLE

3.

TESTING

PHELON

15 AMP

SYSTEM

BASIC TEST

1:

Battery

2.

Regulator

3. Alternator

• Stator and Wiring with

Fully Charged battery.

4.

Alternator

and Wiring

PROCEDURE

Battery Voltage - unit not running

Battery Voltage after unit is running 3 to 5 minutes

Ohmmeter reading from stator output - unit not running. Check at plug.

Measure AC open circuit stator voltage with unit running. Measure between two stator leads with plug disconnected and unit running at approximately 3600 rpm.

STATOR

TEST VALUES

12 VDC

13.6 to 14.7 VDC

.11 to .19 Ohms

28 VAC

VACU-FLO FLYWHEEL

FIGURE 30. 15 AMP SYSTEM (PHELON)

High Charging Rate Test: Perform this test as follows:

1.

Check B+ to ground voltage with a DC voltmeter.

2.

If voltmeter reads over 14.7 volts, replace

regulator-rectifier assembly.

3. If reading is under 14.7 volts the system is probably okay. Recheck the battery and connections.

If the battery does have a low charge, but

accepts recharging, system is okay.

6 MAGNETS PRESSED INTO

FLYWHEEL (NOT REMOVABLE) .

MOUNTED BEHIND

BLOWER WHEEL

WHITE

TO BATTERY

REGULATOR MUST BE GROUNDED

THROUGH MOUNTING BOLTS

CAUTION !

VOLTAGE .

REGULATOR

RECTIFIER

VRI

VOLT

REG.

RECT

AC AC B+

'Fl

29

FIGURE 31. 15 AMP PHELON SYSTEM

STARTING

SYSTEM

ELECTRIC

CAUTION

starter assembly (Figure 32).

STARTER

To prevent insulation damage, do not use

steam or high pressure water to clean the

FIGURE 32. STARTER ASSEMBLY

REPAIR

DISASSEMBLY

1.

Loosen the M terminal nut on the magnetic switch

and remove the connector. Then unscrew attaching screws and remove the magnetic switch,

Figure 33.

FIGURE 34. REMOVING THROUGH BOLTS

The armature can easily be removed from the front bracket. Be careful not to miss a small steel washer used in the end of the armature shaft. The

shift lever can be removed along with the armature when it is removed: In this case, the spring holder, leverspringsand retainercan betaken out before the lever. See Figure 35.

The packings for the magnetic switch are mounted so that the steel packing is located in the front bracket side.

FIGURE 33. MAGNETIC SWITCH REMOVAL

2.

After removing the thru bolts, the starting motor

can be divided into three parts—the front bracket,

housing and rear bracket. The spacers shown in Figure 34 are used for adjustment of the thrust gap of the armature shaft and are placed between the rear bracket and the commutator.

These washers are inserted so the steel washer is located in the commutator side.

FIGURE 35. REMOVING ARMATURE

Remove the ring after driving the pinion stopper toward the pinion gear using a cylindrical tool as shown in Figure 36. The overrunning clutch and

the pinion stopper should be removed simultaneously.

All four brushes have been soldered to the

brushholder in the same way. The brush springs can be removed from the brushholder.

The pole shoes may be removed if necessary, by

removing the flat head machine screws from the

frame.

30

FIGURE 36. REMOVING RING . .

REASSEMBLY

Inspect the parts carefully in accordance with the procedure described in Inspection of repairs necessary. Reassembly is the reverse, of disassembly. The following precautions should, be taken:

CAUTION

prevent breakdown of lubricant. These parts should be cleaned with a brush dipped in "Varsol" or any other comparable mineral spirits;-Do not immerse overrunning clutch in cleaning solvent. Thoroughly dry any parts that have come into contact with the cleaning

Parts containing lubricated bearings must not be immersed in cleaning fluid to

fluid.

Parts.

Makeany

FIGURE 38. MOUNTING OVERRUNNING CLUTCH*

1.

Inspect brushes (Figure 37) and clean all parts

, carefully with a dry cloth and compressed air if it

is available.

2.

Apply 20 weight non-detergent oil to the armature

shaft and splines. Apply grease (Shell Albania No. 2 or equivalent) sparingly on the shift lever pin,

the joint of the shift lever and plunger, the plunger

and spacing washers-at the end of the shaft.-

3. To mount pverrurinirig clutch,.first insert pinion stopper in. armature shaft; then install ring in groove of the shaft.. For insertion of the

ring,

use tool shown in Figure 38 and pull the pinion stopper up.

4.

Use spacing washers to adjust the armature to

give end play of .004" to .020".

5. Tighten the thru bolts to a torque of 35 to 44 in-lbs.

6. Insert the shift lever as shown in Figure 39 into the front bracket.

FIGURE 37. BRUSHES

FIGURE 39. INSTALLING SHIFT LEVER

31

INSPECTION

1.

Testing Armature for Short Circuits. Place the

armature in a growler and hold a thin steel blade

parallel to the core and just above it while slowly rotating the armature in the growler. A shorted armature will cause the blade to vibrate and be attracted to the core. Replace shorted armature. See Figure 40.

OF

PARTS

3. Testing Armature for Open Circuit. The most likely place for an open circuit to occur is at the commutator riser bars. Inspect the points where the conductors are joined to the commutator bars for loose connections.

4.

Testing Commutator Runout. Place armature in a

test bench and check runout with a dial indicator. When commutator runout exceeds .004", com-

mutator should be refaced (Figure 42).

FIGURE 40. ARMATURE SHORT CIRCUIT TEST

2.

Testing Armature for Grounds. Touch armature

shaft or core and the end of each commutator bar with a pair of ohmmeter leads. If the ohmmeter

reading is low, it indicates a grounded armature. Replace grounded armature. See Figure 41.

FIGURE 42. CHECKING COMMUTATOR RUNOUT

5. Testing Armature Shaft Runout. The armature shaft as well as the commutator may be checked. A bent armature often may be straightened, but if the shaft is worn, a new armature is required

(Figure 43).

FIGURE 41. ARMATURE GROUND TEST

FIGURE 43. CHECKING ARMATURE SHAFT RUNOUT

32

6. Testing Field Coils for Grounds. Place one lead on the connector and the other on a clean spot on the frame after unsoldering shunt field coil wire. If the ohmmeter reading is low, the fields* are grounded,

'either at the connector or in the

windings (Figure 44).

9. Inspection for Brush Spring Tension. Measure brush spring tension with a tension meter as shown in Figure 47. Push the brush and take a reading just as the brush projects a little from the brushholder. On a new brush the spring tension should be 29 to 38 ounces.

FIGURE 47. BRUSH SPRING TENSION TEST

FIGURE 44. FIELD COIL GROUND TEST -

7. Testing Field Coils for Open Circuit. Place one lead on the connector and the other on a clean spot on the brushholder. If the ohmmeter reading

is high, the field coil is open. Check the other

three brushholders in the same manner (Figure

45).

FIGURE 45. FIELD COIL OPEN CIRCUIT TEST

INSPECTION

1.

For no load test, the starting motor is wired as

AFTER

OVERHAUL

" shown in Figure 48 and revolved. The meter

readings for this test should be:

Voltage 11.5 volt

Speed.

3700 rpm minimum .

Current Draw 60 amp maximum

The conductor for this test should be large enough to carry 60

amps and as short as possible. If anything is wrong.in the above test, inspect the following items:

Annealed brush springs

Improperly seated brushes Insufficient armature endplay Shorted, Grounded or open field coil Poor electrical connection Dirty commutator

open or grounded armature

SWITCH

AMMETER

—<A)—

8. Inspection of Brushes. Replace brushes when they are worn less than .3" as shown in Figure46.

See that all brushes move freely in their holders.

rL_m_n

WEAR LIMIT

FIGURE 46. BRUSH WEAR LIMIT

—j-

.3"

.55'

INDICATOR

33

VOLT /-S.

METER (y)

RPM

FIGURE 48. STARTING MOTOR WIRING

BATTERY

2.

Adjusting Pinion Clearance. Connect the battery

to the starting motor as shown in Figure 49. This

•will allow the pinion of the starting motor to slide and stop. In this state, measure the clearance

between the end of the pinion and pinion stopper

when the pinion is pushed lightly toward the

commutator end. Clearance should be .02" to .06".

Adjust for proper clearance by removing the magnetic switch attaching screws and select proper thickness of the fiber packings shown in

Figure 50.

FIGURE 49. BATTERY-CONNECTIONS.

FIGURE 50. ADJUSTING PINION CLEARANCE

34

VALVES

Proper seated valves are essential-to good engine

performance. The cylinder head is removable for valve servicing. Do not use a pry to loosen the cylinder head. Rap sharply on the edge with a softfaced hammer, taking care not to break any cooling fins.

A.conventional type valve spring lifter may be used when removing the valve spring locks, which are of the split type.. Clean all carbon deposits from the

cylinder head, piston top, valves, guides, etc. If a valve face is burned or warped, or the stem wom, install a

new valve.

Worn valve stem guides may be replaced from inside the valve chamber. A seaMs provided behind the

intake valve guides only. The smaller diameter of the tapered valve guides must face toward the valve head.

The valves should not be hand lapped, if at all

.avoidable, since the sharp contact may be destroyed.

This is especially important where stellite faced valves and seats are used. Valve faces should be finished in a machine to 44 degrees. Valve seats should'

be ground with a 45-degree stone and the width of the seat band should be 1/32 to 3/64-of an inch wide. Grind only enough to assure proper seating.-

Remove all ..grinding compound from engine parts and place each valve in its proper location. Check each valve for a tight seat, using an air pressure type testing

tool.

If such a tool is not available, make pencil

marks at intervals across the valve face and observe ifthe marks.rub off uniformly when the valve is rotated

part of a turn against the seat.

Tappets are also replaceable from the valve chamber, after first removing the valve assemblies.

Tha valve face .angle is 44 degrees. The valve seaf angle is 45 degrees:This

1-degree

interference angle

-results in a sharp seating surface between the valve and the top of the.valve seat. The interference angle

method of grinding valves minimizes face deposits

and lengthens valve, life (Figure 51). -

NOTE:

/VOTTT-USE

AUTOMOTIVE TYPE ,

WRENCH TO ADJUST

THE TAPPETS. (&<

^ALVE SEAT" ^INSERT-4

A STANDARD

SEE VALVE TAPPET

isftCLEARANCES IN TEXT-,

Lightly oil the valve stems and reassemble all parts removed.

Adjust the valve clearance.

The positive type valve rotocoils serve to prolong valve life, and decrease valve repairs. Check the rotocoils periodically by removing the cylinder heads and cranking the engine. When functioningproperly, the .valve is rotated

a.

fraction.of a-.turn each time it

opens. If rotocoils are faulty, install new ones.

VALVE-^

/

n ' -

7^

-SEAT

WRONG

[VVALVE

» SEAT

FIGURE 51. VALVE SYSTEM

35

y /

^f*. RIGHT

Tappet Adjustment: The engine is equipped with adjustable valve tappets. The valve tappet clearance should be checked and adjusted, if necessary, at least every 400 operating hours or when poor engine

performance is noticed. Adjust the valve clearance only when engine is at ambienttemperature. Proceed as follows:

1.

Remove all parts necessary to gain access to

valve tappets.

2.

Remove spark plugs to make turning the engine

easier.

3. Use the engine flywheel to turn the engine over slowly by hand until the left hand intake valve opens and closes. Continue turning the flywheel

until the TC mark is on the top and lined up with

the TC mark on the gearcover. Both valves should

be closed. This should place the left hand piston at the top of its compression stroke, the positiQn it must be in to get proper valve adjustment forthe left cylinder.

4.

Clearances are shown in Figure 52 and Tune-up

Specifications. For each valve, the gauge should just pass between the valve stem and valve tappet.

5. To correct the valve clearance, turn the adjusting screw as needed to obtain the right clearance. The screw is self locking.

6. To adjust valves on the right hand cylinder, turn engine one complete revolution and again lineup

mark on the flywheel and theTC mark on the gear cover. Then follow adjustment procedure given for left hand cylinder.

7. Replace all parts removed. Tighten all screws securely. Torque manifold bolts.

FLYWHEEL

Use a suitable puller (with clawsorwith bolts to agree with flywheel) to pull the flywheel.

CAUTION

for mounting the flywheel.

Do not drop the flywheel. A broken fin will destroy the balance. Always use a steel key

INTAKE VALVE

.003

FIGURE 52. VALVE ADJUSTMENT

If a puller is not available turn the flywheel mounting

screw outward about two turns. Use a screwdriver

behind the flywheel to take up the crankshaft end play. Then strike a sharp endwise blow on the head of

the cap screw with a heavy soft-faced hammer to

loosen.

GEAR COVER

After removing the flywheel key and mounting screws, tap the gear cover gently with a soft-faced

hammer to loosen it.

CAUTION

metal lined (smooth) hole or plastic bushing in the governor cup, Figure 53.

The roll pin protrudes upward from the cover and its outer end is 3/4

inch from a straight edge placed across the cover mounting surface.

When installing the gear cover, make sure that the roll pin in the gear cover engages the

'GOVERNOR

SHAFT

GOVERNOR CUP

SO THAT ROLL PIN-

FITS INTO THE

METAL LINED

HOLE OR PLASTIC

BUSHING IN THE CUP

FIGURE 53. GEAR COVER ASSEMBLY

^-GOVERNOR ARM

GOVERNOR SHAFT

GOVERNOR

SHAFT YOKE •

36

(Smooth Side

Towa

rd

Cu p)

OIL SEAL

IF FEELER WILL

ENTER HOLE 1/2'

BALL HAS

FALLEN OUT

Turn the governor cup so that the metal lined hole is at

the three o'clock position. The smooth side of the governor yoke must ride against the governor cup. Turn the governor arm and shaft clockwise as far as possible and hold in this position until the gear cover is installed flush against the crankcase. Be careful not to damage the gear cover oil

GOVERNOR

CUP

seal.

With the gearcover removed, the governor cup can be taken off after removing the snap ring from the

camshaft center pin, Figure 54; Catch the flyballs while sliding the cup off.

WHEN GOVERNOR

IS PROPERLY

ASSEMBLED THE

DIMENSION SHOWN

ON DRAWING WILL

BE AS INDICATED

CAMSHAFT

GEAR

Otherwise, grind off the hub of the cup as required. The camshaft center pin cannot be pulled outward nor removed without damage. If the center pin extends out too far, the cup will not hold the flyballs properly.

PISTON

AND

RINGS

Whenever there is a noticeable wear ridge at the top of each cylinder, remove the ridge before removing the

pistons. If not, the rings can catch the ridge when pushing out the pistons and cause a ring land

fracture. See Figure 55.

CENTER PIN •

SNAP RING —

GOVERNOR CUP

GOVERNOR FLYBALL

FIGURE 54. GOVERNOR CUP DETAILS

1

Replace any flyball that is grooved or has a flat spot. If the arms of the ball spacer are worn or otherwise damaged,

remove the spacer by splitting with a chisel. Replace the spacer with a new one. The governorcup must spin freely on the camshaft center pin without

excessive looseness or wobble. If the race surface of the cup is grooved or rough, replace it with a new one.

When installing the governor cup, tilt the engine so the gear is up, put the flyballs in place and install the

cup and snap ring on the center pin.

FIGURE 55. REMOVING WEAR RIDGE

To remove the piston and connecting rod assemblies; turn the crankshaft until a piston is at the bottom of the stroke. Remove the nuts from the connecting rod bolts.

Lift the rod bearing cap from the rod and push the rod and piston assembly out the top of the cylinder with the handle end of a hammer. Be careful

not to scratch the crankpin or the cylinder wall when removing these parts.

Keep the connecting rod bearing caps and bearings with their respective rods.

The pistons are fitted with two compression rings and

one oil control ring with an expander. Remove these rings from the piston using a piston ring spreader.

Clean thepiston ringgrooves with a groove cleaner or

the end of a broken ring filed to a sharp point. All

passages should be cleaned with a non-caustic solvent. Clean the rod bore and the back of the connecting rod bearings thoroughly.

The camshaft center pin extends out 3/4-inch from the end of the camshaft. This distance provides an in and out travel distance of 7/32-inch for the governor cup,

as illustrated. Hold the cup against the flyballs when measuring. If the distance is less (the engine may race, especially at no load), remove the center pin and press a new pin in only the required amount.

Mark each piston to make sure the rod will be assembled on the piston from which it was removed.

Remove the piston pin retainer from each side and push the pin out.

Inspect the pistons for fractures at the ring lands,

skirts and pin bosses. Check for wear at the ring land

37

using new rings and a feeler gauge as shown in Figure

56.

See Dimensions and Clearances for proper side

clearance measurement and ring groove widths.

Before installing new rings on the piston, check the ring gap by placing each ring squarely in its cylinder, at a position corresponding to the bottom of its travel

(Figure 58). The gap between the ends of the ring is given in Dimensions and Clearances. Rings which are slightly oversize may be filed as necessary to obtain the correct gap, but do not use rings which require too

much filing. Standard size ringsmaybeusedon .005" oversize pistons. Rings that are .010", .020", .030" and .040" oversize are to be used on corresponding

oversize pistons. Ringsof thetapered type are usually

marked fop on one side, or identified in some other

manner and the ring must be installed with this mark

toward the closed end of the piston.

PISTON RING IN

\ CYLINDER BORE

FIGURE 56. RING LAND INSPECTION

Improper width rings or excessive ring side clearance can result in ring breakage. New rings in worn ring grooves don't havegood cylinder wall contact (Figure

57).

CYLINDER

WALL

IMPROPER^

RING

CONTACT:

FIGURE 57. NEW RING IN WORN RING GROOVE

Replace pistons showing signs of bad scoring or burring, lands,

excessive skirt clearance, wavy or worn ring

fractures or damage from detonation. Replace piston pins showing fractures, scored bores or bores out of round more than 0.002-inch.

Use a new piston pin to check the pin bushing in the connecting rod for wear. The clearance should be as shown in Dimensions and Clearances.

ELER GAGE

FIGURE 58. FITTING PISTON RINGS TO THE CYLINDER

Engines that have been fitted with .005" oversize pistons at the factory are identified by the letter E after

the serial number which is stamped on the cylinder

block and on the unit nameplate.

The standard cylinder bore size appears in Dimensions and Clearances.

Space each ring gap one third of the way around the

piston from the preceding one, with nogapdirectly in line with the piston pin. The bottom piston ring groove should be fitted with an expander and an oil control ring and the two upper grooves fitted with compression rings. If a chrome faced ring is used, it will be in the top groove. Theoil control ring is selected forbest performance in regard to the correct unit pressure characteristics.

The piston is fitted with a full-floating type piston pin. The pin is kept in place by two lock rings in the piston,

one at each side. Be sure these lock ringsare properly in place before installing the piston and connecting rod in the engine. Refer to Dimensions and Clearances for the correct piston-to-cylinder clearance.

38

CONNECTING

RODS

Connecting rods should be serviced at the same time as the pistons and rings. Replaceable bushings and bearings are used. Bearings are available in standard or .002", .010", .020" or .030" undersize.

Proper clearance is obtained by replacing the pin bushing and the bearings. The rod bearings are precision size and require no reaming.

Install the connecting rods and caps with raised lines (witness marks) aligned and with the caps facing toward the oil base. The rod and cap numbered 2 fits on the crankshaft journal nearest the bearing plate. Coat the crankshaft journal bearing surfaces with oil before installing the rods. Crank the engine by hand to see that the rods are free. If necessary, rap the connecting rod cap screws sharply with a soft-faced hammer to set the rod square on the journal.

CRANKSHAFT

Inspect the bearing journals. If they are scored and

cannot be smoothed out by dressing down, the

bearing journals should be refinished to use nearest

available undersize bearings or a new crankshaft

should be installed. If a worn main bearing journal cannot be fitted with an available precision type undersize bearing, then refinish it to the next undersize.

If a worn rod journal cannot be fitted by installing new bearing inserts (forged rod), then refinish it to take the corresponding undersize bearing insert available.

Whenever making major repairs on the engine, always inspect the drilled passages of the crankshaft.

Clean them to remove any foreign material and to assure proper lubrication of the connecting rods.

Crankshaft Regrinding: Crankshaft grinding requires a trained, experienced operator, with precision equipment. Onan emphasizes that if facilities or trained personnel are not available, the crankshaft may be sent to the factory.

Special procedures must be observed when rework-

ing crankshafts. In addition to machining, the

crankshaft must be super finished. Shot Peening: On older model engines, shot peening

is required to prevent failures. When the shaft is machined follow the data to shot peen each crank pin

fillet.

1.

Almen gauge reading, .012-A.

2.

Mask off connecting rod bearing areas.

3. Peen with .019" diameter cast steel shot.

4.

Peen for 30 seconds on each crankpin fillet.

BEARINGS

Removal of the camshaft or crankshaft bearings requires complete disassembly of the engine. Use a press or a suitable drive plug to remove the bearings. Support the casting to avoid distortion and avoid damaging the bearing bore during removal and

installation/Use oil on the bearings to reduce-friction

when installing and again lubricate with oil after

installing,

420-0324 to install the camshaft bearings.

PRECISION

Replacement camshaft bearings are precision type

which do not require line reaming or line boring after

installation. Coat the bearing with lubricating oil to reduce friction. Place the bearing on the crankcase

over the bearing bore with the lubricating hole (front only) in proper position. Be sure to start the bearing straight. Press the front bearing in flush with the

outside end of the bearing bore. Press the rear

bearing in until past the ignition plunger hole.

New crankshaft main bearings are precision type

which do not require line reaming or line boring after

installation. They are available in standard size, .002",

.010",

Before putting in the main bearings, expand the

bearing bore by placing.the casting in hot water or in

an oven heater to 200° F. If practical, cool the preci-

sion bearing to shrink it.

For putting in either the front or rear main bearing,

using instructions following, always align the oil

hole(s) in the bearing with the oil hole(s) in the

bearing bore. The oil passage must be at least 1/2

open.

The cold oiled precision bearing should require only

light taps to position it.In the rearbearing plate, install

the bearing flush to 1/64 inch below the end of the

bore using combination driver (same one used for

camshaft bearing). See Figure 60.

Figure 59. Use combination bearing driver

TYPE -DO NOT LINE REAM OR

ALIGN

HOLE IN BEARING

FIGURE 59. CAMSHAFT BEARING

WITH

HOLE-^

IN

BEARING BORE

BORE.

-Vf>V/ FROM

yCJy

OUTSIDE

.020" or .030" undersize.

7/32"

Undersize bearings and connecting rods are available to rework the shaft to .010", .020", and .030" undersize.

If the special combination tool isn't available, it's necessary to

remove the lock pins with side cutters or Easy Out

new bearings are installed, insert new lock pins.

tool.

After the

39

- REAR BEARING END PLATE LOCK PIN

ALIGN BEARING OIL HOLES

WITH OIL HOLES IN BEAR

ING BORE

SHIM

BEARING

PRECISION TYPE- DO NOT LINE REAM OR BORE

FIGURE 60. BEARINGS FOR REAR BEARING PLATE

Engines shipped from the factory have separate thrust washers and main bearings for both front and rear of engine. Front bearing replacement part is a one piece bearing (with attached thrust washer) as shown in Figure 61. Oo not add an additional thrust washer to this front bearing.

NOTE:

Do not add additional thrust washer when replacing front bearing.

FRONT MAIN

BEARING BORE

After allowing three to four minutes for drying, apply the Locktite Bearing Mount from the small tube to the mating surfaces of the bearing and bearing bore. Install the bearing flush with the block using the combination driver just used for the rear bearing. Wipe off any^excess, Locktite around the bearing. Allow at least one hour for hardening at room temperature.

Lubricate the front main bearing lightly with oil and

insert the crankshaft. With the rear bearing plate gasket in place and the rear plate bearing lubricated, slide the thrust washer (grooves toward crankshaft) and plate over the end of the crankshaft. Line up the

notches of the thrust washer with the lock pins before tightening the end plate or the lock pins will be

damaged.

A light film of oil on the thrust washer may hold it in place while

installing the crankshaft.

CRANKSHAFT

ENDPLAY

After the rear bearing end plate has been tightened

using the torque recommended in Assembly Torques and Special Tools, check the crankshaft endplay as shown in Figure 62. If there is too much endplay (see

Dimensions and Clearances for minimum and max-

imum endplay), remove the rear bearing end plate

and add a shim (Figure 60) between the thrust washer

and plate. Reinstall the end plate making sure the thrust washer and shim notches line up with the lock

pins.

Torque and recheck endplay of the crankshaft.

ALIGN BEARING

NOTCHES WITH

LOCK PINS AND MATCH

OIL HOLES

FRONT

MAIN BEARING

DO NOT LINE BORE OR REAM OR BORE

FIGURE 61. FRONT BEARING INSTALLATION

PRECISION TYPE-

Before installing the front bearing, use the Locktite Bearing Mount furnished in the bearing kit. Use the

towelette in the package to clean the outside of the

bearing and the bearing bore in the block.

WARNING

area is well ventilated.

Breathing vapor from towelette and prolong-

ed contact with skin can be harmful. Be sure

MEASURE ENDPLAY HERE

(REFER TO DIMENSIONS

AND CLEARANCES)

FIGURE 62. CRANKSHAFT ENDPLAY

40-

Use heavy fiber or

cup grease in space

between seals to

. improve

seal.

'

REAR BEARING PLATE

MOUNTING FACE

OF GEAR COVER

I 1/32'

THIS SURFACE SHOULD BE

CLEANED OF ALL OLD

SEALING COMPOUND BE-

FORE INSTALLING SEAL.

OIL

SEALS

GEAR COVER

OIL SEAL

A877

GEAR COVER OIL SEAL

FIGURE 63. GEAR COVER AND REAR BEARING PLATE OIL SEALS

The bearing plate must be removed to replace its oil seal.

Drive the oil seal out from the inside using

bearing plate driver and gear cover driver. • Before installing the seals, fill the space between

seals with a fibrous grease or stiff cup grease. This will improve sealing. See Figure 63.

When installing the gear cover oil

seal,

tap the seal inward until it is 11/32 of an inch from the mounting face of the cover.Mnstall new style, thin open face 1-7/64

inches from mounting face of cover.

When installing the bearing plate oil

seal,

tap the seal

seal,

into the bearing plate bore to bottom against the shoulder in the plate bore: Use a seal expander, or place a piece of shim stock around the end of the crankshaft, when replacing the bearing plate to avoid damaging the

seal.

Remove the shim stock as soon as

the plate is in place.

•THIS SURFACE SHOULD BE CLEANED OF ALL OLD

SEALING COMPOUND BEFORE INSTALLING SEAL.

DRIVE OR PRESS OIL SEAL TO SHOULDER OF THE PLATE BORE

REAR BEARING PLATE

OIL SEAL

size rings on a .005" oversize piston. If the cylinder is not being installed, remove any ridge which may have become formed at the top of piston ring travel in the cylinder bore. Engine might be fitted at the factory with a .005" oversize piston and are so indicated by a

letter E following the engine serial number stamped

on the cylinder block and on the unit nameplate.

The standard cylinder bore size appears in Dimensions and Clearances.

OIL

PUMP

To remove the oil pump, it is necessary to detach the

intake cup assembly as shown in Figure 64.

Check the oil pump thoroughly for worn parts. Oil the pump to prime it before reinstalling. Except for gaskets, the component parts of the pump are not available individually. The suction cup is available separately. Install a new pump assembly, if required.

Engines equipped with some types of reduction gear assemblies do not use the rear oil

seal.

The reduction gear assembly is oiled directly from the engine crankcase. Referto the instructions screened on the case of the reduction gear assembly.

CYLINDER

The cylinder wears very little in normal service. If,

through improper lubrication or accident, the cylinder wall should become scored or worn badly, the cylinder may be rebored and honed to accommodate a new piston and ring set of the available oversizes. Pistons are available in .005", .010", .020", .030"

and .040" oversize. Piston rings are available in

:010",

'.020", .030" and .040" oversize. Use standard

OIL PUMP INTAKE CUP

—^mm

CRANKCASE TURNED

ON LEFT SIDE,f

UNSCREW OIL PUMP ASSEMBLY^. FROM INTAKE CUP AT THIS POINT \V To reassemble reverse the procedure.

OIL PUMP ASSEMBLY-*

FIGURE 64. OIL PUMP ASSEMBLY

41

-~( (if

:

CYLINDER

Remove the cylinder heads for cleaning at least every

400 hours or when poor engine performance is

noticed.

1.

Use a 1/2 inch socket wrench to remove cylinder

,head bojts. Lift heads off.

CAUTION

2.

After removing heads, clean out all carbon

deposits. Be careful not to damage the outer

sealing edges where gaskets fit. The heads are made of aluminum and can be damaged by careless handling.

3. Use new head gaskets and clean both the heads and the cylinder block thoroughly where the head gaskets rest.

4.

Place heads in position and follow head torque

tightening sequence shown in Figure 65. Start out tightening all bolts to 5 ft-lb, then 10 ft-lb, etc.,

until all bolts are torqued tb 17-19 ft-lb.

5. Recheck torque before engine has run a .total of 50 hours.

HEADS

Do not remove heads when they are hot.. Warpage may occur.

3(6

1

LEFT CYLINDER

FIGURE 65. HEAD BOLT TIGHTENING SEQUENCE

RIGHT CYLINDER

7

42

PARTS

CATALOG

For parts Authorized Onan Parts

To avoid errors Always refer

1.

Always give

or

service, contact

or

delay

to the

nameplate

the

MODEL

INSTRUCTIONS

the

dealer from whom

and

Service Center.

in

filling your parts order, please furnish

on

your unit:

and

SPEC

FOR

NO. and

ORDERING

you

SERIAL

0 OfiSH.

MODEL AND SPEC

SERIAL

NO.

IMPORTANT-^EN^OWERWO^BTS

CHECK

OIL

LEVEL CHANGE OIL

BELOW ABOVE FOR

OIL

CAPACITY

30oF----

30oF

EXTREME TEMPERATURES. SEE SERVICE

MANUAL

BATTERY

MANUFACTURED

DIVISION

MINNEAPOLIS, MINNESOTA,

OF

DAILY

EVERY

[

SAE iOW

SAE

OPERATING

L

ONAN

ONAN CORPORATIO

99.Q6fi3-,-

REPAIR

purchased this equipment

NO.

PARTS

all

information requested.

IQ,

NO.

100

HOURS

QTS

30

YOUR

VOLT

BV

U.S

4o

or

refer

to

your Nearest

. >•

For handy reference, insert "YOUR" nameplate information

2.

Do

not

order

by

reference number

3 Give

4 State definite shipping instructions.

-Prices import duties, sales taxes, exchange rates,

For current parts prices, consult your Onan Dealer, Distributor "En esta lista

de Consiga

the

part number, description and.quantity needed ofeach item. Ifan older part cannot

return the part prepaid

address plainly on the package. Write a letter to the same address stating the reasonfor returning the part. promptly against

packing list indicates items

are

purposely omitted from this Parts Catalog

de

partes

los

precios, derechos aduanales, impuestos

los

precios vigentes

to

your dealer

the

transportation company making

are

los

precios se omiten de proposito, ya que bastante confusion resulto de fluctuaciones

de su

or

group number; always

or

nearest AUTHORIZED SERVICE STATION. Print your name and

Any

claim

back ordered.

etc.

de

distribuidor

in

the spaces above.

use

part number

for

loss

or

damage

the

delivery. Shipments

due

to

the

or

venta, cambios extranjeros,

de

productos "ONAN".

to

confusion resulting from fluctuating costs,

Parts

and

your unit

and

in

are

Service Center.

etc."

description.

be

transit should

complete unless

43

identified,

be

filed

the

This catalog applies to the standard NHC and NHCV Engines as listed below. Parts are arranged in groups of

related items. Each illustrated part is identified by a reference number corresponding to the same reference number in the parts list for that group. Parts illustrations are typical. Using the Model and Spec No. from the nameplate,' select the Parfs Key No.

This Parfs Key No. represents parts that differ between models. Unless otherwise mentioned in the description,

parts are interchangeable between models. Right and left sides are determined by facing the blowerend (front) of

the engine.

'(1,

2, etc., ih the last column) that applies to your Engine Model and Spec No.

ENGINE

MODEL

£ - The Specification Letter Advances (A to B, B to C, etc.) with manufacturing changes.

* - The factory code number portion of the specification number

AND

SPEC

NHC-MS/*A

NHC-MS/*B

indicates standard equipped engines and/or customer selected optional equipment.

NO. £

PARTS

KEY NO.

1

2

DATA

MODEL

TABLE

AND

NHCV-MS/*A NHCV-MS/*B

SPEC

NO. £

PARTS

KEY NO.

3 4

44

13

12 16

CRANKSHAFT

REF.

NO.

.

4

•

9

10

PART

NO.

1

.

£

KEY, SHAFT

515-0198

2

515-0001

3

515-0002 515-0098

104-0032

5

104-0043

6

518-0014

7

134-0673

8

FLYWHEEL ASSEMBLY - Key 1 & 2 (Includes Ring Gear)

134-2464

134-2462 134-2467

FLYWHEEL ASSEMBLY - KEY 3 & 4 (Includes Ring Gear)

.. 134-2768

•134-2770 134-2769

AND

QTY.

USED

1

1 1

FLYWHEEL

PART

DESCRIPTION

Crankshaft 11

1

Crankshaft Stub .

1

Crankshaft Gear

1

Flywheel

1 1

Flywheel

1

Gear, Washer, Gear Retaining 16 821-0010 3

1 1 •

Ring, Ring Gear (Part

1

Standard With Magnet Ring (Phelon

1

With Magnet Ring (Synchro

1

Standard With Magnet Ring (Phelon

With Magnet Ring (Synchro

- Key 1, 3

- Key 2, 4

Crankshaft

Retaining - Gear

Fly Wheels) 17 821-0014 .2

12

Amp

20

Amp

12

Amp

20

Amp

of all

Alternator) Alternator)

GROUP

45

.

12

13

REF.

NO. NO.

15

£ - Order

PART

526-0262 850-0055 1

104-0170

134-2433 1 134-2384- 1

by

Engine Serial Number.

Description, giving Model, Spec

QTY.

USED

Washer, Flat, Steel (7/16")

1

Washer, Lock, Steel (7/16") Screw, Special (Flywheel-

1

•

Mounting) Guard, Guard,

'

Optional Screw, Locking

Flanged,

Key Screw, Locking

• Flanged.Steel (5/16-18 Key 1,

DESCRIPTION

Flywheel Flywheel

Steel (1/4-20

1,2

2

PART

.

- Key 1,2

- Key 1,2- '

Hex

Head,

x 1/2") •

Hex

Head,

x 1/2")

and

CYLINDER

REF.

NO.

8 9

10

11 12

PART

NO.

2

123-0954

3

123-0952

4

123-0865

5

110-1624

6

110-1720

7

517-0048 520-0736

110-1731

HEAD,

CYLINDER 110-1912 110-1913

809-0035

BEARING,SLEEVE 101-0420 101-0420-02 101-0420-10 101-0420-20 101-0420-30

BLOCK

1 1 1

1

1 1 1 1

GROUP

QTY.

USED

Cap & Valve, Breather

"Tube,

Cover, Valve Compartment

Gasket, Valve Cover 'Plug, 'Stud,

Gasket, Cylinder Head

Right Side

Left Side

Screw, Round Head Sheet

CRANKSHAFT REAR

"Standard

.002"

.010"

.020"

.030"

PART

DESCRIPTION

Block Assembly, Cylinder

(Includes Paris Marked

Breather

Baffle,

Breather Tube

Expansion Bearing Plate Mounting

Metal

(#8 x 3/4")

Undersize Undersize Undersize Undersize

*)

REF.

NO.

13 104-0575 14

15

16 17 18

19

20

46

PART

NO.

101-0415

'PLATE,

101-0439 101-0417

101-0405 509-0041 516-0072 NUT, 104-0091

104-0091 WASHER, FLAT 526-0063

526-0250 526-0251 526-0066

1

BEARING - REAR

HEX

QTY.

USED

AR

'Washer, Thrust - Crankshaft

Bearing

'Gasket, Bearing Plate

1 Standard 1 Special

2 'Bearing, Sleeve - Camshaft 1 'Seal, 4

5 'Bearing Plate Mounting

20 Cylinder Head Mounting

2 Copper (1/4") - Valve

20 Steel (3/8") - Cylinder

5 Steel (3/8") - Bearing 2 Copper (3/8") - Cylinder

Gear Assembly)

'Pin -

Cover Mounting Head'Mounting

Plate Mounting

. Block

Oil -

Bearing Stop

PART

DESCRIPTION

(Use

with Reduction

Crankshaft

REF.

NO.

21 • 120-0680 • 22 110-1974 23 24

25

2627 110-0539 28 110-0639 29

30 31

PART

NO.

110-1719

INSERT, VALVE SEAT 110-1716 110-1716-02 IIO1!

716-05 110-1716-10 110-1716-25 INSERT, VALVE SEAT 110-1933 110-1933-02 110-1933-05 110-1933-10 110-1933-25 110-1939

TAPPET,VALVE 115-0006 115-0006-05 110-0904 SCREW, HEX HEAD, CAP, STEEL 800-0011

806-0027 821-0010

QTY.

USED

1 2 2'

2 'Standard 2 2 2 2

2 "Standard 2 ' 2 2

2 4 4

8

4 Standard

4

4 Roto Cap

2

1

PART

DESCRIPTION

'Tube,

Oil - Crankcase

Valve,

Intake

Valve,

Exhaust 33

-EXHAUST 34 .002"

Oversize 35

.005"

Oversize 36

.010"

Oversize

.025"

Oversize

-INTAKE 37 .002"

Oversize

.005"

Oversize

.010"

Oversize

.025"

Oversize

"Guide, Valve 38

Spring,

Valve

Lock, Valve Spring 39

.005"

Oversize

1/4-20

x 2" - Valve £ -

Cover Mounting

3/8-16-x

1/4-20

3/4" - Cylinder Block

x 1/2" - Key 3 & 4 -

Timing Pointer

REF.

NO.

32

AR -

* -

PART

NO.

123-0951 1 Clamp, Loop - Breather 123-0958 1 . Screen - Breather Tube

509-0117 1 Seal "O" Ring - Breather

110-0068 .2 "Gasket - Valve Guide (Intaike) STUD-CYLINDER HEAD MOUNTING 520-0717 8 3/8 x.1-7/8"

520-0773 • 12 3/8 x 2-5/16"

BEARING, SLEEVE- FLANGED, CRANKSHAFT 101-0432 1 "Standard

101-0432-02 1 . 002" Undersize 101-0432-10 1 010" Undersize 101-0432-20 1 .020" Undersize 101-0432-30 1 030" Undersize 104-0776 AR Shim

160-1190 -1 Pointer, Timing - Key 3 & 4

Order by description, giving complete Model: Spec and Engine Serial Number. Quantity as Required. Parts Included in Block Assembly.

QTY.

USED

Tube Cap

Tube

(.005")

Thrust

PART

DESCRIPTION

- Crankshaft

OIL

BASE

GROUP

REF.

NO.

10

PART

NO.

1 £

102-0646

2

800-0051

3

505-0056

4

TUBE,

5

6 7

8 9

£ - Order by description, giving complete Model,

OIL FILL 123-1117 123-1272 123-1276

141-0078 CAP&INDI 123-0527 123-1290 123-0191 821-0010

850-0050.

Spec and Engine Serial Number.

QTY.

USED

Base,

1 1 Gasket, Base 4

1 .1 Standard - Key 1 & 2

1 1

1

CATOR.OILFILL

1 • Standard.- Key 1 & 2 1 Special - Key 3 & 4

1 Gasket, Oil Fill Cap

2 4

Oil

Screw, Hex Head, Cap, Steel

(3/8-16 x

Plug,

Drain

Standard - Key 3 & 4 Special - Key 3 & 4 - (Used

with Pulse Type Fuel Pump

Gasket, Fill Tube

Screw, Hex Head, Cap, Steel

(1/4-20 x 5/8")

Washer, Lock, Steel (3/8)

PART

DESCRIPTION

1-1/4")

47

PISTON

AND ROD

GROUP

REF.

NO. NO.

* - Parts Included in Piston and Pin Set.

t - Parts Included in Connecting Rod Assembly:

PART

PISTON AND

1

112-0141 122-0141-05 112-0141-10

112-0141-20 112-0141-30 112-0141-40

*PIN,WRIST-

2

112-0112 112-0112-02

518-0294 4

3 4 114-0203

805-0010

5

114-0036 2

6

BEARING, HALF SLEEVE-CONNECTING ROD

7

114-0188 114-0188-02 114-0188-10 4 114-0188-20 114-0188-30 RING SET, PISTON

8

113-0165 2 Standard 113-0165-05 113-0165-10 2 113-0165-20 113-0165-30 2 113-0165-40

QTY.

USED DESCRIPTION

PIN SET (Includes Parts Marked *)

2 Standard

.005"

2 2 2 2 2

PISTON

2 2

2 Rod Assembly, Connecting 4

4 Standard 4

4 4

2 2 2

Oversize

.010"

Oversize

.020"

Oversize

.030"

Oversize

.040"

Oversize

Standard

.002"

Oversize

'Ring,

Retaining - Wrist Pin

(Includes Parts Marked t) fBolt, Rod Cap fBushing,

.002"

Undersize

.010"

Undersize

.020"

Undersize

.030"

Undersize

.005"

Oversize

.010"

Oversize

.020"

Oversize

.030"

Oversize

.040"

Oversize

PART

Sleeve - Wrist Pin

CAMSHAFT

REF.

NO.

1

105-0382

2

105-0075

3

515-0001 1 Key - Camshaft Gear 4 105-0004 1 Washer, Thrust 5 105-0332 1

6

510-0015 5

7

150-0612 8 150-0078 1 9 150-1257 1 tSpacer, Fly Ball

10 150-0077 1

* - Parts Included in Camshaft Assembly, t - Parts included in Camshaft

GROUP

PART QTY. PART

NO.

USED

1 1

1

Camshaft (Includes Parts

Marked *)

'Pin,

Camshaft

Gear,

Camshaft (Includes

Parts Marked t)

Ball,

Fly - Governor

Cup,

Governor

Ring,

Retaining

fPlate,

Fly Ball

Gear.

DESCRIPTION

48

7—23

GEARCASE

REF.

NO.

PART

NO.

1 GEAR CASE ASSEMBLY (All Include Parts Marked t)

103-0386 1 103-0472 103-0447 103-0474 103-0387

103-0446

103-0475

103-0473

•BEARING, (Upper Governor Shaft) 510-0013 1 Needle - Key 1,3 510-0105 1 Sleeve - Key 2, 4

•SHAFT & 150-1260 1 Standard - Key 1 150-1450 1 Standard - Key 2 150-1436 1 Standard - Key 3 150-1451 1 Standard - Key 4 150-1453 1 Special - Key 2 (Side Pull)

GROUP

QTY.

USED

1

1 1 1

1

ARM,

GOVERNOR

PART

DESCRIPTION

Standard - Key 1

(Includes Parts Marked *)

Standard - Key 2

(Includes Parts Marked *)

Standard - Key 3

(Includes Parts Marked *)

Standard - Key 4

(Includes Parts Marked *)

Special -.

Special - Key 3, 4 - Without

Special - Key 2 - Side Pull Governor

Special - Key 2 - Includes

Key.1, Governor Parts - Manual Throttle •

Governor Parts - Manual

Throttle

(Includes Standard Parts Marked ')

Dust Seals & Standard Parts Marked *)

2 - Without

QTY.

REF

NO.

8 9

10 11 12

13

14 15 16 17

18

19 20 21

22

23 815-0181

* - Parts Included in Specific Gearcase Assemblies,

t - Parts Included in all Gearcase Assemblies.

PART.

NO.

150-1187 815-0046

516-0130 510-0008

'

510-0014

EXTENSION„GOVERNOR ARM 150-1073

150-1268 • 1 •

150-0755 150-0752 509-0008

103-0408 509-0040 516-0011SCREW, HEX HEAD, CAP, STEEL 800-0032 800-0034 526-0065

PART

USED

DESCRIPTION

•Yoke,

1

2

1 1 1

1

1 1 1

1 Gasket, Gearcase 1 2

4

. 1

5

1

Governor Shaft

'Screw, Pan Head, Steel

(8-32 x 3/8")

•Pin,

Roll

•Bearing, 'Bearing,

Standard - Key 1, 2 - Left Optional - Key 1, 2 - Rear

Optional - Key 1,2 - Front Optional - Key 1, 2 - Right

•fSeal, 'Seal,

Needle - Key 1, 3 Ball

Pull Pull Pull

Pull

Oil Oil - Crankshaft

Pin,

Roll

5/16-18 x 1-3/4" 5/16-18

x 2-1/4" Washer, Flat, Copper (5/16") Screw, Hex Head, Cap, Thread

(10-32x1/2")

49

OIL

SYSTEM

REF.

NO.

1 120-0491

10

11 12 13 14

PART

NO.

120-0648 801-0050

120-0140 120-0398

526-0066

120-0161

815-0194

DRAIN, 122-0352

122-0360 122-0347 122-0320 122-0321 122-0323

309-0010

GROUP

OIL

QTY.

USED

PART

DESCRIPTION

Pump,

Oil

(Parts

Not

Cap,

Pump

Cap,

Filter

Pressure

Sold

Steel

Thread

-

Separately)

Intake,

Oil

Screw,

(3/8-24 Spring, Valve, Washer, By-Pass Valve Gasket Screw,

Cutting with Lock Washer

(10-32 Key 1,'

Key

Seal,

Adapter, Gasket - Adapter Mounting Filter,

Switch,

Optional

Pump

Hex

Head,

xl")

By-Pass Valve

By-Pass

Kit - Oil

Hex

Head,

x 3/8")

2

3, 4

Air - Oil

Oil

Filter

Oil

Low Oil

REF.

NO.

15 502-0058 16 193-0198

17 526-0065 2 18

800-0028 505-0057

19

20 193-0031

21

193-0068

193-0107

22

501-0004

23 24 502-0005 1

25

502-0020 800-0007

26 27

850-0040

50

PART

NO.

QTY.

USED

1

Tee 1 2

1 1 1 1

1

1 2 2

Switch - Optional Sender, Washer, Flat, Copper (5/16") Screw,

(5/16-18

Plug, Clamp, Meter Gauge, Gauge,

Optional

Line, Elbow, Pipe

Elbow, Pipe Screw, Washer, Lock, Steel (1/4")

DESCRIPTION

- Low Oil Oil

Hex

x 1")

Pipe (1/8")

Oil

Pressure (Electrical)

Flexible Optional Optional

Hex

(1/4-20

x 1")

Pressure - Optional

Head,

Pressure - Optional

- Oil

Head,

PART

Pressure

Cap,

- Oil -

Optional

Line Line

Cap,

Steel

-

Steel

FUEL & EXHAUST

REF.

NO.

10 11 12 13 14

PART

NO.

149-1223

1

505-0313 1 Elbow, Pipe - Carburetor

2

LINE,

3

4

5

6

7 8 9

15

16 17 18

19

20

21 22 23

24 25

26 27

28 29

30

31

32

33

34

35 36

37

38 39 40

41

FUEL-PUMPTOCARBURETOR

149-1228 503-0708 502-0313

502-0002

CARBURETOR, GASOLINE (See Separate Group for Parts)

141-0802

141-0803

155-1217 141-0281

520-0526

154-1466 154-1483 149-0045 149-0003 153-0263

800-0538

868-0002 854-0017

806-0009

800-0512

850-0045

154-1484 154-1482 154-1492

155-1219 154-1493

850-0050 805-0018

862-0003

153-0097

149-0136

526-0043

800-0004

149-1322

149-1321

503-0301

149-1364

813-0102

870-0131 503-0706

153-0464

518-0176

QTY.

USED

1

SYSTEMS

Pump, Fuel - Key 1 & 2 -

(See Separate Group for Parts) Inlet - • 3

1 Standard - Key 1, 2 1 Special - Key 3, 4 - Optional 1 Elbow, Pipe - Key 1, 2-

1 Elbow, Pipe - Key 1, 2-

1 1 1 1

2

1 2 1 2 1

4

2 2

2

4

4 2

2 1

2

4

Fuel Pump Outlet Fuel Pump Inlet

Standard - Manual Choke Special - Electric Choke

Muffler, Exhaust Gasket, Carburetor Mounting Stud, Manifold, Gasket, Intake Manifold Spacer, Fuel Pump - Key 1, 2 Gasket, Fuel Pump - Key 1, 2

Bracket & Clamp - Manual

Choke - Optional

Screw, Hex Head, Cap

(3/8-16 x Nut, Hex, Jam (5/16-24) Washer, Lock, Steel (5/16) Screw, Counterbore, Cap,

Steel (1/4-20 x Screw, Hex Head, Cap, Steel

(5/16-18 x 1") Washer, Lock, Steel (5/16) Adapter, Exhaust Manifold Gasket, Exhaust Manifold Manifold,

Profile (Side Outlet) -

Optional Clamp, Exhaust Pipe Manifold,

1

2

1

2

1

2

Profile (Top Outlet) Optional

Washer, Lock, Steel (3/8")

Bolt, Place, Steel

(3/8-16 x 1") Nut, Hex (3/8-16) Choke, Control, Manual -

Optional

Cover - Fuel Pump Block

Opening - Key 3, 4 Washer, Flat, Copper (1/4) -

. Key 3, 4

Screw, Hex Head, Cap, Steel

(1/4-20 x 5/8") - Key 3, 4

Pump, Fuel - Optional -

Key 3, 4 (See Separate

Group for Parts)

Cap,

1

1 1

2 1

1

Key 3, 4

Clamp, Loop - Key 3, 4 Bracket, Angle - Fuel Pump -

Key 3, 4

Screw, Round Head, Steel

(10-32 x 5/8") - Key 3, 4 Nut, Hex (10-32) - Key 3, 4 Line, Bracket, Angle - Manual

Choke - Key 3, 4 Clip,

Key 3, 4

GROUP

PART

DESCRIPTION

Carburetor Mounting

Intake

1-1/2")

1-1/4")

Exhaust - High

Inlet - Fuel Pump -

Flexible - Key 3, 4

Cable - Manual Choke -

4 1

TsMJ

51

CARBURETOR

REF.

NO.

2 3

4

10 11 12 13 14 15 16 17 18

19 20 21 22 23 24

PART

NO.

CARBURETOR, GASOLINE

141-0802 141-0803

1

141-0708 141-0741 141-0698

141-0813

5

141-0705

6

141-0661

7

141-0798

141-0811

8

9

141-0703 141-0702 141-0701 141-0700 141-0711 141-0713 141-0710 141-0077 141-0810

SHAFT, CHOKE 141-0742

141-0679 141-0699 141-0697 141-0203 141-0809

141-0799 141-0281

PARTS

QTY.

USED

GROUP

DESCRIPTION

Standard - Manual Choke Special - Electric Choke

Bowl,

Fuel

Plate.

Screw, Round Head-with

Washer

Plate,

"Retainer, Seal

"fSeal,

"Seat, Valve

fWasher, Valve Seat

"Shaft, Float Pivot

Float, Carburetor

"tGasket, Bowl

Screw, Throttle Stop Spring,

"Needle, Idle Adjusting

Spring,

"fWasher, Main

Jet, Main (Adjustable) Manual Choke

Electric Choke

"Washer, Shaft - Manual Choke

"fSeal,

"Retainer, Seal - Manual Choke

Shaft, Throttle

"Spring,

"tGasket, Carburetor Flange

•-H.-

Choke

Throttle

Rubber

Throttle Stop Idle Adjusting Needle

Felt - Manual Choke

Fuel Float

PART

18

Jet

* - Included

t - Included

FUEL

PUMP

in

Repair

in

Gasket

PARTS

Kit

#141-0814.

Kit

#141-0748.

GROUP

(MECHANICAL

0>-5

TYPE)

REF.

NO.

149-1223

1 2

815-0148

815-0147

3

4

149-0096

5

149-0095

6

149-0582

7

149-0672 149-0539

8

149-0675

9 10 516-0113 11

12 '149-0670 13 149-1148 14

149-1042 15 509-0065 16 149-1044 17

149-0003

518-0129

18

149-0858

19

PART

NO.

—

QTY.

USED

1 1

PART

DESCRIPTION

Pump, Fuel Body,

(Not Sold Separately)

Screw,

Steel,

Dip (8-32

Screw, Oval Head, Cross

Recess, Steel, Thread

Cutting (6-32 "Valve, "Gasket, Valve "Diaphragm, Fuel Pump "Spring,

Retainer, Check Valve Spring, Pin, Body, Lower - Fuel Pump

(Not Sold Separately) Link, Rocker Arm,

Lever, Prime Seal, Spring,

"Gasket, Pump Mount

Ring,

Lever

'Gasket, Diaphragm - Optional

(Prevents

- Key 1, 2

Top -

Fuel Pump

Hex

Head, Slotted,

Zinc Plated, Cromate

x 7/8")

Arm

Air

x 7/8")

Lock)

Check

Diaphragm

Pump

Rocker

O-Ring

Prime Lever

Retaining - Prime

52

* - Included

in

Repair

Kit

#149-0526.

AIR

CLEANER

REF.

NO.

10 11

12 13 14

PART

NO.

1 140-1175 2 140-1185

3 503-0170 4 HOSE, FLEXIBLE-BREATHER

503-0582

123-1241

5 CLAMP, LOOP

503-0365 503-.0274

6 CLAMP, LOOP

503-0004 503-0368

7 140-1186

8 140-1282

9 815-0199

850-0030 ADAPTER, CARBURETOR INLET

145-0398 145-0453 140-0921517^0009 800-0003

GROUP

QTY.

USED

1

1 2

1 Key 1, 2 1 Key 3, 4

1 1 2

Filter,

1

Gasket, Clamp, Hose

1

Key

1 Key 3, 1

Key 1,2

1 Key 3,

1

Key 1,2, 3

1 Key

.1 Elbow, Carburetor Inlet

1 Elbow, Carburetor Inlet 3 Screw, Fillister Head, Steel

Gasket, Carburetor Inlet Plug, Button Screw,

PART

DESCRIPTION

Air

Cleaner-

Disposable

Air

Cleaner

.

1,

2

4

4 • •

4

Key

1,2

Key 3,

4

(10-32 x 5/16")

Washer, Lock, Steel

- Key

Hex

' (1/4-20x1/2")

Head, Cap, Steel

(#10)

1,

2

REF.

NO.

15 16

17 193-0218" .•

18 19 20

-

21 22 PANEL, AIR CLEANER

23 SCREW

24 870-0160 25 140-1280

PART

NO.

862-0001 853-0013

302-0885 322-0108 821-0010

526-0015

140-1179 140-1184

809-0059 821-0010

QTY.

USED

Nut,

2 2

1

.

1 •

2 Light, Indicator 4 Screw, Locking Head, Flanged,

4 Washer, Flat, Steel

1 Standard 1 Optional

2 Round Head, Steel, Sheet 2 Locking Head, Flanged, Steel 2

Nut,

1 Bracket,

Hex (1/4)

Washer, Lock, External

Tooth,

Panel,

Optional

Meter,

Key Optional Steel (1/4-20

Key

with Variable Speed Governor)

Metal (1/4-20 (1/4-20

Speed

PART.

DESCRIPTION

Steel

Instrument

Time Totalizing

1,2-

1,2 1,2

(1/4)

- Key 1,2-

Optional

- Key 1,2 '

- Key 1, 2

x 1/2") - Key 4

(1/4) - Key 3, 4

Air

Cleaner

-

- Key 1, 2-

x 1/2) -

(1/4) - .

(Used

x 1/2") - Key 3

- Key 3, 4

53

IGNITION

GROUP

REF.

NO.

10 815-0403

11

12 13

14

PART

NO.

1

815-0358

2

160-1149

3 160-1148

4 SCREW

815-0373

802-0034

5 850-0038

6 160-1151 7 160-1150

8 160-1158

9 336-2132

850-0025 312-0069 870-0221

815-0405

15

160-1154

16

821-0010

17

16618 19 20 21

0617

167-

0240 167-1463 167-1462 166-0535

QTY.

USED

PART

DESCRIPTION

Screw,

Hex Steel, (8-32 x 5/16")

'Cover, Breaker 'Gasket, Cover

Fillister Head, Cross-Recessed,

Steel, Tooth Lockwasher

(1/4-20

Socket Head, Steel

(1/4-20 Key

Washer, Lock, Steel

Key Plunger Gasket Breaker Assembly (Includes

Parts Marked

'Lead,

to Coil

'Screw,

Thread Forming

(8-32 x 5/16") 'Washer, Lock, Steel 'Condenser *Nut,

External Lockwasher (8-32) 'Screw,

Recessed, (8-32

"Point

Screw, Locking Head, Flanged,

Steel (1/4-20

Clamp, Coil Mounting'

Spark Plug

Cable, Electrical - Spark Plug Cable, Electrical - Spark Plug Coil,

Head, Slotted,

Thread Forming

Box

with External

x 5/8") - Key 1, 3 x 3/4") -

2, 4 2, 4

Electrical - Points

Pan

Head, Steel,

Hex,

Steel, with

Pan

Head, Cross-

x 1/2")

Set,

Breaker

Ignition

(1/4) -

*)

(#8)

Steel

x 1/2")

REF.

NO.

22

PART

NO.

LEAD, 332-0592 336-2271

336-2272

336-2273

336-0794

300-0140

23

302-0270

24

302-0060

25

812-0082 2

26

27 850-0025

860-0008 2

28

332-1043 1

29

332-0604 1

30

332-1273 1

31

SCREW

32

813-0100 2

821-0004

856-0003

33 34 301-3530

167-0188 1

35

338-0619

36

336-2132

37

" - Parts Included

QTY.

USED

ELECTRICAL

1

1 1

2

1 1 1

in

Breaker Assembly.

PART

DESCRIPTION

Jumper - Optional Switch

to

Starter Solenoid

Optional

Switch

Optional

Switch

Optional

Ammeter

Optional

Switch,

Optional Clamp, Meter - Optional Ammeter.- Optional Screw, Round Head, Cross-

Recessed, (8-32

Washer, Lock, Steel

Nut, Hex, Steel (8-32)

Jumper, Terminal

Block, Terminal Strip,

Round Head, Cross-Recessed,

Steel (10-32

Hex Locking Head, Flanged,

Washer, Lock, Steel

Bracket, Terminal Block Clip, Harness, Wiring - Starter

Lead,

.

to

Ignition Coil

to

Terminal Board

to

Terminal Board

Toggle - Ignition

Steel

x 3/4")

Marker

Key 1, Steel (10-32 x 5/16").-

Key 2, Key 1,

Cable

Solenoid

Electrical - Terminal

Block

x 1/2") -

3

4

3

to

Terminal Block

to

Ignition Coil

-

(#8)

(#10) -

54

CHARGING

REF.

NO.

PART

NO.

1 813-0108-

850-0030

191-0885

4

821-0018

5 191-08866 821-0010

7-

191-1059

8 336-2192

9 813-0108

ALTERNATOR

QTY.

USED

Alternator Group - Phelon

12 Volt

15 Amp

Flywheel with Magnet Ring,

Illustrated

and Flywheel Group;

Parts Marked

"Screw, Round Head, Cross-

Recessed,

(10-32 x 1-1/4") "Washer, Lock, Steel "Stator, Alternator

15 Amp "Screw,

Hex

Flanged,

(1/4-20 x5/8") "Regulator, Voltage "Screw,

Hex

Flanged,

(1/4-20 "Bracket, Mounting, Regulator "Lead,

Electrical - Regulator

to Terminal Board

Alternator Group - Synchro

12 Volt

Flywheel with Magnet Rings

Illustrated

& Flywheel Group;

Marked fScrew, Round Head, Cross-

Recessed,

(10-32 x 1-1/4")

GROUP - OPTIONAL EQUIPMENT

PART

DESCRIPTION

(Includes

in the

Crankshaft

*

Steel

(#10)

- 12

Volt,

Locking Head,

Steel

Locking Head;

Steel

x 1/2")

20 Amp

f)

(Includes

in

Crankshaft

Steel

and

-

Parts

REF.

NO.

10 11

.12

13 14 15

16

"

17

18

19 20 21

22

23 24

£ - Factory Installed Optional Equipment. When Ordering

* - Parts Included f - Parts Included

PART

NO.

850-0030-

191-0937

821-0004

191-0938 191-0939 , 821-0010

191-1060

336-2222 1 336-2236 323-0488

323-0496

323-0880 323-0879 323-0882 323-0881

Parts give Complete Engine Model, Spec

Serial Numbers.

.-

QTY.

USED

1

..1.

in 12 in

12 .Volt

PART

DESCRIPTION

3

fWasher, Lock, Steel

1

fStator, Alternator

4

1

2

1

5

1

1 1 1

20 Amp

fScrew,

Hex Flanged, (10-32x5/16")

fRectifier, Current fRegulator, Voltage fScrew,

Flanged, (1/4-20x1/2")

.

fBracket, Mounting, Rectifier

Regulator fLead, f

Lead,

fContact, Electrical - Female,

Connecting

•-

•fContact, Electrical - Male, Connector

fShelirConnector fShell, fShell, fShell,

Volt

15 Amp 20 Amp

Locking Head,

Steel

Hex

Locking Head,

Steel

Electrical - Optional Electrical - Optional

Connector Connector Connector

Alternator Group. Alternator Group.

(2 (2 (3 (3

and

(#10)

- 12

Volt

Sockets) Pins) Sockets) Pins)

-

'

-

55

GOVERNOR GROUP

STANDARD GOVERNOR

(CONTROLLED AT ENGINE)

VARIABLE

(CONTROLLED AT ENGINE) - OPTIONAL

SPEED

GOVERNOR

VARIABLE

(REMOTE CONTROLLED)

SPEED

- OPTIONAL

GOVERNOR

-39

56

QTY.

-

USED

1 2

4 5-

PART

NO.

£•

520r0623 870-0053

526-0196 870-0131

£

REF.

NO.

-. .

.. 3 150-0939

6 fSTUD, LINK ASSEMBLY

520-0187 520-0690

7 870-0053

150-0639 •

8

870-0131

9

150-0098 •

10

150-0147

11

STUD,

12

13

14 150-1359 15

16. 17 . 821-0010

18 19

20 21 22

SPEED ADJL 150-0096 150-1418 870-0131

821-0010

150-1433

£

152-0095

800-0005

526-0015

152-0041 870-0065

• 2

v 1

PART

DESCRIPTION

. Linkage Assembly, Governor -

•1

1

2

2 2 2

1

Used on Engines up thru Serial Number832097 (Includes Parts Marked *) - Key. 1 thru 4

'Stud,

Link Assembly • 'Nut, Hex (3/8) "Joint,

Ball,

•Washer, Flat (#10) 'Nut, Hex with External

Lockwasher (10-32)

Linkage Assembly, Governor -

Nylon

Used on Engines Starting with Serial 832098 and up

(Includes Parts Marked t) Key 2, 4

1

Key 2 Key 4

1

tNut, Hex (3/8) - Key 2, 4'

tJoint,

Ball,

2

fNut, Hex with External "

2

Steel - Key 2, 4

Lockwasher - (10-32) Key 2; 4

Spring,

Governor

Stud,

1

Speed Adjustment -

Key 1, 2

TMENT

Key 3

1

Key 4

1

Nut, Hex with External

Lockwasher

Bracket, Speed Stud - Key 1, 2

1

. Screw, Locking Head, Flanged,

1

Steel (1/4-20 x 1/2") Key 1, 2

Bracket, Speed Stud - Key 3, 4

1

Screw, Locking Head, Flanged, •

2

Steel (1/4-20 x 1/2") Key 3, 4

Control,

1

Variable Speed

Governor - (Includes Parts

Marked #) - Optional - Key 1, 2

#Arm,

1 1

Control

#Screw, Hex Head, Cap, Steel

(1/4-20 x 3/4")

#Washer, Flat, Steel (1/4)

2

#Washer, Spring Tension

1

#Nut, Hex, Steel (1/4-20)

2

REF.

NO.

- 23 .815-0199 •>

PART

NO.

QTY:

USED

2

•

#Screw, Fillister Head, Steel

PART

DESCRIPTION

(10-32x5/16".) •

24.

870-01.31

.25 152-0190

-26 800-0003

27

856-00.06

28 .862-0001 •

, - 2

#Nut, Hex with External

2

Lockwasher (10-32)

#Bracket, Control

1 •

Screw, .Hex Head, Cap, Steel

2

(1/4-20 x. 1/2") - Key 1, 2

Washer-, Lock, External Tooth,

Steel (1/4) - Key 1, 2

Nut, Hex, Steel, Zinc Plate

2 .

(1/4-20) - Key 1, 2

£ 1 .

Remote Control, Variable

Speed Governor (Includes

Parts Marked +) - Optional Key 3, 4

150-1214 1

29 30 518-0176 31 150-1343 32 516-0059 33 526-0006 34 815-0104 1

35 152-0155

812-0066

36

+Spring, +Clip,

1

+Bracket, Cable

1.

+Pin,

1

+Washer, Flat, Steel (#6)

1

+Screw, Fillister. Head, Steel +Swivel,

1

+Screw, Round Head, Steel

1

Governor

Cable

Cotter

(8-32 x

5/16")

Cable Holding

(6-32x3/4")

37 38 39

150-1398 150-1435

821-0010 •

1 1

2

tSpring, +Arm,

Idle Setting

Governor Control

Screw, Locking Head, Flanged,

Steel(1/4-20 x 1/2") -

• Key 3, 4 Washer, Flat, Steel (1/4) -

40 526-0214

1

Key 3, 4

4.1 ••

150-1269

1

Bushing,

Control Arm-•

Key 3, 4

£ - Not Stocked as an Assembly; When Ordering give

Complete Engine Nameplate Model, Spec and Serial Number and/or Order Individual Parts.

' - Parts Included in old type Nylon Ball Joint

Throttle Linkage.

t - Parts Included in new type Metal Ball Joint

Throttle Linkage.

# - Parts Included in Engine Mounted Variable Speed

Governor.

+ - Parts Included in Remote Controlled Variable

Speed Governor.

57

HOUSSMG GROUP

58

REF.

NO.

•2 HOUSING

- 8 821-0010

10 815-0370

11 140-1193

12 140-1192"

13 .405-1935

PART

NO.

1 134-2489*-

: • 134-2494

134-2811

'134-2531

134-2810 HOUSING

134-2488 134-2799 134-2483

134-2487

870-0107 809-0059

9 815-0261

QTY.

PART

USED

DESCRIPTION

1 Housing,

BLOWER

1

Standard

1

Standard

1

Optional - With Flywheel

1 Optional - With Flywheel

AIR-RIGHT SIDE

Key Key

Support, Housing - Right Support, Housing - Left

Nut, Speed (#14A)

Screw, Round Head, Sheet

• Metal

Screw, Locking Head, Flanged,

Screw,

Shield,

-Shield,

• Carburetor-Optional - Key 1,

• Hood, Engine - Optional

Air -

Key 1,

2

- Key 1

- Key 2

Guard

- Key 1

Guard

- Key 2

1

2 Side-Key Side-Key

(1/4 x 1/2") -

Key 1,

2

Steel (1/4-20

Key

3, 4

Hex

Steel,

Thread Forming

(1/4-20 x 7/16")

Hex

Thread Forming

(1/4-20

x 1/2") - Key

Heat, Left Side

Carburetor - Optional - Key

Heat, Right Side

Kev 1.

2

Left Side

1,2 1,2

x 1/2" ) -

Washer Head,

Head, Steel,

-

- Key 1, 2

1,

- •

•

-

.

2

1,2

2

REF.

NO.

14 405-1872

15 818-0150

16

526-0003

17 821.-06T0

18 134-2755

19 134-2752

20 134-2761 21

22 23

24 517-0021

25 SCREW

26 870-0106

27 821-0010 28 815-0261

29 821-0010

PART

NO.

134-2763 134-2747 134-2737

809-0059 820-0010

QTY.

USED

2 'Clip, Hood - Optional 4 "Rivet, Drive - Optional 4 ' "Washer, Flat - Optional

'2 Screw, Locking Head, Steel,

1 Housing, 1 Housing, 1 Scroll, 1 Guard, Scroll

1 Backplate, Scroll 1 Housing, Blower 1 Plug, Button

2 Round Head, Sheet Metal, 2 Locking Head, Flanged, Steel,

2 4 Screw, Locking Head, Flanged,

4 Screw,

5 Screw, Locking Head, Flanged,

Key 1, Key 1, Key 1,

Thread Forming

(1/4-20 Key 3, Key

Key

Steel Thread Forming

(1/4-20

Nut,

Steel (1/4-20 Steel,

(1/4-20 x 7/16")

Steel (1/4-20

3, 4

Air

3, 4

(1/4 x 1/2") - Key 3

Speed (#T4Z)

Hex

Thread Forming

PART

DESCRIPTION

2 2 2

x 1/2") - Key 1, 2 Air -

4

Air -

(Includes Guard)

- Key 3, 4

x 1/2") - Key 4

Washer Head,

- .

-

Left Side Right Side-

x 1/2) - Key 3, 4

x 1/2") - Key 3, 4

-

- Key 3, .4

- Key 3, 4

- Key 3

- Key 3, 4

-

59

STARTING MOTOR PARTS GROUP - KEY 1, 3

REF.

NO.

191-0734

1 191-0742

2

191-0743 191-0744

3 4 191-0745

191-0746

5 6 191-0747 7

191-0748

8 191-0749 9 191-0750

10

191-0751 191-0752

11 12

191-0753

PART

NO.

QTY. PART

USED DESCRIPTION

1 Motor, Starting - Key 1, 3 1 Yoke Assembly (Includes

Parts Marked *) 1 Armature, Starter 1 Clutch - Pinion Gear, Starter 1 Stop, Pinion Gear 1 Ring, Retaining 1 Washer, Thrust 1 Bracket, Starter - Front

(Includes Bearing) 1 Lever, Clutch 1 Spring, Helical, Compression (A) 1 Spring, Helical, Compression (B) 1 Holder, Spring 1 Bracket, Starter - Rear

(Includes Bearing)

22

27

REF.

PART QTY. PART

NO.

NO. USED DESCRIPTION

75 191-0754 1 Washer, Flat

14 191-0755 1 Washer, Flat 15 191-0756 1 Insulator, Disc 16 191-0757 4 'Brush, Starter 17 191-0758 4 Spring, Helical, Compression

18 191-0759 2 Bolt, Machine (Through)

19 191-0760 3 Screw, Machine, Pan Head 20 191-0761 1 Solenoid, Starter 21 191-0762 1 22 191-0763 1 Bearing, Sleeve (Front) 23 191-0764 1 Bearing, Sleeve (Rear)

24 191-0765 4 'Shoe, Pole, Field Coil

25 191-0766 4 "Screw, Machine, Pan Head

26 850-0050 2 Washer, Lock, Steel (3/8)

27 800-0051 2 Screw, Machine, Hex Head,

'Coil,

(Brush)

Field, Starter

Steel (3/8-16 x

1-1/4")

* - Included in Yoke Assembly.

60

STARTING

MOTOR

PARTS

GROUP - KEY

2, 4

191-1052

• 191-0983

1

191-0984

2

191-1010

191-1011

4

191-0987 191-0988

6

.191-1086

7

191-0971 191-0991

PART

NO.

REF.

NO.

••

3

•

. 5

-.10 191-1007

QTY.

USED

1 1 1 11 1

2. 1

1

.

PART

• DESCRIPTION

Motor,

Starting

Lever,

Clutch Spring - Plate Bearing, Screw

Set Solenoid,

Bolt, Machine (Through) Bracket, Starter - Front

(Includes Bearing) Bearing,-Sleeve (Front) Stop - Retaining

Gear

•Spring, .(Brush)'

- Key 2, 4 •

Set-

Sleeve (Rear)

Clutch

Set,

Helical, Compression

•

Pinion

-'

•

QTY.

USED

' •

2

1

-

1 .

1

2

•1

'

1

,

2 2

REF.

NO

11 12 ..191-1009

13 14 15 16 17-• 191-1006

18

19 850-0050

20

PART

.

NO.

191-1008

.

191-1087 191-1088 191-0997 191-1005

191-1089

800-0051

• - Included in'Brush Holder.

PART

DESCRIPTION

'Brush,

Starter (Negative)

Bracket, Starter - Rear

(Includes Bearing) Clutch --Pinion Armature, Starter Washer - Insulator Brush,

Starter (Positive)

Holder, Brush (Includes

Parts Marked

Coil,

Ffeld, Starter

(Includes Positive Brushes) Washer, Lock, Steel

-Screw, Machine. Steel (3/8-16 x.1-1/4")

Gear,

Set

')

-

Hex

Starter

(3/8)

Head,

~

61

24

26

THERMO-MAGNETIC

REF.

NO.

10 526-0018 1 Washer, Flat, Steel (5/8") 11 870-0134 1 Palnut (1/4-20) 12 153-0399 Insulator, Disc 13 153-0400 1 Bimetal - Heater Assembly 14 518-0129 1 15 332-0876 1 16 336-1550 1 17 336-1549 1

18

PART QTY.

NO.

1 153-0385 1 2 153-0386 1 3 153-0389 1 Cover, Choke 4 153-0391 1 5 153-0395 1 Armature, Solenoid 6 307-0801 1 7 153-0392 .1 Frame, Solenoid 8 153-0387 1 9 153-0390 1

854-0017

USED

1

CHOKE

Plate,

Mounting

Housing, Core,

Solenoid

Coil,

Solenoid

Spring,

Armature

Lever,

Limit

Ring,

Retaining Terminal, Lead,

Electrical - Ground

Lead,

Electrical - Solenoid

Washer, Lock, Internal

Tooth (5/16)

GROUP

PART

DESCRIPTION

Choke

Lug - Ground

- OPTIONAL EQUIPMENT

REF.

NO.

19 526-0022 20 21

22 526-0008 1 23 850-0030

24

25 854-0007 2 Washer, Lock, Internal

26

PART

NO.

864-0002 1 Nut, Hex (5/16-18) 813-0107

812-0076

815-0161

153-0429

QTY. PART

USED DESCRIPTION

1 1 Screw, Round Head, Steel

1 2

2 Screw, Flat Head, Steel

1

62

Washer, Flat, Steel (5/16")

(10-32x1-1/4") Washer, Flat, Steel (#10) Washer, Lock, Steel (#10) Screw, Round Head, Steel

(8-32 x

5/16")

Tooth (#8)

(10-32 x 3/8")

Kit, Replacement (Includes

Complete Choke, Less

Electrical Leads, and Carburetor Air Horn Gaskets)

FUEL

PUMP

PARTS

GROUP

(PULSE TYPE)

- OPTIONAL

REF.

NO.

•4

PART

149-1322 142-0537 1

1

142-0540 2

2

149-1323

3

142-0541 . 1 142-0545

5

NO.

QtY.

USED

1

1. 1

PART

DESCRIPTION

Pump, Fuel Valve Plate Assembly Screw, Cover Gasket, Base Gasket, Valve Plate Spring,

Pump

REF.

NO.

PART

NO..

6 149-1326

7 149-1324 8 142-05529 142-0555

QTY.

USED.

1 1

1 l'

PART

DESCRIPTION

Cover, Pump

Base,

Pump Disc,.Pump Diaphragm, Pump

63

SIDE

MOUNTED

FUEL

TANK

GROUP

(OPTIONAL EQUIPMENT):

12.

10-

REF.

NO.

10 193-0207 11

12 870-0053

PART

NO.

1

159-0981 159-0596

2

159-0595

3

134-0599

4

501-

5 6 7 8 9

0008

159-0007

504-

0013

505-

0057

502-

0020

813-0108

QTY. PART

USED DESCRIPTION

1 Tank, Fuel 2 Strap, Fuel Tank 2 . Bracket, Fuel Tank

Clip,

Fuel Line

Line,

Fuel

Cap,

Fuel Tank

Valve,

Shutoff

Plug,

Pipe

Elbow, Fuel Pump

Line

1

Cap and

2 Screw, Machine, Round Head,

2

Fuel Tank Cross Recessed, Steel

(10-32 x 1-1/2") Hold-down Strap

Nut, Hex

(1/8)

Gauge Assembly,

(10-32)

to

Fuel

Bracket

P.

CLUTCH

REF.

NO.

1

190-0171

2

515-0196

3

STUD,

520-0738 1 3/8-16 x 4" 520-0739 2 3/8-16 x 3"

190-0288 190-0289

GROUP

PART

NO.

1 1 Key,

CLUTCH HOUSING

1 1

(OPTIONAL EQUIPMENT)

QTY.

USED

PART

DESCRIPTION

Adapter, Clutch

Clutch Assembly Clutch

Clutch

TO

ENGINE

Kit Clutch, Hardware

to

Includes Complete

Adapter, Mounting

and

Engine

Instructions

64

62625

REDUCTION

1 2 3 4

5 6 7

8 9

14 15 16 17 18 19

PART

NO.

190-0290 190-0300 516-0012

190-

0020 191- 0021 190-0016 190-0115

509-

0016

190-0195

515-0142

190-0191

510-

0022

190-0190' 515-0159 518-0013

190-0202

190-0192

515-0103

REF.

NO.

10 11 12

13 510-0021

GEAR

USED

GROUP

QTY.

PART

DESCRIPTION

Reduction Gear Assembly Housing, Pin,

Dowel Gasket - Housing Gasket - Cover Plate, Shim

Following Sizes: .005",

.012", Seal, Washer, Pinion Gear

Key, Pinion Gear

Gear, Pinion

Race,

(Cup)

•• Race, Inner with Roller Bearings - (Cone)

' Gear, Helical, Drive

Key, Woodruff

Ring, Spacer, Bearing Shaft, Take

Key, Woodruff

(OPTIONAL EQUIPMENT)

Gear Assembly

to

Engine

to

Off,

Power

SERVICE

Housing

Retaining - Bearing

Set

(Includes 1 Each

.016", .020", .025")

Oil

Outer, Roller Bearing

Retaining

.009"

KITS

of

-

AND

MISCELLANEOUS

REF.

NO.

20 21 22

23 24

25

26 27

28 29

30 31

• 32 33

34

PART

NO.

510-0023 510-0024 518-0172

505-0007

190-0306 800-0007 526-0063

805-0009

800-0028 526-0045

190-0297

190-0298

800-0026 526-0065

505-0054

'•

-

QTY.

USED

1 1 1

1 2

4 4

4

8

2

PART

DESCRIPTION

Race,

Inner with Roller

Bearings - (Cone)

Race,

Outer, Roller Bearing

(Cup)

Vent

. Reducer, Pipe Gasket - Bearing Plate

Housing Cover

Screw,

Steel (1/4-20

. Washer, Flat, Copper

Bolt,

Hex

(5/16-18

Screw,

(5/16-18

•Washer, Flat, Copper (5/16)

•

Bracket, Support, Housing

1

Nut

1

2 2

Bar,

Screw,

(5/16-18

Washer, Flat, Copper (5/16)

• Plug, Pipe

(1/4 x 1/8")

Hex

Head,

x 1")

Head, Steel

x 1")

Hex

Head, Cap,-Steel

x 1")

Support Bracket

Hex

Head,

x 3/4") (1/4) •

•

to

Cap,

(1/4)

Cap,

-

•

Steel

NOTE:

For Additional Kits, referto the Applicable

Parts Group

PART

98-1807 168-0122 168-0121

160-1161 522-0265 525-0137

525-0305

NO.

in

Question.

QTY.

USED

Kit, Decal Kit, Gasket, Complete Engine

Kit, Gasket, Carbon Removal Kit, Ignition Tune-Up Kit, Engine Overhaul Paint, Touch-Up, Metallic

Green

(16 oz.

can)

Paint, Touch-Up, Non-Metallic

Green (13 oz. Pressurized

65

PART

DESCRIPTION

pressurized

Can)

WIRING DIAGRAMS

The wiring diagrams in this section are typical for NHC and NHCV engines with 15-or20-annp flywheel alternators and other options. The separate engine control wiring diagrams shipped with each unit should be used for troubleshooting. The following drawings are included herein:

Engine Control Wiring Diagram with options 67 _ Engine Control Wiring Diagram with

Thermo-Magnetic Choke (622-0270) 68

Wiring Diagram for Flywheel Alternator

(Phelon 15 Amp) 69

Wiring Diagram for Flywheel Alternator

. (Synchro 20 Amp) 69

66

fi

1

S2.

SI

r

(SEE

Wl

^

M

TBI

START

-o o

B+

ALT

IGN

J

E4

0"

1

BTI

1

i-x

SYNCHRO ALTERNATOR

20 AMP

MOUNTCD

BIWUO

Gl

'<«*•.• S

REF

Df.S.

E4

'

Bl

BTI CRI El.2

E3 Gl

Ml" M2

SI

SZ

S3

S4

Tl

TBI

VRI

Wl

*

WHEN USED

REGULATOR MUST BE GROUNDED THROUGH MOUNTING BOLTS

CAUTION!

MOUNTED BEHIND BLOWE* WHEEL

LIST < =*?«•)

CriOKt-ELtCTRlC STARTER i SOLENOID -ENOINE

BATTERY RECTIFIER ASSY SPARK PLUG

SENDER ALTERNATOR

AMMETER METER - O'L PRESSURE "iwiTCH - START SWITCH - IGNITION BREAKER

SWITCH - LOPKO COIL - IGNITION Bl OCK-TERMINAL

STRIP - MARKER

REGULATOR-VOLTA&E

JUMPER

DCSCKlPTiGN

-12 V.

- OIL

PRESSURE

&. CAP.

(SEE

ASSEMBLY

•

NOTE

0

VRI

VOLT RECT

AC AC

REG

~L

B+

NOTE;

I. REMOVE JUMPER (Wl), WHEN

AMMETER (Ml) IS USED

OP

-o o-f 1

•rai

ALT

^

n

^o—-o-

^Fl

PHELON

15 AMP

ALTERNATOR

ENGINE CONTROL WIRING WITH

DIAGRAM

OPTIONS

oo

START

SWITCH

(WH!^

USED)

THERMO "M/iCv.

CHOKE

(MHLN

USED)

STOP

SWITCH

^ MOUNTED ON

BLOWER

HOUSING

BREAKER CAP.

ASSY'

£

i

LOW OiL PRESSURE

(WHEN

ENGINE

CONTROL WIRING DIAGRAM CHOKE

(622-0270)

WITH

13

THERMO-MAGNETIC

4^

I

<5>-

WIRING

DIAGRAM

ALTERNATOR

FOR

FLYWHEEL

(PHELON 15 AMP)

MOU WTC D BtHIUD

augtR

uwecu

I

STMOR

y

\

St&ULWOR MUST Bt

VRI

•VOLT

VAOUMTIHC, BOLHi

KIC,

tta

—

CMrrion-.

El ZZ

I

1

RUN)

——oLi

OFF

Tl _

.

I

I BTI

S3

REF oes.

81 911

fl I 2 Fl

Gl

11

SI

n

Tl

vm

(622-0386)

PARI NO.

Oil

.!

1

I

lit SCD IH 10(1 STARTER ( SOIENO10-ENGINE 3ATTERY. 1? V

SPARK

nuc

FUSE.

35 A«P HOlOtR-fUSE ALTERNATOS-FITIHEEL- 15 ASP

CONNECTOR SIITCH-START.RUN.OFF

BREAKER I CAP ASSEMBLT

IGNITION C0ll-(0N»N) REGULATOR-RECTIFIER-VOLTAGE

MouMTto ttmm

s [

.

fin

4 \ /

*.

3

VRI

r'

Cl " ZZ

I BTI

WIRING

DIAGRAM

ALTERNATOR

REX PES

' Bl"

^RTl " ."

_-tl,"E\_

E3

Jl

".Ml"

_SI

S3

Tl

vei_

~WI

Gl

PART NO.

\_

na-oioe

I13-010T

FOR

FLYWHEEL

(SYNCRO 20 AMP)

(622-0382)

•

ffl

DE.V.R\PTION

STARTER t, SOLENOID-LVI& BATTt'RV.IZV _ RECTIFILR ASSY

SPARK"

PLUG" ~ TH"!!

StNDER • OIL PRL"isUttC: • CONNECTOR

I •

CONNEJCTOR - FAVOM

METER-OIL PfttSVORE "~T"

SWITCH-START SWITCH -\GW BREAtEK t CAP AASV

_IGUn\ON_C.OIL

KEGULMOC -

LEAD A^SY

I ALTER WATOR - FLYWHEEL 70 MAP

I

VOLTAGE"

-

1 1

69

-

„-w-„

B1

CUSTOMER

#|

^-^

SERVICES

OWNER'S

ENGINE

WARRANTY

DRIVEN

SEPARATE GENERATORS,

SERVICE

ELECTRIC

INDUSTRIAL

-

GENERATOR

ENGINES

SETS,

QUALITY

Onan products are engineered and designed to perform as stated on product nameplate and published specification. the equipment

GENERAL

All

Onan-manufactured engine-driven electric generator are sold satisfactory performance of the product when properly installed, serviced, and operated under normal conditions, in

the Onan Operator's Manual

Warranty

•

properly

covered in this

model,

Warranty tors or their Approved and Registered Service Dealers. A complete and Service Product. necessary

Material Station which

OF

PRODUCT

With

proper installation and operation, regular maintenance and periodic repair service,

will

provide reliable service.

WARRANTY

with a full

according to the manufacturer's instructions. The text of the Onan published warranty

Registration: A Warranty Registration card accompanies

filled

out and returned to the Onan Factory in order to

bulletin.

and serial number of the equipment.

Authorization: Warranty service must be performed by Onan Factory or Onan Authorized

Centers

These

Allowances: Onan

or his Approved Service Dealer, all genuine Onan parts used in a warranty repair of

fail

Onan Authorized Service

facilities

to perform as warranted.

PRACTICES

sets,

separate

one-year warranty. This warranty is issued

sent

with

the product.

When requesting warranty repair

is provided in our brochure F-115, a copy of

Centers

and tools for the service and repair of Onan equipment.

will

allow

credit or furnish free of charge to the Onan Authorized Service

have

work

you must provide the

trained service personnel, parts stock, and the

generators, and industrial

only

to the

each

Onan Product. This card must be

qualify

listing

of

which

original

for warranty consideration as

these

is supplied

user

purchase

Onan Authorized

with

engines

and promises

appears

date, Onan

Distribu-

Parts

each

Onan

these

products

Labor

Allowance: Onan and his Approved Dealer at straight time labor when the material ule of published work for travel adjustments, tune-up adjustments or parts maintenance items, and sequential

Administration: territory Dealers are authorized to make settlement of all customer warranty claims facturer's warranty

Onan

or factory workmanship. This labor allowance

flat

not covered by warranty

allowance of

time and/or mileage,

damages.

Warranty of Onan Products is administered through Onan Authorized Distributors in whose

the equipment is located.

reserves

the

will

rate

labor allowances, or, otherwise a time judged

expenses

policy

right

as described herein.

to

allow

warranty repair credit to the Onan Authorized

will

be charged to the owner. The

such as start-up

unit

removal or installation

These

change

warranty practices

cause

will

be

charges,

Distributors and their Approved or Registered Onan Service

communication

expense,

without

of failure is determined to be defective

based

on the factory's standard time sched-

reasonable

Onan's

prior

Warranty practice

charges,

cost of

does

notice.

Parts

and Service Center

by the factory. Repair

does

not provide

transportation

fuel,

oil, normal maintenance

not cover incidental or con-

within

the

limits

charges,

of the manu-

MAINTENANCE

A

Planned Preventive Maintenance Program is extremely important if you are to receive

tion

and

long

service

failure

or permanent

tains recommended maintenance

life

from

'damage

your Onan

to your equipment. The Onan Operator's Manual

schedules

unit.

Neglecting routine maintenance can result in premature

and procedures.

sent

with

efficient

the product con-

opera-

£2%

Maintenance is

.

1. Operator Maintenance performed by the operator.

2.

Critical

Regular maintenance this

scheduled maintenance must be offered when applying for a warranty

INSTALLATION

Installation

manufacturer's recommendations. If the owner experiences any ventilation, whom

he purchased the equipment so that corrective action can be taken. Distributor difficulties,

MSS-22B Replaces 23B054 and MSS-22A Rev.

7-2-73

divided

Maintenance performed

is extremely important and all Onan Products should be installed in accordance

exhaust location,

and his Approved or Registered Service Dealers may be able to remedy certain installation

such repair

into

will

work

two categories:

only

by

h'elp you

avoid

sudden and costly repairs in the future. Adequate evidence of

fuel

lines,

is not considered Onan warranty and there

wiring,

etc., he should immediately contact the company

qualified

difficulty

service personnel.

claim.

with

such items as mounting,

Although

will-be

Onan

Minneapolis,

the Onan Authorized

a charge for this service.

Minnesota 55432

with

the

from-

u

fllMAIM

WI • A DIVISION OF ONAN CORPORATION

1400 73RD

AVENUE

N.E. • MINNEAPOLIS, MINNESOTA 55432

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ONAN

940-1011

(8-10-73)

,2

Use

these

Industrial

same

instructions with

Engines

as

the

NHC,

GENERAL

The

NHCV

numerous

required

industrial

enclosed

by

the

vacu-flo cooling

VACU-FLO COOLING

The

vacu-flo

air

into

equipped engine

the

engine shroud

SUPPLEMENTARY

Operator's

with

but

pressure

has a

engine

vacu-flo cooling

(Figure

applications.

engine

application

system.

and

INSTRUCTION

cooling

1)

However,

uses

an

over

Manual

is

must

provide for adequate

integral

the

AND PARTS CATALOG

and

system.

designed

any

inlet

flywheel-centrifugal

cooling

Parts Catalog

The NHCV

to run

and

fins

outlet

and

940-404,

engine

cool

and

openings

ventilation

surfaces

NHC

is

basically

efficiently

or

through

fan to

of

the

pull

engine.

the

in

ducts

the

cool

Figure

flywheel

upward,

scroll

starter

'^ivuxioN^ T^

2. The

fan.

left

or

(Figure

motor.

heated air

The

scroll

right

3) has

The

ie

oui^et

scroll

direction.

four

0

is

directed

may be

identical

outlet

f

vacu-flo scroll rnust

through

positioned

This

is

holes

has a mesh

'^^^-^^-^ will result. Engine overheating lock

to

scored pistons

Should a vacu-flo

problem

1.

are:

Air

inlet

is

2. Air discharge opening

and

engine

chronically

obstructed

cylinders.

overheat,

or

too

small

is

partially

blocked

systems.

3.

Recirculation

of

heated air

into

fresh

an

air

tight

to

discharge heated air

possible

shaped

because

to

fit

type screen for

not be

can

to

air

cause troubles ranging from vapor

the

most

allow

proper

by

external

inlet.

scroll

the

over

which

back

the

end of

safety.

restricted

likely

or

sources

ventilation.

ducts

or

encases

in the

section

downward,

of

the

overheating

of

the

exhaust

v

the

INSTALLATION

The vacu-flo

in

Tet' and larger The area of the air or outlet If radius-type

When airflow sectional long ducts should be covered

than the engine

louvers are

opening should be located as close to the engine as possible.

the duct length

a duct is

area

runs, screens or the exhaust pipe.

installation

outlet

(not square-type)

area of the duct

openings, and permits the use of a

itself.

inlet

used,

used

must

the

inlet

exceeds 5 feet,

between

be at

least

with

permits greater

must

be at

opening

elbows

the

as large as the

must

asbestos tape.

freedom

least

increase duct size 30%. Use no

if it is necessary to

scroll

be increased if air flow is

141 sq.

must

discharge and the

be increased accordingly. The air

.Exhaust

in choice of

compartment

inch.

scroll

discharge. The cross

pipes running

If a

change

outlet

locating

only

filter,

restricted

inside

slightly

more

air flow

vent, its

the air

grille,

than two 90°

direction.

free

by

bends,

Vacu-Flo

The

safety commensurate Provide a short duct or opening, to absorb If

operation in advisable. TIMING Engine

gap.

Setting

the

engine. Dynamic from the viewer to the flywheel scribe from 25° BTC.

The

timing

made

accessible by removing the

screen

with

Cold

VACU-FLO

timing

is the

pointer

used safety

canvas

cold

weather

ENGINE

advanced

point

(engine running) may be less accurate

to cover vents

standards.

section

vibration.

weather

can

or retarded by opening or

gap at

is

mounted

between

is

likely,

cause

0.020

on the

right

overcooling if air flow is not regulated.

inch is the

cylinder

hand

must

be 1/4 inch

the engine air

installing a shutter

most

mark

and

timing

block

shroud.

mesh

outlet

closing

accurate

because

pointer

above

or

larger,

and the

in the air out is

the breaker

method

the

sight

may vary - 2°

the

oil

filter;

and

external

point

of

timing

angle

it is

SCROLL

•

FIGURE

1.

NHCV

INDUSTRIAL

AIR OUT

ENGINE

8189

FIGURE 3. VACU-FLO SCROLL POSITIONS

OIL FILTER

FIGURE 2. AIRFLOW

VACU-FLO SYSTEM

THROUGH

25° BTC MARK TIMING POINTER

:ON FLYWHEEL)

FIGURE 4. VACU-FLO ENGINE

DYNAMIC

TIMING

940-1011

(9/73)

Parts

in

of/or

in

940-404.

NOTE:

REF.

Parts

not

NO.

5

11

this

list

addition

that

illustrated.

apply

to

those

are

similar

PART NO.

123B1117 123B1234

SUPPLEMENTARY PARTS

to the

listed

in

LIST

NHCV

Industrial

in the

appearance

OIL

QTY. USED PART

Operator's/Service

BASE

Engines.

to

those

GROUP

in the

Tube, Oil Tube, Oil

Pulse

Use

DESCRIPTION

Type

these parts

Manual

main

parts catalog

Fill - Standard Fill - Units

Fuel

and

Parts Catalog

Pump -

in

place

with

Optional

are

REF.

NO.

2 3 7

PART NO.

103B446

103B447

510P105

150B1436

Delete

GEAR COVER

QTY. USED

1

GROUP

*Bearing, *Shaft § Arm,

PART

DESCRIPTION

Standard

tapped Stator) - Includes parts

Manual

Includes tapped Stator)

Governor

for

Throttle

for

Flywheel

Oil

Seal

Flywheel

Governor

(Drilled

Alternator

Controlled

(Drilled

Alternator

Shaft (Upper)

and

marked

Engines

and

*

r

?

/

i

(

REF. 7 NO.

8 13 14 15

PART

NO.

Delete Delete Delete Delete FLYWHEEL

134B2768 134B2770

CRANKSHAFT

QTY. USED

AND

1 1

FLYWHEEL

GROUP

PART

DESCRIPTION

Standard

Units (Includes

Units with

System

Magnet

(Includes Ring ) -

Flywheel

Ring

Optional

Ring

Gear)

Alternator

Gear

and

OIL

SYSTEM

FUEL

USED

1

SYSTEM

PART

REF.

NO.

2

9

/

NO.

120B648

122C360

QTY

GROUP

PART

DESCRIPTION

Intake,

Screen

Drain,

Oil

and

Oil

Filter

(Gasoline)

Pump - Includes

Pipe

Cup

REF.

NO.

PART

NO.

Delete

LINE,

FUEL

149A1228

503-708 Delete

5

QTY. USED

PUMP TO

CARBURETOR

.1

1

PART

DESCRIPTION

Standard Units

Units

with

Pulse

Pump - Optional

Type

Fuel

FUEL

SYSTEM

GROUP

(Gasoline) (Continued)

REF.

5 12 14 18

30

31

32

33

34

35

36

37

38

39

40 41

NO.

PART NO. QTY.

Delete Delete Delete Delete

149A136

526-63

800-4

149C1322

149A1321

503-301

149B1364

813-102

870-131

503-706

153A464

518-176

USED

1 2

2

1

2

1

1 1

PART

Cover, Fuel Washer,

Hole

Screw,

Cover

Pump

(See Separate

Cap,

Inlet - Optional

Clamp,

Optional

Bracket,

Mounting - Optional

Screw,

Pump

Optional

Nut,

Mounting (#10-32) - Optional

Line,

Tube - Optional

Bracket,

Clip,

DESCRIPTION

Pump

Flat - Copper - Fuel

Cover

Hex Cap -

Mounting (1/4-20

Fuel (Pulse

Pulse

Round Head - Pulse

Mounting (#10-32 x 5/8")

Hex -

Pulse - Fuel

Manual

Mounting

Type

Pulse

Manual

Opening

Fuel

Type) - Optional

Group for Components)

Fuel

Type

Choke - Optional

Fuel

Type

Pump to

Choke - Optional

In

Pump

x 5/8")

Pump Top

Pump Cap -

Fuel

Pump

Type

Fuel

Hole

Pump

Block

Pump

Fuel

-

Oil

Fill

V

FUEL

PUMP

PARTS

GROUP

(Pulse

Type) - OPTIONAL

EQUIPMENT

REF.

6

9

DELETE

NO.

1 2

3 4 5

7 8

PART

149B1322 142-537 142-540 149-1323 142-541 142-545

149-1326 149-1324 142-552 142-555

ENTIRE

NO.

FUEL

GROUP

"

PUMP

QTY. USED

J.

.1

'

1

PARTS

GROUP

1

1 1 1 1 1 1

v

(Mechanical

PART

Pump

h

:

•K> Screw,

Valve

Gasket, Gasket, Spring, Cover, Base, Plate, Diaphragm,

Type)

DESCRIPTION

Assembly, Complete

Plate

Pump

Base Cover

Pump

Assembly

Cover

to

Diaphragm

to

Valve

Diaphragm

Spring

Plate

1

,8

k

20

19

REF.

13

18

19 20

21

NO.

2 3 6 7

PART

NO,

Delete Delete

145A453 123A1241 821-10

140B1280

140A1282 809-59

870-106

-

'

y*-—2

AIR

CLEANER

QTY. USED

1 1 1

1

1 1

1

GROUP

PART

DESCRIPTION

Adapter, Carburetor Hose, Screw,

Adapter

Breather

Self

Locking - Air

Bracket Mounting

and

Mounting Elbow, Screw,

Bracket Mounting

Nut,

Mounting

Carburetor ^ Air Sheet

Tinnerman - Air

,3

Bracket,

Metal - Air

(1/4-20 x 1/2")

Air

Inlet

Cleaner

Air

Cleaner

Inlet

Cleaner

Cleaner Bracket

REF.

NO.

2

3

5 6

PART

NO.

150A96

150A1433

150A939 520A623

GOVERNOR

QTY. USED PART

GROUP

Stud,

Governor

Bracket,

Governor

Joint, Ball

Link,

DESCRIPTION

Speed

Throttle

Adjustment (Standard

Controlled

Speed

Controlled

Stud (Standard

Engines)

J

REF.

11

12 13 14 15 16 17

18 19 20 21 22

NO.

1 2

3 4 5

6

7

8

9

PART

NO.

134D2755 Delete 134B2752 Delete Delete Delete Delete Delete Delete Delete Delete Delete Delete Delete Delete SCREW,

SELF 821-10 821-10 821-10 Delete

134A2747 134A2761 134D2737 134B2763

BLOWER

QTY.

LOCKING

HOUSING

USED

1

4 5 2

1

1 1 1

GROUP

PART

Housing,

Backplate

•

Backplate Scroll

Housing

Backplate, Scroll,

Housing

Guard,

DESCRIPTION

Cylinder

Mounting (1/4-20

Air - Left

Air - Right

Mounting (1/4-20

Cover

(1/4-20

Scroll

Air

(Includes

Assembly - Air

Scroll

Side

x 1/2")

x 1 1/2")

Guard)

REF.

NO.

CHARGING ALTERNATOR

PART NO. QTY.

GROUP

USED

12

VOLT

PART

(OPTIONAL)

DESCRIPTION

19 20

134C2770

191B59

821-10

1

4

Flywheel

Ring Also

Flywheel Bracket, Regulator Mounting Screw,

Mounting

Assembly Gear and Magnet listed

Lock Head - Regulator Bracket

in the

Group

(Includes

Ring)

crankshaft

and

10

ONAN

INDUSTRIAL ENGINES

NHC

SERIES

TABLE

TITLE

PAGE

General Specifications 3 Dimensions and Clearances 4 Assembly Torques and Special Tools 6 Troubleshooting Chart . 7 Installation 8 Operation Service Fuel System 15 Governor System 20 Ignition Starting System . . . 26 Engine Disassembly 31 Parts Catalog 39 Engine

Information

11

and

Maintenance

and Battery Charging 23

Wiring

2

12

Diagram

57

OF CONTENTS

This

manual

structions

•

maintenance,

Since is the

shooting

Study

•

service

life

as well as

the first and

correct

chart

and follow the

and

better

How To Interpret MODEL and SPEC NO.

1..

Factory

2.

Specific

S -

MANUAL

contains

installation

information

adjustment

most

diagnosis

is

included.

instructions

maintenance

performance.

NHC - MS / 123 A

i 3 4

code

for

general

Type:

starting

GENERAL

and

operation

and

repair

important

of the

will

result

identification

required

part,

trouble, a trouble-

carefully. • Proper

for

of the.

of

repair

in

longer

purposes.

INFORMATION

in-

proper

engine.

work

engine

Onun warmnlH. to thf. original uaer, lhal ffach produrt of iln manufactu: is frcr. from rlefacls in material and factory workmanship if properly inslalleil.

serviced and operated under normal conditions according to Onan's

instrnctirm*. Onan

will,

under this warranly. repair or replace, as Onan may pari which on enaminatton nhail disclose to Onan's satisfaction to ha' been defective in material and workmanship; provided that such part shall he returned to Onan's .factory or one of its 'Authorized Service Sialions, transportalion charges prepaid, not later than one (I) year after the product is first placed in service. Such defective part will he repaired or replaced free of charpe, including lahor (in accordance wilh rales approved by Onan) during lltr staled one (I) year covorape under this warranty..'

TIIIS UAH RANTY ANO ONAN'S OHI.IC. ATION THKRKUNDRR IS IN LIEU OK ALL WARRANTIKS. KXI'HKSSKI) OH IMPUKO. INCLUOINC; WITHOUT LIMITATION,THK IMPLIKO WARRANTIKS OK M KRCII ANTA IM LITY AND K ITN ESS KOH A PARTICULAR PURPOSK. .\NO ALL OTIIKR OIH.ICATIONS OH LIAHIL1T1KS. INCI.UmNl.; LIAHILITY KOH INCIDKNTAI. AND CONSKQUKNTIAL DAMASK.

No person is aulborir.td lo give any olhi liabilily on Onon** of t (nan. and no |>ersnn atilhnrized to gi liuhililk-s on Ihe Seller's such Seller.

Qnan

MANUFACTURER'S

h.thalf

unless made

l^half

unless

WARRANTY

eler.l.

any

MS -

ELECTRIC

3.

Factory

4.

Specification

code

production

starting

for

optional

(Spec

Letter)

modification.

equipment

advances

supplied.

with

factory

ONAN

1*00 TIHO AVIMU

SPECIFICATIONS

NHC-MS/1

Number of Cylinders . '. ; • • • • .2 Displacement (cubic inch) 60

Cylinder Piston Stroke 3 inch

Horsepower . . . • • - • • • • -

Compression Ratio . - . - . - . ' - • • • - > , - 7.0 to 1

Ventilation

Oil

Oil Starting Ignition Combustion Air (cfm (? 3600 rpm) 80

Fuel Fuel

Bore

3-9/16

25

BHP @ 3600 rpm

Required (cfm (? 3600 rpm) 1080 Capacity . . 3-1/2 qt. Capacity

.' Gasoline (regular grade)

Pump . . . ; • • Diaphragm, 4 ft.

With

Filter

Change

. Electric

Battery

4

in.

qt-

lift

TUNE-UP

Spark Plug Gap .025 Breaker Point Gap .020" Ignition Tappets

NOTE:

Timing

(Cold) Intake -003 "

For

(Fixed), Electric Start Units . . . 25 0BTC

Exhaust ; -012"

gaseous

lash at .014". .

fuel

operation set spark plugs at .018" and

SPECIFICATIONS

ignition

timing

at 260BTC and

exhaust

valve

DIMENSIONS

Ail

clearances

All

dimensions

Valve

Tappet Intake Exhaust 0.012*

Valve

Stem

Valve

Stem,

Valve

Spring Length Free Compressed

Valve

Spring Tension (lb.) Open Closed

Valve

Seat

Intake

Valve

Seat Intake Exhaust

Valve

Stem Diameter Intake

Valve

Guide Diameter

Valve Lifter Valve Lifter

Valve

Seat

Valve

Face

Valve

Seat

Valve

Interference

Crankshaft

Camshaft Bear Camshaft Camshaft

Oil

Pump

Piston

to

90°

from

Piston

Pin in

Piston

Ring

Clearance

0.003

in

Guide — Intake

in

Guide — Exhaust

Length

. ... . . . . . . . . . . . . .

...............

. .

......................

Length

Bore Diameter

I

Diameter

. ....

.. . . . . .

........

(I.D.) Diameter Bore

Interference

Angle

Main

End Lift

Gear

Backlash

Cylinder, Strut Type (Measured below

pin)

Diameter

Piston

Groove

....

. . . .. . .

Width

. . . . . .

. . ... .

Angle

. .

Bearing

Clearance

. .

. . .

,

Width

AND

given

at

room temperature

in

inches

unless

. . . . . . .... . . . .

oil-controlling ring

CLEARANCES

of

70 oF.

otherwise

specified.

........

—

Minimum Maximum.

0.0025

71 79 38

1.5645

1.2510 1.2520

1.569

1.255

0.3425

0.3410

0.344

0.7575

0.7505 1/32

0.005

0.0015

0.003

1.3760

1.3740

0.0005 0.0023

0.002 0.016

0.002

0.002:

0.0015 0.0035

0.7500 Thumb

0.0001

0.0955 0.0965

0.0955

0.1880 0.1890

1.662

1.375

'

A.A

O

45°

JO

0.300

Push Fit

0.0025

0.004

42

1.5655

1.570

1.256

0.3430

0.3415

0.346

0.7480

0.7515 3/64

.0,0038

0.009

0.003 —

1.3770

1.3745

0.003

0.005

0.7502

0.0005

0.0965

Piston

Ring

Gap in

Piston

Ring

Side-Clearance (Top compression

Breaker

Spark Plug Gap - For Gasoline Fuel 0.025

Crankshaft Main Main Crankshaft Cylinder

*

Point Gap

Main

Bearing Diameter ..... . ••• 2.0015 2.0040

Bearing Clearance • • 0.0015 0.0043 .

Rod Bearing Journal - Standard Size 1.6252 1.6260

Bore - Standard Size . . . ' 3.5625 3.5635

Set exhaust valve at .014 for

Cylinder

(Full

Bearing Journal - Standard Size . .. 1.9992 2.0000

' •• 0.010 0.020

ring

only)

. 0.006

Separation) 0.020

gaseous

fuel

operation.

ASSEMBLY TORQUES

AND

SPECIAL TOOLS

TORQUES

Assembly torques as given

torque wrench. proper tightness without If

a torque wrench is not available, you

estimate the

nut or screw being installed and tighten accordingly. Be careful not to strip the

nuts and as

needed

TORQUE

Cylinder

Rear

Connecting

Flywheel Starter Mounting Bracket to

Gear Oil Other 3/8 Cylinder Intake Exhaust

screws

SPECIFICATIONS

Head Nuts

Bearing

Capscrew . . 35-40

Oil

Base

Case

Pump 7-9

Manifold

These

degree

to prevent them

Rod

Screws

Cover 8-10

of tightness

often

Plate

<^0^>

Bolt 27-29

43-48

Block

18-20

10-12

here

require the use of a

assembly torques

danger

with

of stripping the

necessary

threads.

the engine

from

working

Ft.-Lb.

Nuts 18-23

will

threads.

will

for the stud,

Check all

cold.

Tighten

loose.

assure

have

to

studs,

SPECIAL

These repair work; ' ^ * '' '''

Crankshaft Flywheel Combination

Main

Combination

Main Valve Valve Valve

Intake 420A309

.

{

Exhaust 420A310

Valve

Oil

Bearing

Gear Timing

TOOLS

tools are available

Gear

Pulling

Puller 420A100

Bearing Remover,

and Cam 420A325

Bearing Driver,

and Cam 420B324 Guide Seat Seat

Seat

Seal

Driver

Staker

Cutter -. 420A311

Guide and

Plate

Cover . 420B313

Advance Mech. Cover

420B181

Ring •. . 420A248

420A300

420A308

Driver

from

Onan to aid service and

Driver

..... 420A296

ENGINE

• •

•

TROUBLESHOOTING

STARTING SYSTEM

Loose or Corroded Battery Connection Low or Discharged Battery Faulty Starter Faulty Start Solenoid

• • • • • •

• • •

• •

• • • • • •

• • • •

f

• • •

• • • • •

a

• • • • • •

• • • •

• • •

• • • •

• • • • • •

• • • • • * • • •

* • • • •

• •

e

•

• •

•

t

•. •

•

• • • • •

•

Ignition Timing Wrong Wrong Spark Plug Gap Worn Points or Improper Gap Setting Bad Ignition Coil or Condenser Faulty Spark Plug Wires

FUEL SYSTEM

Out of Fuel - Check Lean Fuel Mixture - Readiust Rich Fuel Mixture or Choke Stuck Engine Flooded Poor Quality Fuel Dirty Carburetor Dirty Air Cleaner Dirty Fuel .Filter

Defective Fuel Pump

Wrong Valve Clearance

Broken Valve Spring

Valve or Valve Seal Leaking

Piston Rings Worn or Broken Wrong Bearing Clearance

COOLING

Poor Air Circulation

Dirty or Oily Cooling Fins

Blown Head Gasket

COOLING

Insufficient Coolant Faulty Thermostat Worn.

Water Pump or Pump Seal '

Water Passages Restricted

Defective Gaskets

Blown Head Gasket

SYSTEM

(AIR

(WATER

COOLED)

COOLEDI

• •

•

e

• • • • •

• •

• • • • •

• • • • • • • • • •

• • • • • • • • •

• • •

• •

•

Defective Oil Gauge Relief Valve Stuck Faulty Oil Pump Dirty Oil or Fi Iter Oil Too Light or Diluted

Oil Level Low

Oil Too Heavy Dirty Crankcase Breather Valve

THROTTLE AND GOVERNOR

Linkage Out of Adjustment Linkage Worn or Disconnected Governor Spring Sensitivity Too Great Linkage Binding

INSTALLATION

The type of installation can affect the

life

of the

engine, the cost of operation and the frequency of

necessary

to

ensure

Because variations of the engine,' are

typical

service. Plan the installation carefully

the

best

performance.

of the great variety of

these

uses,

and the many

installation instructions

or general in nature. Use the installation recommendations given as a general guide, improvising or altering as

necessary.

MOUNTING

There are several engine. Among factors to be considered are: location,

method of coupling the engine to the load, type of foundation

or support, etc. The engine should be mounted on a level surface if possible. Maximum operation angle is 15° sideways, 30° If

the engine is to

remark the oil level indicator to

acceptable

operate

methods of mounting the

front

to

rear

tilt.

at an angle, be

compensate

sure

for the

to

tilt.

VENTILATION

'

The engine must be provided

air

for cooling and for combustion.

Pressure

directly

Cooled Engine: Position the air inlet opening

in

front

of the engine and as close to the

engine blower wheel as possible. The

inlet

should be not louvers or compensate

ventilation

grill

for the reduced air

if the driven load

work

less

are

operation.

with

than

used,

a supply of fresh

area

80square

increase

flow.

generates

inches. If

the

Provide extra

heat

of the

area

to

during

vibration. bustible

sweeping type (long radius) elbows. size feet in length. Locate the outlet away

Shield the line if it

wall

or partition. If turns are

(from

manifold outlet size) for

passes

Increase

each

through a com necessary,

use

one pipe

additional ten

from

the air

intake.

CARBURETOR

Proper engine efficiency

AIR

INTAKE

depends

upon a supply of fresh air to the carburetor. Under special conditions, it

may be engine, using a longer connection For extremely dusty or special heavy duty air

FUEL

The engine

fuel a 1/4" inverted flare tube is

used, flexible pipe thread end is

from

The convenient location. If the tank is installed

necessary

to move the air

hose

dirty

conditions, install a

cleaner

as

cleaner.

SYSTEM

uses

a diaphragm type

pump has a 1/8" pipe thread inlet,

fitting.

form

a loop in the

fuel

hose,

to

used,

the

fuel

pump inlet.

fuel

supply tank may be installed in any

line,

absorb

vibration. If a line

remove the flare type

fuel

If a

solid

or install .a section of

off the

necessary.

pump. The

fitted

with

wall

line

with

a

fitting

safe,

within

the engine enclosure, provide a vent line to the outside

of

the enclosure.

The installation' of a and the should be easily

fuel

pump is recommended. The

fitted

accessible

fuel

filter

between the

fuel

with

a shutoff valve and should be

for cleaning.

fuel

tank

filter

The

heated

escape

air.

A duct between the compartment air inlet and the engine blower housing may be air

outlet opposite the intake or at

The

area than that of the inlet. to

permit

air outlet must allow the

freely and prevent recirculation

necessary.

least

of the outlet should be at

Allow

sufficient room on all

access

for servicing.

heated

with

air to

the cooling

Locate the

at a 90° angle.

least

15% larger

sides

Open Air Installation: For installations where the engine is operated outside, ventilation problem.

However, in protecting the engine

elements, see that nothing obstructs the

will

from

flow

be no

the

of air

around the engine.

EXHAUST

Pipe POISONOUS Use a length of exhaust

outlet and any

exhaust

flexible

rigid

gas outside enclosure.

tubing between the engine

piping to

absorb

engine

CONNECTING

The dimensions of various power takeoff as

follows:

SHAFT

STD

Rockford Gear

Reduction

Belt

Drive:

TO THE

Clutch

LOAD

DIAMETER

1-7/16 1-7/16

1-1/4

V-belts are preferable to

LENGTH

3-1/16 3-1/16 2-3/4

flat

shafts

KEY

are

SIZE

3/8 3/8

1/4

belts. Consult a reliable belting supplier for recommendations regarding

size

of pulleys, number of belts, etc. required. A

typical

belt drive installation is shown in Figure 1.

KEEP SHAFTS

AND LOAD PARALLEL

KEEP PULLEYS ALIGNED

BELT

z

IN

POSITION - PULLING

ENGINE

PULLEY

BELT

Comply

1.

The shafts of the engine and the load must be

parallel

2.

The pulleys of the engine and the load must be

in

3.

Mount

TIGHTENED ADLER PULLEY

LOAD

IN POSITION PULLING LOAD-

FIGURE

with

the

with

alignment.

the engine pulleys as close to the engine

WITH EACH OTHER

LOOSENED

- NOT

.!.

DRIVE BELT INSTALLATION

following

each other.

OF

ENGINE

BRACKET BELT

installation

TO

OFF

PULLEY

KEEP

ENGINE

requirements:

as possible.

4.

If the

installation

permits, belts should run

hori-

zontally.

5. Some method of disconnecting the load for starting is

recommended. If a

tightener

Flexible load

centered

Coupling:

drive

is used, the load shaft must be in

with

idler

arrangement can be used.

If a

the engine shaft (Figure 2).

clutch

flexible

is not used, a belt-

coupling

engine-td-

line

and

Reduction mounted of

connecting the load is the

directly

Clutch at the factory or in the

ing

to the

Provide the wet holes set screw. install

Drill for

the

from

Gear

Drive:

Reduction

gear

drives are

at the factory (when ordered). The method

same

as when connecting

to the engine shaft.

Installation: A Rockford

field.

following

room

Apply

screw

flush

instructions and Figure 3.

for the

clutch

with

a 3/8-16 x 1/2" slotted

sealing compound to the threads and

with

the

a 13/64".hole (or

clutch

the end and

set screw. Locate, center of hole 11/32"

directly

Clutch

Install

adapter casting by

can be installed

the

clutch

accord-

plugging

headless

cylinder

filed

block.

slot)

in the crankshaft

opposite the keyway in the

crankshaft.

Install

the

clutch

using

two cap screws 3/8-16 x 2" on the one cap screw 3/8-16 x 1-3/4"on the upper #2 side

(cylinder

stud

through the adapter

remaining

hole. Use a

screw. Use a

stud

nut.

Install

the crankshaft key. Remove the

screw.

Install

the crankshaft,

hammer

until

adapter,

nearer

flat

washer and a

the

clutch

driving

with

drain

slot downward,

clutch).

lock

Install

into

the 3/8 x 3-7/8"

the engine

washer on each assembly

lock

washer under the

assembly (less housing) to

it on

carefully

with

set screw hole is aligned.

lower

cylinder

block

clutch

a.

soft-faced

Install

and

upper

set

set screw to bottom in crankshaft hole, then back it out one

full

turn.

Tighten

clutch

is clamped securely to crankshaft.

clutch

retaining screws

Lock

until

the

screws and tighten the set screw.

ENGINE POWER

TAKE

- OFF

SHAFT

FIGURE

2.

FLEXIBLE COUPLING

FLEXIBLE

COUPLING

KEYWAY

i

DRILL 13/64" HOLE"-^

CRANKSHAFT STUB SHAFT

A867 CLUTCH?^

ADAPTER

FIGURE

1/8" DEEP

CLUTCH CLUTCH

ASSEMBLY

SET

3.

CLUTCH INSTALLATION

H0US

SCREW

!N<L

•I

1/32"

TAKE-OFF

SHAFT

Apply

grease

the clutch throw-out to align the

to splined power takeoff shaft. Position

grease

fitting

with the hole in the housing (#1 cylinder side, horizontal). Pull

the throw-out collar outward to remove tension.

Install

the clutch housing so that the clutch throw-out

fork

engages

shaft is properly

two

cap

screw

7/16-14 x 1-3/4"on Install grease

the throw-out collar. Be

meshed

screws

the stud fittings just

7/16-14

washer

until

sure

the

serrated

with

the clutch plate. Use

x 2"on the lower and one cap

the

upper

#2 cylinder side.

and nut. Lubricate the two

grease

appears.

BATTERY

POSITIVE.

CABLE

BATTERY CONNECTIONS (Engines with Automotive

Type Separate Starter)

Connect the 12 start

switch terminal. Connect the battery negative

cable

to the ground point on the

volt

battery positive

cable

engine

oil

to the

base

engine

(Figure

4).

FIGURE

BATTERY NEGATIVE

(FASTEN UNDER CONVENIENT

4.

BATTERY CONNECTIONS

BOLT

CABLE

ON

ENGINE)

.

10

OPERATION

BEFORE

Crankcase Oil: Be with Use a good

Petroleum

use an oil designated SE and the oil manufacturer certifies it

perform

Recommended Fuel: Use clean, fresh, regular grade,

automotive types.

For

obtained

engines that have - previously used leaded gasoline, heads

from

to nonleaded gasoline, preignition could occur causing severe damage

Never

some

fuel assure

STARTING

1.

2.

If

the engine oil Remove the plugs, clean in suitable solvent, dry

thoroughly engine is

inhibitor

STARTING

1.

2.

APPLYING

When

engine, it should be applied-gradually in about

steps; time.

BATTERY

The

STARTING

sure

the crankcase has been

oil to the

satisfactorily in gasoline engines.

new engines, the most satisfactory results are

must, be taken off and all lead deposits removed

engine before

CAUTION

fill

space*

line

fuel

Move Push the

used at the factory may have

Close the choke about three quarters of the way or

.

as

necessary

Pull

the engine. Do not

"FULL" quality

Institute) designation SE or SE/CC. Do not

with

the designation CD

gasoline. Do not use

by using nonleaded gasoline. For older

If lead deposits

. engine before switching from leaded

to the

the tank when the engine is

in the tank for

valve (when used) and operate primer to

supply.

(Electric

-the

ignition

START

fails

and

install.

first

started is normal and is

oil.

(Manual

the start rope

mark on the oil

oil

with

switching

engine.

fuel

the API

highly

to nonleaded gasoline.

are not

level

unless

leaded premium

removed from

running.

expansion. Open the

Start)

switch

button to crank the engine.

to start at

Heavy exhaust smoke when the

.to its ON

first

attempt,

fouled

the spark plugs.

Start)

according to temperature conditions.

with.a

jerk.

fast steady

pull

filled

indicator.

(American

it is also

will

Leave

position;

inhibitor

caused

by

to crank

LOAD

applying

each

Start

the load -to a new or reconditioned

step

of not

with

1/4.load, then 1/2, 3/4 and

less

than 30 minutes running

full

four

load.

CHARGING

battery charge rate is

controlled

by a charge

regulator.

rate of charge at operating

STOPPING

Disconnect.all equipped

tion'switch

HIGH

1.

2.

LOW

1.

2.

3. Keep

4.

DUST

1.

2.

3. Change crankcase oil and

4.

5. Keep governor linkage clean.

OUT-OF-SERVICE

Protect an engine that

than

1.

Run

2.

3.

4.

5. Service air cleaner.

6. Clean governor linkage and protect by wrapping

7.

•8.

9. Provide a suitable cover for the entire

10.

The regulator is set to

speed.

THE

ENGINE

load before stopping the engine. Engines

with

battery

to the OFF

ignition

position.

are stopped by the

.

allow

the proper

igni-

TEMPERATURES

See that nothing obstructs air • flow

the engine.

Keep

cooling

properly

fins

clean. Air housing should be

installed and undamaged.

to and

from

TEMPERATURES

Use correct SAE No. oil for temperature conditions.

Change oil

Use fresh

sation.

charged

Partially

avoid

AND

Keep Service air cleaner as frequently as required.

recommended under normal conditions.

Keep oil and gasoline in dust

only

when engine is

fuel.

Protect against moisture conden-

fuel

system clean and batteries in a

condition.

restrict

overheating.

cool

air

warm.

flow,

DIRT

unit

clean. Keep

cooling

filter

tight

well

but use

system clean.

more

care

often

than

containers.

PROTECTION

will

be out-of-service for more

30 days as

unit Turn Drain

and

attach a

Remove each spark

tablespoons) of rust

into

each cylinder. Crank engine

•

several times.

with

Plug exhaust outlet to prevent entrance of mois-

ture,

Wipe

film

of

If battery is used, disconnect and

battery

follows:

until

thoroughly

off

fuel

supply and run

oil

from

oil

base

warning

Install

a clean

dirt,

entire

cloth.

bugs, etc.

unit.

Coat rustable parts

grease

storage procedure.

or oil.

warm.

until

unit

stops.

while

tag stating oil viscosity used.

plug.

inhibitor

spark

still

warm.

Pour one ounce (two

(or SAE #50 oil)

slowly

plug.

follow,

Refill

(by hand)

with a light

unit.

standard

to

11

SERVICE

AND

MAINTENANCE

SERVICE

Inspect Check Check Clean Change Check Check Clean Check Replace Replace Remove Check Inspect Complete

x* xl

Engine

Fuel

Generally

Supply

Oil Level

Governor

Linkage

Crankcase

Breaker

Battery

Fuel

Spark

Points

Electrolyte

Filter

Plugs Oil Filter Air

Cleaner

Deposits

Valve

Clearance

Valves,

Grind if

Reconditioning

- Perform more often under dusty or extreme

- Recommended

THESE ITEMS

Oil

Level

in

Combustion

Necessary

interval

Chamber

cold

weather conditions.

in hot weatner or heavily loaded natural gas and propane operation.

PERIODIC MAINTENANCE SCHEDULE

Regularly operating

scheduled maintenance is the key to lower

costs

and longer service

life

for the

unit. The above schedule can be used as a guide. However, actual operating conditions under should

be the' determining factor in establishing a

which a unit

is run

maintenance schedule. When operating in very dusty or dirty

have to be reduced. Check the

case

conditions,

oil, the

filters,

some

of the service periods may

condition

etc. frequently

of the crank-

until

the proper service time periods can be established. When any abnormalities

engine or —

contact your Onan dealer.

occur in operation — unusual

accessories,

loss of power, overheating, etc.

noises

from

AFTER

8

X X X

NOTE: available, or MS/DM which facturer's Sequence Tests

Don't

When brand

EACH

CYCLE

OF INDICA1

FED

HOI

50 ] 100 200 500 1000

X*

xl

// of/s

use oil

use an oil

adding oil between

X* X X X X

X* X*

X X

with these designations

with

has

with

the API

passed

the API

changes,

designation

all the

and the

designation

Automotive Manu-

MIL-L-2104B Tests.

always use the

X

are not yet

MS,

DS.

and weight that is in the crankcase. Various

brands of oil may not be compatible when

together.

CAP

ANO OIL

LEVEL INDICATOR

JRS

5000

X

MS/DG

same

mixed

CRANKCASE OIL

The oil capacity is 3-1/2 U.S. quarts (4 Fill

to the

Use a good

(American SE/CC. Do not use an oil unless certifies engines.

determining

IMPORTANT:

by weight with natural

"FULL"

quality,

mark on the oil

detergent oil

level with

Petroleum Institute) designation SE or

with

the designation CD

it is also designated SE and the oil manufacturer

it

will

perform satisfactorily in gasoline

Ambient

temperatures must be the factor for

the proper SAE oil weight.

Use low ash

content oils .03:85 percent

gas or

propane fueled engines.

with

filter).

indicator.

the API

12

KEEP

AT THIS LEVEL.

NEVER OPERATE

ENGINE WITH

BELOW THIS LEVEL.

OIL

FIGURE

OIL

5. OIL

-FULL

-LOW

ALWAYS REPLACE

A874

LEVEL INDICATOR

CAP TIGHTLY, OIL LEAKAGE OCCUR.

OR

MAY

Oil

consumption may be higher

than

with

a single grade oil if both

with

a multigrade oil

oils

have comparable viscosities at 210 0F. Therefore, single grade oils

are generally more desirable, unless anticipating

a

wide

range ot temperatures. Use the proper grade oil

for

the expected conditions.

GRADE

5W

10W 30 50

Check oil

TEMPERATURE

Below

0° 0oto 30° 30°

to 90°

90

daily.

0

Change oil every 100 hours

Above

level under normal operating conditions. When operating in extremely

dusty or

dirty

conditions, change oil more

often.

Change the crankcase oil the

filter

by

turning wrench. air dry

gasket on

Install

oil indicator

the

Add the strip provided

loss in the

the

drip

the

becomes so

area

pan located below the

filter

with a film

filter

finger-tight

dirty

cannot be

filter

service period.

filter

every 200 hours. Remove

counterclockwise, using a

with

the

filter

to prevent

indicated. It is advisable to

filter.

of oil before

Coat rubber

installing.

plus 1/4 to 1/2

that the markings on the oil

seen,

change the

filter

and shorten

filter

wipe

turn.

level

If

BREATHER

HOSE

CLAMP

CAP ANO

VALVE

—

BREATHER TUBE

FIGURE

7..

CRANKCASE

BREATHER

AIR CLEANER.

The

NHC engine

cleaner. Remove and replace every 200hours.

uses

a replaceable, spin-on air

HOSE

DRIP

OIL

FILTER

PAN

CAUTION"!

Do

not. run

removed.

engine with

air

cleaner

FIGURE

6. OIL

FILTER

LOCATION

13

FIGURE

8. AIR

CLEANER

Use only SAE50 motor oil or SAE90 mineral

Do

not use lubricants commonly .known as extreme

pressure

lubricants, hypoide lubricants, etc.-

gear

oil.

KEEP

GOVERNOR

LINKAGE

LUBRICATED

FIGURE

9.

GOVERNOR LINKAGE

Maintain

filling

the proper oil level between

will

cause

foaming,

which

can lead to an oil leak due to overheating. Remove the of

the

case

and the oil level plug

gear

case.

flow

from

pint

U.S.

VENT PLUG

Fill

the oil level plug hole.

measure.

the

Replace

case

until

both plugs. See Figure 10.

from

the oil just begins to

Gear

changes.

filler

.Over-

plug.on top

the face of the;

box holds 1/2

REDUCTION

Drain

the

and

refill

grade.

Repeat

GEAR

gear

with

DRIVE

box after the

fresh lubricant of the recommended

this procedure every six months there-

after, or every lOOhours.

first

lOOhours of operation

REMOVE PLUG.

FILL WITH LEVEL

OIL TO

OF

FIGURE

HOLE

10.

REDUCTION GEAR DRIVE

14

FUEL SYSTEM

GASOLINE

For

correction of problems traced to the gasoline carburetor, use the appropriate procedures selected from

the

and 13.

Adjustment follows

1.

Make

2.

Start the engine and

3.

With

4.

Apply a full

Adjustment cannot be applied, adjust the carburetor as

1.

Perform

-Under

STOP

CARBURETOR

following

Under Load:

when a

sure

and that the governor is adjusted.

carburetor is so far out of adjustment that the engine

will

gently

to their

turns,

first

no load applied to engine, ment out below

normal. Then

engine

speed

turn

the main adjustment in slightly the engine

below normal.

Under "No Load" Conditions: When a load

steps

Load.

THROTTLE

SCREW

sequence,

full

load can be applied.

the

ignition

not start, close both needle valves

seats.

the

idle

until

the engine

returns to normal.

load to the engine and then carefully

speed

returns to normal.

1 and 2 as given under Adjustment

referring to Figures 11

Adjust

system is

allow

Then open each 1 to 1-1/2

and then the main adjustment.

turn

Turn

the carburetor as

working

it to warm up. If the

turn

the

speed

the needle in

until

FUEL

drops

the

the needle out

IDLE

properly

idle

adjust-

slightly

until

speed

follows:

drops

until

ADJUSTMENT

r

A

the

2.

Pull

out on the governor mechanism to slow the

unit

down to about 400-500 rpm.

.3.

Set the

(so the engine is

running

4.

Release

engine to accelerate. If the engine evenly correct. If not, adjust the needle outward about

1/4 release accelerates

releasing the governor.

5.

With

throttle-

Float-Level provide

and check the

1.

Remove the

linkage

2.

Remove the two carburetor mounting nuts and

remove the carburetor.

3. Unscrew the main

4.

Invert

surface the gasket. Bend the

duce this spacing.

NOTE: spring loaded fuel inlet valve, should the

in

5.

Reassemble,

6. See Figure 12.

idle

adjustment screw for even operation

firing

smoothly).

the governor mechanism to

and

without

turn

and again slow down the engine and

the mechanism. Continue

evenly and

the carburetor and governor adjusted, set the

stop screw at the desired

Check: If the carburetor adjustment

satisfactory operation, remove the carburetor

float

level

fuel

line,

and choke wires.

float

b.owl

fuel

adjustment assembly

the carburetor and check that the

nearest

// the

be 1/8 ± 1/16

full weight

the

needle.

the gasket is 1/8 ± 1/16

carburetor utilizes

of the

install

on both cylinders and is

allow

accelerates

a lag, the main adjustment is

until

the engine

without

as

follows:

air cleaner

nut and remove the entire

flpat

inch from

float compressing

and test.

a time lag after

idle

speed.

fails

hose,

from

tab as required to pro-

an

the

governor

the

float

bowl. float

inch

from

internally

float surface

gasket with

the

spring

the

to

FIGURE

II.

CARBURETOR

FLOAT

-MAIN

BOWL

FUEL

ADJUSTMENT

B

ADJUSTMENTS

NUT

15

•

GASKET

DIMENSION

A9I3-1

FIGURE

12.

T.O

FLOAT

1/8

INCH

LEVEL

BEND

TO

TAB

ADJUST

ADJUSTMENT