Toro 30620, 30798, 31-16O803, 31-16O804, 41-20OE02 Service Manual

ONAN TORO POWER PLUS P216, 18, 20, 24 ENGINES - HORIZONTAL

Table of Contents – Page 1 of 2

SAFETY PRECAUT I O NS

GENERAL PROTECT AGAINST MOVING PARTS BATTERIES FUEL SYSTEM EXHAUST SYSTEM EXHAUST GAS IS DEADLY! COOLING SYSTEM KEEP THE UNIT AND SURROUNDING AREA CLEAN

CAUTION

GENERAL INFORMATION INTRODUCTION ENGINE MODEL REFERENCE

SPECIFICATIONS

DIMENSIONS AND CLEARANCES P216, P218, P220 P216,P218,P220 P224 P224

ASSEMBLY TORQUES SPECIAL TOOLS ENGINE TROUBLESHOOTING

OIL SYSTEM CRANKCASE OIL OIL FILTER CHANGE CRANKCASE BREAT HER CRANKCASE BREAT HER SE RVICE P216, P218, P220 P224 PRESSURE LUBRICAT IO N OIL PUMP OIL BYPASS VALVE

FUEL SYSTEM CARBURETOR CARBURETOR SPEED SETTINGS CARBURETOR OVERHAUL REMOVAL DISASSEMBLY CLEANING AND REPAIR REASSEMBLY AN D INSTALLATION PULSATING-DIAPHRAGM FUEL PUMP FUEL PUMP TEST PROCEDURE PURPOSE CARBURETOR (BEGINNING SPEC G) CARBURETOR HIGH-ALTITUDE JET (OPTIONAL) AIR CLEANER GOVERNOR SENSITIVIT Y

ONAN TORO POWER PLUS P216, 18, 20, 24 ENGINES - HORIZONTAL

Table of Contents – Page 2 of 2

IGNITION AND BATTERY CHARGING IGNITION SYSTEM DESCRIPTION IGNITION TIMING CONTINUITY TEST IGNITION COIL SPARK PLUGS BATTERY INSPECTION BATTERY JUMP STARTING FLYWHEEL ALTERNAT OR ALTERNATOR OUTPUT TEST TYPICAL WIRING DIAGRAM

STARTING SYSYTEM ELECTRIC STARTER SERVICE STARTER REMOVAL STARTER DISASSEMBLY STARTER ASSEMBLY INSPECTION AND TESTING STARTER MOUNTING

ENGINE DISASSEMBLY DISASSEMBLY/ASSEMBLY SUGGESTED DISASSEMBLY ORDER SUGGESTED ASSEMBLY PROCEDURE OPERATION TESTING COMPRESSION TAPPET ADJUSTMENT VALVE SYSTEM INSPECTION TAPPETS VALVE FACE AND SEAT GRINDING FLYWHEEL GEAR COVER GOVERNOR CUP TIMING GEARS PISTONS AND CONNECTING RODS CYLINDER BLOCK CLEANING INSPECTION REBORING THE CYLINDER HONING CYLINDERS (USING PRECISION HONES) DEGLAZING CYLINDER BORE S CRANKSHAFT BEARINGS CRANKSHAFT ENDPLAY CHECKING CONNECTING ROD BEARING CLEARANCE WITH PLASTIGAUGE OIL SEALS PISTON ASSEMBLY INSTALLATION OF PISTON IN CYLINDER CYLINDER HEADS P216, P218, P220 INSTALLATION 224 INSTALLATION

Service

Manual

P216,18,20,24

TORO

Engine

Power

Plus

1709

Tractors & Riding Mowers

Safety

It

is recommended that you read your engine manual and

become thoroughly acquainted with your equipment before

you start the engine.

severe personal injury or death.

severe

personal injury or death.

Precautions

This symbol if used warns of imme-

diate hazards which will result in

This symbol refers to a hazard or unsafe practice which can result In

Fuel System

DO

NOT

fill

fuel tanks while engine

DO

NOT

smoke

or

use an open flame in the vicinity

or

fuel

tank.

engine highly flammable.

Fuel lines must be and free from leaks. Piping at the engine should be approved flexible line., flexible lines as copper brittle enough

Internal combustion engine fuels are

of

steel piping, adequately secured,

Do

will

to

break.

is

not use copper piping for

work harden and become

running.

of

the

This symbol refers to unsafe practice which can

personal injury or product or property damage.

Fuels, electrical equipment batteries, exhaust gases and moving parts present potential hazards that serious, personal injury. Take care mended procedures. All local. state and federal codes should be consulted and complied with.

This engine is not designed

tended for

Use

of

this engine in aircraft can result in engine failure

and causes serious personal injury

General

Provide appropriate fire extinguishers and install them in

convenient locations. Use an extinguisher rated

NFPA.

Make sure that all fasteners accurately torqued. Keep guards in position over fans, driving belts, etc.

If

it is necessary running, use extreme caution when close moving parts. etc.

Protect Against Moving Parts

Do

not wear loose clothing such as PTO shafts, flywheels, blowers, couplings, fans, belts, etc.

to

make adjustments while the engine is

in

following these recom-

use

in

any type of aircraft.

on

the engine are secure and

in

the vicinity of moving parts.

or

death.

to

a

hazard

can

hot exhausts,

result

result in

or

In-

ABC

or

in

by

Be sure all fuel supplies have a positive shutoff valve.

Exhaust

Exhaust gases contain carbon monoxide, a poisonous gas that can cause unconsciousness and death. and colorless gas formed during combustion

fuels.

If

you experience any immediately, shut down the unit and do not use until it has been inspected.

The best protection against carbon monoxide inhalation is proper installation and regular, frequent inspections complete exhaust system.

or

immediately and have competent mechanic.

System

Exhaust products toxic and can cause injury, applications, especially those within a confined area, should be equipped with an exhaust system

to

gases

Do

Make' sure that your exhaust system Ensure that exhaust manifolds are secure and are

warped by

Symptoms

Dizziness Headache Weakness and Sleepiness

appearance

the outside atmosphere.

not

use exhaust gases

Gas

is

of

any internal combustion engine are

or

death

if

inhaled.

to

heat a compartment

is

free

bolts

unevenly torqued.

Deadly!

It

is an odorless

of

carbon monoxide poisoning are:

Vomiting Muscular Twitching Throbbing in Temples

of

these symptoms. get out into fresh air

If

you notice a change in the sound

of

exhaust system, shut the unit down

it

inspected and repaired at once by a

of

to

hydrocarbon

All

engine

discharge

of

leaks.

not

of

the

Keep your hands away from moving parts.

Batteries

on

Before starting work

to

prevent inadvertent starting

DO

NOT

SMOKE

batteries give can be ignited by flame, electrical arcing

Verify battery polarity before connecting battery cables. Connect negative cable last.

off

the engine. disconnect batteries

of

the engine.

while servicing batteries. Lead acid

a highly explosive hydrogen gas which

or

by smoking.

Cooling

Keep

System

Coolants under pressure have a higher boiling point than water., DO NOT open a radiator pressure cap when coolant temperature is above engine is running.

the

Unit and Surrounding Area Clean

Make sure that oily rags are not left

Remove all unnecessary grease and Accumulated grease and oil can cause overheating and subsequent engine damage and present a potential fire hazard.

212ºF

on or

(100ºC)

near the engine,

oil

or

from the unit

while

~-

E-6

Table

of

Contents

TITLE

General

Specifications Dimensions and Clearances

Assembly

Engine Troubleshooting Oil Fuel

Ignition

Engine

Starting

Englne

Information

Torques and Special Tools

System

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

and

Battery

Wiring

System.

Disassembly...

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

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

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

Charging

Diagram

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

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

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

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

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

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

PAGE

.1-1

.2-1

.3-1

.4-1

.5-1

.6-1

.7-1 .8-1

.8-7

.9-1

10-1

EXHAUST GAS

Exhaust gases gas) contain is poisonous and can cause unconsciousness and monoxide poisoning can include:

Dizziness Nausea Headache

Weakness and Sleepiness

IF

YOU OR ANYONE ELSE EXPERIENCE, ANY OF THESE SYMPTOMS, GET OUT

INTO THE FRESH AIR lMMEDlATELY. attention. Shut down the unit and do not operate until repaired.

Protection against carbon monoxide inhalation includes proper installation,

ventilation and regular, frequent visual and audible inspections

exhaust system.

from

carbon

all fuels (Including diesel, gasoline, liquid

monoxide, an odorless and colorless

IS

DEADLY!

gas.

death.

Throbbing in Temples

Muscular Twitching

vomiting

Inability

If

symptoms persist,

Symptoms of

to

Think Coherently

it

has been inspected and

propane,

Carbon

seek

of

the complete

natural

monoxide

carbon

medical

General

Information

This manual deals with specific mechanical and electrical information needed by engine mechanics for

or

troubleshooting, servicing, repairing, engine.

Use

the separate PARTS MANUAL for parts identification and for establishing their proper location on assemblies. The PARTS MANUAL contains detailed exploded views of each assembly and the individual piece part numbers and their proper names for ordering replacement parts.

The illustrations and procedures presented in each section apply to the engines listed on the cover. flywheel-blower end of right and left sides are determined by viewing the engine from the front. The No. cylinder is on the right.

If

a major repair

-mechanic should either do the job check the ensure that all dimensions, clearances and torque

values are within the specified tolerances.

or

work

of the mechanic assigned to the job to

the

engine is the front end

1

cylinder is on the left, No.

an overhaul is necessary, a competent

overhauling the

or

supervise and

The

so

2

Use only Genuine ensure quality results. When ordering parts, model and shown

on

the nameplate.

Tom

and

the best

spec

number as well

Plower Plus

possible

always

as

replacement

repair and overhaul

use the complete

the

serial

parts to

number

ENGINE MODEL REFERENCE

Identify your model by referring to the model and

(spec

specification plate. Always use these numbers and the engine serial number when making reference

How to interpret

letter) as shown on the unit name-

to

your engine.

MODEL

3

and

SPEC

NO.

6

7

Use

the table of contents for a quick reference to the

separate engine system sections. The troubleshooting guide is provided as a quick

reference for The wiring diagram shows how the electrical compo-

nents are interconnected. The disassembly section contains major overhaul

procedures for step by step removal, disassembly, inspection, repair, and assembly of the engine components.

locating

See

the Operator's Manual

and

correcting

INCORRECT SERVICE SEVERE PERSONAL INJURY AND/OR EQUIPMENT DAMAGE. SERVICE PERSONNEL MECHANICAL SERVICE.

engine trouble.

for

fuel and oil recommendations and

OR

REPLACEMENT OF PARTS CAN RESULT IN

MUST

BE QUALIFIED

1.

Factory code for general identification of basic engine series.

2.

Number

3.

BHP rating.

4.

Fuel required

5.

Engine duty cycle.

6.

Factory code for designated optional equipment,

any.

7.

Specification factory production modifications.

TO

PERFORM ELECTRICAL AND/OR

of

cylinders.

(G

=

gasoline).

(spec

letter) which advances with

the

Periodic Maintenance Schedule.

if

1-1

Specifications

This manual contains

SI

metric equivalents that follow immediately

after the

U.S.

customary units of measure.

in

parentheses

2-

1

Dimensions

and

Clearances

P216. P218. P220

All

clearances given at room temperature of

in parentheses) unless otherwise specified

DESCRIPTION

CYLINDER BLOCK

Cylinder Bore Honed Diameter Maximum Allowable

Taper

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

Out-of-Round Main Bearing Inside Diameter (Without bearing) Main Bearing Inside Diameter (Installed service bearing) Camshaft Bearing

CRANKSHAFT

Main Bearing Journal Diameter Main Bearing Clearance Connecting Crankshaft End Play

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

Bore

(Installed service bearing)

Rod

Journal Diameter

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

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

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

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

70°F

.

(21 °C) . All dimensions in inches (approximate millimeter dimensions

.

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

...........

.....

3.2490 (82.52)

2.1870

2.001

5

1.3757

1.9992

0.0024

1.6252

0.0060

(55.55)

(50.84)

(34.94)

(50.78) (0.061) (41.28) (0.1 52)

3.2500 (82.55)

0.005

0.003

2.1

880

2.0040

1.3787

2.0000

0.0042

1.6260

0.01

20

(0.1 3)

(0.08)

(55.58)

(50.90)

(35.02)

(50.80)

(0.1

07)

(41

30)

(0.305)

CONNECTING

Large Bore Diameter

Connecting

Piston Pin Bushing Bearing to Crankshaft Clearance

CAMSHAFT

Bearing Journal Diameter Bearing Clearance End Play Lobe Height

P216. P218 Intake P216. P218 Exhaust

P220

Intake

P220 Exhaust

PISTON

Clearance

Measure Piston Pin Bore Ring Groove Width

Top

Compression Ring Middle Compression Ring Bottom Oil Control Ring

ROD

(Rod

bolts

properly torqued)

Rod

Side Clearance

Bore

(Finished bore)

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

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

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

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

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

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

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

in

Cylinder

90°

to pin 1.187 inch

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

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

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

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

...........

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

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

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

below

top

of

piston

.........

1.6280

0.0020

0.6879

0.0020

1.3740

0.001 5

0.01 10 (0.279)

0.0033

0.6877 (1 7.47)

0.0800

0.1 880

(41.35) (0.051) (1 7.47) (0.051)

(34.90)

(0.038)

1.1

370

1.1 570

1.1

670

1.1

570

(0.084)

(2.032) (2.032) (4.775)

1.6285 (41

0.0160

0.6882

0.0033

1.3745

0.0030

0.0480

(28.88)

(29.39)

(29.64)

(29.39)

0.0053

0.6882

0

0.081

0

0.081

0.1 890

36)

(0.406)

(1 7.48)

(0.084)

(34.91) (0.076) (1.219)

35)

(0.1 (1 7.48)

(2.057) (2.057) (4.800)

3-1

P216. P218. P220

PISTON PIN

Clearance in Piston Clearance in Connecting

Diameter

PISTON RINGS

Clearance

Top Groove

Ring End Gap in Cylinder

INTAKE VALVE

Stem Diameter Clearance (Stem to Guide)

Valve Face Angle

INTAKE VALVE SEAT

Seat Bore Diameter Seat Outside Diameter Valve Seat Width Valve

EXHAUST

Stem

Clearance (Stem to Guide)

Valve

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

seat

Angle

VALVE

Diameter

Face

Angle

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

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

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

in

Block

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

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

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

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

Rod

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

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

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

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

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

MINIMUM

Inches

0.00004

0.0002

0.6875

0.0030

0.01 00

0.2795

0

0.001

1.4395

1.4700

0

0.031

0.2780

0.0020

MAXIMUM

(mm)

(0.001) (0.005) (1 7.46)

(0.076) (0.254)

(7.099

(0.025) 0.0025

(36.56)

(37.34) (0.787)

(7.061) 02785 (0.051)

Inches

0.00064

0.0007

0.6877

0.0080

0.0200

02800

44º

1.4405

1.471

0.0470

45º

0.0035

44º

0

(mm)

(0.016) (0.01 8) (1 7.47)

(0.203)

(0.508)

(36.59) (37.36)

94)

(1.1

EXHAUST VALVE

Seat

Bore Diameter in Seat Outside Diameter Valve Seat Valve Seat Angle

VALVE

Intake Inside Diameter Exhaust Inside Diameter

TAPPET

Body Diameter Bore Diameter

Clearance in Bore

VALVE SPRINGS INTAKE AND EXHAUST

Valve Spring Valve Spring Length

Valve Open Valve Closed

Spring Load (Valve Open Length)

Spring Load (Valve Closed Length)

GEAR

Timing Gear

Oil

Pump Gear

Width

GUIDE

BACKLASH

SEAT

Block

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

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

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

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

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

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

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

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

Free

Length (Approx.)

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

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

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

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

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

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

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

1.1890

1.1 920

0.0310

0.281

0

0.2805

0.7475

0.7500

0.0020

0.0010

0.0010 (0.025) 0.0080 (0.203)

(30.20) (30.28) (0.787)

(7.1 37) (7.1 25)

(1

8.99)

(1

9.05)

(0.051)

1

600

1.055

1.346 55

Ib

25

Ib

(0.025)

45º

1.1900

1.1930

0.0470

0.2820 5

0.281

0.7480

0.751

5

0.0040

(4.64

(26.80) (34.1

9)

(25

kg)

(11

kg)

0.0050 (0.1 27)

(30.23) (30.30)

(1.194)

(1 9.00) (1 9.09) (0.1 02)

3-2

P224

DESCRIPTION

CYLINDER BLOCK

Cylinder Bore Honed Diameter Maximum Allowable

Taper Out-of-Round

Main Bearing Inside Diameter (Without bearing) Main Bearing Inside Diameter (Installed) Camshaft Bearing Bore (Bearing Installed)

CRANKSHAFT

Main Bearing Journal Diameter Main Bearing Clearance Connecting Crankshaft End Play

CONNECTING ROD

Large Bore Diameter (Without bearing installed and rod bolts

properly torqued) Connecting Piston Pin Bushing Piston Pin Bushing Bearing to Crankshaft Clearance

CAMSHAFT

Bearing Journal Diameter Bearing Clearance End Play Lobe Height

Intake

Exhaust

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

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

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

Rod

Journal Diameter

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

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

Rod

Side Clearance

Bore

(Without bushing)

Bore

(Finished

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

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

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

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

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

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

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

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

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

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

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

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

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

bore)

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

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

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

MINIMUM

Inches

3.5625

2.1 870

2.001 5

1.3757

1.9992

0.0024

1.6252

0.0060

1.7505

0.0020

0.81 15

0.7504

0.0020

1.3740

0.001 5

0.01 10

(mm)

(90.49)

(55.55)

(50.84

(34.94)

(50.78) (0.061) (41.28) (0.1 52)

(44.46)

(0.051

)

(20.61) (1 9.06)

(0.051)

(34.90)

(0.038)

(0.279) 1

.

1670

1.1 570

Inches

3.5635

0.003

2.1 880

2.0040

1.3787

2.0000

0.0042

1.6260

0.01

20

1.751

0

0.01

60

0.81 25

0.7508

0.0033

1.3745

0.0030

0.0480

(29.64) (29.39)

(90.51)

(0.08)

(55.58)

(50.90)

(35.02)

(50.80)

(0.1 07) (41

.

30)

(0.305)

(44.48) (0.406) (20.64) (1 9.07)

(0.084)

(34.91) (0.076) (1

PISTON

Clearance in Cylinder

90°

to pin

Measure Piston Pin Ring Groove

Top

Middle Compression Ring Bottom Oil Control Ring

PISTON PIN

Clearance in Piston Clearance in Connecting

Diameter

PISTON RINGS

Clearance

Top

Ring End Gap in Cylinder

Bore

Width

Compression Ring

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

Groove

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

1.187

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

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

inch

below

top

of piston

.........

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

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

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

Rod

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

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

0.0070

0.7502

0.0800

0.1

880

0.00004

0.0002

0.7500

0.0020

0.01 00

(0.1 78) (1 9.06)

(2.032) (2.032) (4.775)

(0.001) (0.005)

(1 9.05)

(0.051) (0.254)

0.0090

0.7506

0.081

0

0.081

0

0.1 890

0.00064

0.0008

0.7502

0.0080

0.0200

(0.229) (1 9.07)

(2.057) (2.057) (4.801)

(0.01 6) (0.020) (1 9.06)

(0.203) (0.508)

DESCRIPTlON

INTAKE VALVE

Stem Diameter Clearance (Stem to Guide) Valve Face Angle

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

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

P224

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

0.3425 (8.700)

0.001

0

(0.025) 0.0025

44º

0.3430

(8.71 2)

(0.064)

INTAKE VALVE

Seat Cylinder Head Bore Diameter Seat Outside Diameter Valve

Seat

Valve

Seat

EXHAUST VALVE

Stem Diameter Clearance (Stem to Guide) Value Face Angle

EXHAUST VALVE

Seat Cylinder Head Bore Diameter

Seat Outside Diameter Valve Seat Width Valve

Seat

VALVE

Intake Inside Diameter

Exhaust

TAPPET

Body

Bore Clearance in

VALVE SPRINGS

Valve Spring Valve Spring Length

Spring Load (Valve Open Spring Load (Valve

GUDE

Inside

Diameter

.Valve Open

Valve Closed

SEAT

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

Width

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

Angle

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

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

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

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

SEAT

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

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

Angle

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

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

Diameter

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

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

Bore

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

INTAKE

Free

Length (Approx.)

AND

EXHAUST

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

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

Length)

Closed

Length)

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

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

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

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

1.5645 (39.74) 1

1.5690 (39.85) 1 .5700 (39.88)

0

0.031

0.341

0

0.0025

1.251

0

1.2550

0.031

0

0.3440

'0.7475

0.7500

0.0020

(0.787) 0.0470 (1.194)

(8.661) 0.3420 (8.687)

(0.064)

(31.78) (31.88) (0.787)

(8.738) (8.738)

(18.99) (1

9.05)

(0.051)

1.662 (42.21)

1.125

1.375

Ib

.

71 38

Ib

.

45º

44º

45º

.

.5655

0.0040

1.2520

1.2560

0.0470

0.3460

0.7480

0.751

5

0.0040

(28.58) (34.93) (32

kg)

(1 7

kg)

(39.76)

(0.1 02)

80)

(31. (31.90) (1.1

94)

(8.788) (8.788)

(19.00)

(1

9.09)

(0.102)

GEAR BACKLASH

Timing Gear Oil Pump Gear

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

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

3-4

0.001

0

(0.025) (0.025)

0.0050

0.0080

(0.1 27)

(0.203)

Assembly

The torque values given in Table 1 have been deter- Tighten all studs, nuts, and capscrews as required to

mined for specific applications. Standard torque values keep them from working loose. Refer to the must not be used where those listed in Table 1 apply. The engine assembly torques given here will assure proper tightness without danger of stripping threads.

threads must oil before torquing.

be

clean and lubricated with new engine

Torques

All

MANUAL

for

the

location

of

washers and capscrews.

PARTS

P216, P218, P220 TORQUE P216, P218, P220 TORQUE

DESCRIPTION SPECIFICATION DESCRIPTION SPECIFICATION

Gearcase Cover

Rear Bearing Plate Screws

Starter Mounting Connecting

Flywheel Capscrews

Base

Oil Oil Pump Valve Cover. Cylinder Head

Asbestos Gasket Graphoil Gasket

Gearcase Cover Rear Bearing Plate Screws Starter Mounting Connecting Flywheel Capscrews Oil Base Oil Pump Valve Cover.. Cylinder Head Nuts (Cold) Other

(w/Compression (w/o Compression

Rod

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

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

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

P224 TORQUE P224 TORQUE

DESCRIPTION SPECIFICATION DESCRIPTION SPECIFICATION

Rod

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

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

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

.....

Bolts

.........

Bolts.

.........

...........

Bolts

(Cold) Other

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

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

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

.....

Bolts

.........

Bolts..

........

...........

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

Washers)

....

.

Ft.-Lb. Nm

8-1

0

25-27 34-37

19-21 25-28 12-14 16-19 50-55 18-23 24-31

7-9 10-12 1-2 1-3

16-1 8 22-24 14-1 6 19-22

Ft.-Lb. Nm

8-10 11 -14 25-27 34-37 19-21 25-28 27-29 37-39 50-55 18-23 24-31

7-9 10-12 4-8 5-1 1

14 19

.

17

11-14

67-75

23

TABLE

1.

Intake Manifold

Mounting Screws..

Exhaust Manifold

Mounting Screws..

Other

1/4"

Stud and Nuts..

Other

5/16"

Stud and Nuts

3/8"

Stud and Nuts

Intake Manifold

Mounting Screws..

Exhaust Manifold

Mounting Screws..

Other

1

/4"

Stud and Nuts..

Other

5/16"

Stud and Nuts.

3/8”

Stud

and Nuts

Cylinder Block

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

Cylinder Block

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

Cylinder Block

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

Cylinder Block

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

Cylinder Block

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

Cylinder Block

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

..........

Ft.-Lb.

6-10 8-1 4 9-1 1 12-15

7-9 10-12

8-10 11-14

18-23 24-31

Ft.-Lb.

20-23 27-31

9-1 1 12-1

7-9 10-12

8-10 11-14

18-23 24-31

Nm

5

Special

The following special tools are available from Onan. For further information

900-0019.

Valve Seat Driver

Valve Guide Driver Oil Seal Guide and Driver Combination Bearing Remover (Main and Cam) Combination Bearing Driver (Main and Cam)

Flywheel Puller

Tools

see

TOOL CATALOG

Engine

Troubleshooting

ASOLINE ENGINE

FUEL

SYSTEM

INTERNAL ENGINE

LUBRICATION SYSTEM

THROTTLE AND GOVERNOR

M-1686

Oil

System

CRANKCASE

OIL

Refer to Periodic Maintenance Schedule (located in the

If

Operator's Manual) for oil change interval.

operating in extremely dusty, high ambient, or low ambient conditions, change oil more often.

Hot crankcase

His

spilled or splashed on skin. Keep

fingers and hands clear when removing

plug

and wear protective clothing.

Do

not overfill crankcase. Excess oil

oil

can cause burns

the

dl

if

drain

causes higher operating tempera-

tures and may cause foaming.

Run engine until thoroughly warm before draining oil.

Stop the engine, place a pan under the drain outlet and

is

remove the oil drain plug. After the oil

completely drained, clean and replace the drain plug. Fill crankcase with correct amount of oil. Refer to SPEClFlCATlONS for

Use

crankcase capacity.

SF,

fication

SF/CC, or SF/CD. Refer

oils meeting the

the proper viscosity grade of oil

to

use. Straight weight

API

classi-

chart to determine

oils are recommended for severe duty use and at temperatures above 32ºF (0ºC) for minimum oil consumption.

Crankcasepressure can blow oil and cause

check dl while

Oil level should be to the

the

engine

FULL

is

serious

burns.

Operating.

mark of the dipstick. Start

out

Do

hot

NOT

engine and run for a short time to check for oil leaks around the drain plug.

TORO

POWER

PLUS

Engine

FIGURE

FULL

ADD - REFER

1.

CRANKCASE

-

ALWAYS

LEAKAGE

TO

AMOUNT

OIL

FILL

REPLACE

OR

MAY

OCCUR

NOT

OVERFILL

ON

OIL

DIPSTICK

C-1000

I

COOLING

FIGURE

FINS

2.

OIL

FILTER

OIL FILTER CHANGE

Refer to the Operator’s Manual) for oil filter change interval. operating in extremely dusty, high ambient, ambient conditions, change oil filter more often.

Spin off oil filter element and discard clean filter mounting surfaceand make sure new gasket

is inserted in the element. Apply a thin film of clean oil to the gasket. Spin element down by hand until gasket just touches mounting pad and then turn down an additional

1

1/2-3/4

With oil in crankcase, start engine and check for leaks around filter element. Retighten only as much as necessary to eliminate leaks; do not overtighten.

Periodic Maintenenace Schedule

it.

turn. Do not overtighten.

(located in

or

low

Thoroughly

If

CRANKCASE BREATHER

The crankcase breather prevents pressure from building up in the crankcase. It also prevents oil contamination

or

by removing moisture harmful blow-by materials from the crankcase. These vapors are routed to the carburetor where they are mixed with incoming air and burned in the combustion chamber. A sticky breather valve can cause oil leaks, high oil consumption, rough idle, reduced engine power, and a rapid formation of sludge and varnish within the engine.

gasoline vapors and other

BREATHER

Crankcase

Breather

Service

If the crankcase becomes pressurized as evidenced by

or

oil leaks at the seals

excessive oil in the air cleaner

housing, use the following procedure to service.

Most parts cleaning solvents

are

flammable and could cause serious

personal injury

facturer’s recommendations

if

used

improperly. Follow the manu-

when

cleaning

parts.

P216, P218, P220

Remove the breather ure

3A).

Remove capscrew, flatwashers, valve cover,

pack, spring, washer,

tube

from the valve cover (Fig-

reed

valve, and breather baffle.

Discard gasket and clean all parts in part cleaning

solvent

Over tightening the valve cover can cause an air leak and allow dirt to

to

enter the engine. Be careful not

distort the valve

cover when tightening.

The reed valve must be flat with no sign of a crease. Assemble using a new gasket. Do not overtighten valve cover capscrew.

P224

Remove the breather hose from cap and valve assembly. Remove cap and valve assembly and wash in a suitable

if

solvent. Replace cap and valve freely. Puli pack out and wash in solvent.

of

operation shown in Figure

the valve, screens must be positioned as

38.

balls do not move

To

allow free

FIGURE

3A.

CRANKCASE

3B.

BREATHER

CRANKCASE

-

P216,

BREATHER

P218,

HOSE

CLAMP

-

P224

P220

CLAMP

PACK

6-2

PRESSURE

All

engines use an oil pump to provide a constant flow of oil to the engine parts. The oil supply collects in the oil base where it is picked up by the oil pump pick-up cup.

A

by-pass valve is used to control oil pressure. Drain oil before removing oil base and always use a new gasket when replacing the oil base.

Oil

Pump

The

oil

pump (Figure 4) is mounted behind the gear cover and is driven by the crankshaft gear. Inlet pipe and screen assembly are attached directly to the pump

A

body. a drilled passage in the crankcase. Parallel passages distribute oil to the front and rear main bearing and the oil bypass valve.

discharge passage in pump cover registers with

LUBRICATION

OIL PUMP PICK-UP CUP

Check oil pump thoroughly for worn prime it before reinstalling. Except for gaskets and pickup cup, component parts of the pump are not available individually. Install a new pump assembly are worn,.

Oil

By-Pass

The by-pass valve (located to the right and behind gear

cover) controls oil pressure by allowing excess oil to

the

flow directly back to

a

pressure to P216, P218, and P220, and about

the P224 at normal operating temperature. The valve is non-adjustable and normally does not need

maintenance. Determine if valve is operating correctly by inspecting plunger action as follows:

1.

Remove the cap screw located behind gear cover

and under governor arm.

2. Remove spring and plunger with a magnetic tool.

3.

Determine proper valve operation by checking the spring and plunger according to the following measurements:

maximum of about 20 psi (1

crankcase. The valve limits oil

Valve

30

parts.

Oil pump to

if

any parts,

38

kPa) on the

psi (207 kPa) on

OIL

PUMP ASSEMBLY

CRANKCASE TURNED

LEFT SIDE

ON

FIGURE

Circumferential grooves in the main bearings supply oil to connecting rod bearings through drilled passages from each main journal. front main bearing oil supply to the front camshaft bearing; rear cam bearing is splash lubricated.

Normal oil pressure should be

1500 rpm when the engine is at normal operating

temperature. value, inspect oil system for faulty components.

If

4.

OIL

PUMP

ASSEMBLY

A

drilled passage connects the

8

psi

(55

kPa) or higher at

pressure at 1500 rpm drops below this

Plunger Diameter

Spring

Free Length Load

4.

Check the valve seat and clean away any accumu-

lation, of metal particles which could cause erratic valve, action. Verify that the valve seat is not damaged.

Clean plunger and spring in parts cleaning solvent

5.

and install.

.....

when compressed to

..........

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

.;.

....

.2.6 ± 0.2 Ibs (11.6 ± 0.9

0.3105 to 0.3125 in. (7.89 to 7.94 mm)

1.00 inch

(25.4

mm)

N)

0.5

inch (12.7 mm)

Fuel

System

CARBURETOR

Note: See pages

All

carburetors have a fixed main jet An optional fixed

main jet is available for altitude compensation above

5,000

feet.

The carburetor idle mixture was set for maximum

efficiency at the factory and should normally not

disturbed. the ignition system is working properly and governor sensitivity is properly adjusted.

The carburetor has a limited adjustment range between stops of

within these limits; in to lean the mixture, out to richen.

seat.

If

replacing idle mixture screw, turn in until lightly

seated, then turn screw

P216, P218,

P224

the stop approximately centered.

If

adjustments seem necessary, first

±

1/8

Turn

in

only

and

carburetor. Replace limiter cap with the plastic

7-4-1,

74-2

for

Spec G

turn. The screw should only

forcing

tight

P220

the

mixture

will

damage

until

light

tension

back

carburetors, and

adjustment

out

1-1

be

screw

the needle

can

be

/4

turns

1

-1

Engines.

be

adjusted

felt

for the

/2

turns for

be

sure

and

Carburetor

1.

Start

(at least

Some equipment manufacturers may require higher

throttle stop

settings. Refer to equipment manufacturer's Operator's Manual for the correct rpm settings. When rpm settings are not specified by the equipment manu-factum, use the rpm settings listed and

2.

Move the engine

Bend the throttle stop screw on the carburetor controls engine speed. Adjust the throttle stop screw for

1000

3.

Adjust the governor low speed stop for

idle.

4.

Move the engine

Bend the high engine runs at

recommended

speed

the

engine and allow it to warm up thoroughly

10

Settings

minutes).

speed

and governor low

speed

in

3.

speed

control

or

turn the low

rpm idle (Figures 1 and

speed

to

the slow position.

stop on the governor

2).

1100

speed

control to the fast position.

stop on

the

equipment manufacturer's

the

governor

speed.

Steps

so

rpm

2

so

rpm

the

ADJUSTMENT

SCREW

I

LOW

SPEED

+

I

FIGURE

2.

CARBURETOR

ADJUSTMENTS

CARBURETOR OVERHAUL

Note: See pages

Carburetion

adjustments

passages

solution

In general, overhauling a carburetor consists of disassembly, a thorough cleaning, and replacement of won

parts.

General instructions for overhauling a carburetor are given below. Carefully note the position of all removing to assure correct placement when reassemb-

ling. Read through all the instructions before beginning for a better understanding of the procedures involved. Carburetor components are shown in Figure

explosion

igniter

problems that are not corrected by mixture

are

or

is a carburetor

Carburetor overhaul kits are available.

Do

near

the

7-4-1,

usually a result

worn

internal

overhaul.

Ignition

personal injury

not any flame,

fuel

system.

7-4-2

for

parts. The

of

fuel

Spec G Engines.

of

gummed-up

most effective

parts

3.

can cause

or

death

cigarette,

serious

by

tire

or

fuel

while

or

other

FIGURE

3.

Remove the four intake manifold cap screws and complete manifold assembly from engine.

4.

Remove carburetor from intake manifold.

3.

CARBURETOR

ASSEMBLY

Disassembly

1.

Remove main jet and idle adjustment needle.

lift

Removal

1.

Remove air cleaner assembly.

2.

Disconnect governor and throttle linkage, choke control, and

fuel

line from carburetor.

4.

7-2

2.

Remove attaching screws and separate upper and lower carburetor sections.

3.

Carefully note position of float assembly parts, then pull out retaining pin and float assembly.

Remove needle valve.

NEEDLE

\

BEND

TANG

TO

HERE

FUEL

BEND

HERE

FLOAT

TO

ARM

Cleaning and Repair

1.

Soak all metal components not replaced in car-

Do

buretor cleaner. other non-metal parts. Follow the cleaning manufacturer's recommendations.

2.

Clean all carbon from the carburetor bore, especially where the throttle and choke plates seat. not to plug the idle or main fuel ports.

3.

Dry out all passages with low pressure air Avoid using wire or other objectsfor cleaning which may increase the size of critical passages.

4.

Check the condition of the adjustment needle;

if

replace

damaged. Replace float

or damaged.

5.

Check the choke and throttle shafts for excessive play in their bore. This condition may necessitate replacement of the carburetor.

6.

Replace old components with new parts.

not soak non-metal floats or

Be

careful

(35

PSI).

if

loaded with fuel

Reassembly and Installation

1.

Install needle valve, main jet, and float assembly. Make sure float pivot pin is properly placed and float moves freely without binding.

2.

Turn carburetor on its side and measure float level (Figure Measure float drop (the distance from the top of carburetor body to top of float). Adjust only necessary.

3.

Position gasket on lower carburetor section and install upper carburetor section.

4.

Install idle adjustment screw, throttle stop screw, and fixed main jet plug.

5.

Mount carburetor on intake manifold and install assembly on engine.

6.

Connect governor and throttle linkage, choke control, and fuel line. Mount air cleaner assembly.

7.

Adjust carburetor and governor according to direc-

tions

4).

Adjust float level only

given

in

this section.

if

necessary.

if

PULSATING-DIAPHRAGM FUEL PUMP

Pulsating-diaphragm fuel pumps, on changes in crankcase vacuum to create a pulsating movement of the pump diaphragm. pistons move outward, a vacuum is created. This vacuum is transmitted to the pump diaphragm causing to pull back and suck fuel into the pump. pistons move inward, crankcase vacuum is reduced and the diaphragm return spring pushes the pump diaphragm forward, forcing fuel through the pump

outlet.

Fuel

Pump

Before testing make certain the fuel pump vacuum and

fuel

line connections are tight and

Test

Procedure

or

pulse pumps, rely

As

the engine's

As

the engine's

free

of

leaks.

it

Spilled fuel can serious

Thoroughly

7.

Remove fuel outlet line from fuel pump.

8.

Connect a pressure gauge to fuel pump outlet using

a piece of fuel hose with clamps.

9.

Start

seconds. While holding pressure gauge level with pump outlet record pressure gauge reading.

10.

Move throttle control engine to run for at least five seconds. While holding pressure gauge level with pump outlet record pressure gauge reading.

11.

Shut engine from fuel pump outlet Connect fuel outlet line

pump.

clean-up

engine and allow to idle for at least five

off

and remove pressure gauge hose

personal injury

any

spilled

to

high idle position and allow

ignite and

or

fuel.

cause

death.

to

fuel

Operate engine at an idle

1.

carburetor

that

Shut engine

2.

pump.

Connect a vacuum gauge to fuel pump inlet using a

3.

piece of fuel hose with clamps.

4.

Start

engine and allow to idle for

seconds. Record vacuum gauge reading.

Move throttle control to high idle position. Wait at

5.

least five seconds and record vacuum gauge reading.

Shut engine

6.

from fuel pump inlet. Connect fuel inlet line to fuel pump-

is

full

off

and remove fuel inlet line from fuel

off

and remove vacuum gauge hose

for

of fuel.

five minutes to ensure

at

least five

Replace the fuel pump

values

specified

in

TABLE

if

test readings are not within the

1.

TABLE

1

PULSE PUMP TEST SPECIFICATIONS

ENGINE

SPEED VACUUM

Low Idle

High Idle

--

PUMP

INLET

(Minimum)

2.6

inches

of mercury

2.6

inches

of mercury

PUMPOUTLET

PRESSURE

(Minimum)

1.7

--A

psi psi

7-4

Supplement to

492-4006,

492-4007

Date: 1-95

P216/P218/P220/P224/P220V

Service Manual

PURPOSE

This supplement transmits the revisions to the Service Manual necessary for covering the

Spec G engines listed above. Note that the nameplate on a Spec G engine will

have the statement: “This engine meets ULGE engines.”

To

satisfy California emissions regulations, Spec G engines have internal engine

modifications and precision-manufactured carburetors with tamper-resistant fuel mixture

jets. It should therefore be noted that, other than installing the optional high-altitude jet

(Figure 4a), fuel mixture adjustments should not be attempted. Nor should. the carburetor be overhauled. Instead, a malfunctioning carburetor (see

Troubleshooting)

should be replaced.

1995-1

998

California emissions regulations for

Engine

California users should note that unauthorized modifications or replacement of fuel, exhaust, air intake, or speed control system components that affect engine emissions are prohibited by California regulations and that the optional high-

is

altitude main jet replacement of the generator set label

not intended for use

in

California. Modification, removal or

is

also prohibited.

7-4-1

CARBURETOR (BEGINNING

SPEC

G)

Carburetor

Other than replacing the carburetor main fuel jet (fixed-type) with the optional high-altitude jet (Fig-

ure

&),

tempted. Instead, a malfunctioning carburetor should placed. Before replacing a carburetor, however,

make certain generator adjustments and repairs have been formed and functioning (see

To

remove the carburetor, remove the disconnect the fuel line and choke and throttle linkages and unbolt the carburetor from the intake manifold. When mounting the carburetor always use a new gasket. Readjust the choke and throttle cables and engine speed as instructed in the engine equipment Operator's Manual.

Carburetor

If

the engine

feet

(1,524

buretor main fuel jet high-altitude jet (which has a slightly smaller fice).

Replacement

fuel mixture adjustments should not

Nor

should

1)

2)

High-Altitude

is

metres),

the

carburetor

that all other necessary engine and

that the carburetor is actually

Engine

operated at an altitude above

Troubleshooting).

it

is

recommended that the car-

be

replaced with the optional

be

Jet

(Optional)

overhauled.

air

cleaner,

be

at-

be

re-

per-

mal-

or

5,000

ori-

LEVER

PUMP

STOP

SCREW

PLUG

OVER IDLE

MIXTURE

NEEDLE

main

(8

mm)

To

fuel

jet,

use

wide blade.

avoid slipping and gouging the

a screwdrlver with a

5/16

inch

REMOVE

ACCESS

CAP

TO MAIN

FIGURE

FOR

JET

4a.

CARBURETOR

MAIN

(shown

CHOKE

FUEL

JET

enlarged)

AIR

PLATE

AIR

CLEANER

ELEMENT

.

AIR

CLEANER

If air cleaner becomes

FIGURE

too

5.

dirty,

engine will not receive sufficient

to

run properly. Symptoms:

Loss

of power, flooding,

hard starting and overheating.

Engine is equipped with a paper element. equipped with an element wrapper,

25

cleaned, and oiled every

hours of operation; more

If

the engine is

it

must be removed,

often under extremely dusty conditions.

1.

To

clean element wrapper, wash in water and detergent (Figure squeezing like

Distribute one tablespoon of SAE

5).

Remove excess water by

a

sponge, and allow to dry thoroughly.

30

engine oil evenly around the precleaner. Knead into precleaner and wring out excess oil.

2.

Depending on conditions in which the engine is

operating, the inner paper element should be

replaced whenever it becomes excessively dirty or

oily.

AIR

air

CLEANER

ASSEMBLY

GOVERNOR SENSITIVITY

These engines are adapted for use where a wide range of speed settings is desired. Engine speed is controlled at any given point between minimum and maximum by simply shifting the throttle lever on the control panel until the desired speed is reached.

A

reliable instrument for checking engine speed is required for accurate governor adjustment. Engine speed can be checked with a tachometer.

Check the governor arm, linkage, throttle shaft, and lever for binding condition or excessive slack and wear

A

at connecting points. will cause the governor to act slowly and regulation be poor. Excessive looseness may cause a hunting condition and regulation could be erratic. Work the arm back and forth several times by hand while the engine is idling to check for above conditions.

binding condition at any point

will

and wear

Never run engine

out

removed.

rings causing excessive blow-by.

Dirt

will enter engine

with

air cleaner

THROTTLE

SCREW

STOP

GOVERNOR

SIDE

PULL

CONTROL

LINKAGE

GOVERNOR

FIGURE

6.

VARIABLE

SPEED

GOVERNOR

FRONT

ADJUSTMENTS

PULL

SPRING

GOVERNOR

If

the governor is hunting

adjust as follows (Figure

1.

Disconnect linkage

2.

Push linkage

(A)

or

not operating properly,

6):

(A)

from one of holes

and governor arm

(C).

(B)

as far back

toward carburetor as they will go.

3.

Holding linkage and governor arm toward direction

of carburetor, insert end of linkage into whichever

(C)

hole

between two holes, insert in next hole

in governor arm lines up the closest.

out.

If

On side

factory in

from

pull

governors the governor spring

the

third

hole of the governor arm (third hole

is

set by the

pivot). On front pull governors the governor spring is set by the factory in the second hole of the governor arm adapter (second hole from pivot).

loop

sensitivity, move spring pivot.

To

decrease sensitivity, move spring loop into a

into a hole closer to the

To

increase

hole farther away from the pivot. After sensitivity has been set, recheck the low speed rpm setting. Adjust

if

necessary.

Ignition and Battery Charging

IGNITION SYSTEM DESCRIPTION

This engine is equipped with an electronic battery

ignition system. Both spark plugs fire simultaneously, thus the need for a distributor is eliminated. The electronic ignition module is located on the enginegear

cover behind the flywheel. The module receives a timing

signal from magnets within the trigger ring which rotates

with the engine crankshaft (Figure

is

ignition

suspected of malfunctioning, proceed as

follows:

1).

If

the electronic

Failure to ground spark tester

result in ignition

of

away from

cyiinder gases and may cause

spark

plug hole may

severe personal injury.

2.

Pull spark plug wires

off

spark plugs and remove spark plugs. Connect an approved spark tester to each of the spark plug wires and ground them away from spark plug hole. Turn key on and crank engine over for

seconds while watching for spark.

If

5

spark occurs regularly, the problem is not in the

ignition system. If no spark occurs, go to step

3.

Never put jumper lead to the coil negative terminal. This will cause

failure of

3.

Connect a jumper lead directly from the positive battery terminal to the positive

the

electronic ignition module.

(+)

coil terminal

(smaller diameter of the two threaded posts). Crank

If

engine over while watching for spark.

spark occurs, the problem is in the low oil pressure cut out switch (if equipped) or related wiring, the lubricating system (low oil pressure), or in the other circuitry bringing voltage to the coil.

4.

step

If

no spark occurs, go to

a

IGNITION MODULE

FIGURE

1.

Check all electrical connections to be sure they are clean and tight. wiring is intact, go to step

1.

IGNITION

MODULE

If

all connections are good and

AND

2.

TRIGGER RING

ES-1670

The electronic ignition will

deliver full voltage to the spark

plugs even when rotated by hand.

Care

should

taken to avoid an electrical shock.

Failure to remove spark plugs before turning engine over may

result in engine starting, which may cause severe

personal injury.

be

4.

Refer to proper resistance. step

5.

Connect positive side of voltmeter to negative

5.

IGNITION

COIL

section to test coil for

If

coil checks out good, go to

coil terminal (larger diameter of the two threaded

of

posts) and negative side

voltmeter to engine ground. Turn key on and rotate flywheel slowly by hand while observing voltmeter. Voltage should

1-1.5

switch between battery voltage and,

for each revolution. If voltage does not switch properly, replace ignition module.

Never put

negative terminal.

B+

lead to the coil

This

will cause

failure of the electronic ignition module.

6.

Install spark plugs and wires. being replaced, be sure to connect new ignition module to positive black lead from module to negative

If

ignition module is

red

lead from

(+)

terminal of coil,

(-)

terminal of

coil.

(-)

8-

1

IGNITION TIMING

The ignition timing is preset at the factory and is not adjustable.

to

make an approximate check of the ignition timing

using reference marks on the blower housing and flywheel (Figure 2). This check can be performed by a continuity test.

For

troubleshooting purposes, it is possible

4.

Rotate the flywheel slowly by hand in the clockwise direction until the voltmeter reading switches from approximately 1 volt to battery voltage. At this point, one of the chaff screen screws should lie between the two reference marks on the blower housing. To

be

recheck timing, the flywheel must

rotated another complete revolution in the clockwise direction. Moving the flywheel back and forth across the reference timing mark will not activate the electronic ignition control.

5.

Install spark plugs and wires.

,

IGNITION

To

test primary and secondary windings within the

COIL

ignition coil first make sure the ignition power is off and coil is at room temperature of 70°F (21 "C).

BLOWER

TIMING

M-1675

FIGURE

2.

IGNITION TIMING

MARKS

Continuity Test

1.

Pull spark plug wires

off

spark plugs and remove

spark plugs.

Failure

to

remove spark plugs

before turning engine over may result in engine starting, which may cause severe personal injury.

1. Use a Simpson 260

2. Place

a

black lead on negative

red lead to positive

VOM

or equivalent.

(+)

(-)

coil terminal and

coil terminal. Primary

resistance should read between 2.90-3.60 ohms.

3.

Change resistance setting on ohmmeter. Place ohmmeter leads inside of spark plug cable holes (Figure between

4.

If

3).

Secondary resistance should read

14,500-1

9,800

ohms.

either of the above resistances are not within

specification, replace coil.

2.

Turn ignition on.

3. Connect a voltmeter between the negative

(-)

coil terminal (larger diameter of the two threaded posts) and a good engine ground.

The electronic ignition will

d

deliver full voltage

plugs even when rotated

by

hand. Care should

to

the spark

be

taken to avoid an electrical shock.

FIGURE

3.

COIL TEST

SPARK PLUGS

Keep the battery terminals clean and tight. Push the cable terminal down flush with or slightly below the top

Check or replace spark plugs as recommended in the

Periodic Maintenance Schedule

(located in Operator's

Manual). Replace spark plugs that show signs of fouling

or

electrode erosion.

of the battery post (Figure coat the terminals with a light application of petroleum jelly or grease to retard corrosion.

Poor contact at the battery cable connections 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. recommended battery tools when disconnecting leads to avoid mechanical battery damage.

6).

After making connections,

is

often a

Use

FIGURE

4.

SPARK PLUG GAP

BATTERY INSPECTION

Ignition can cause severe personal injury.

not smoke while servicing batteries.

Check battery cells with a hydrometer (Figure

Specific gravity reading should be between 1.260 and

1.290 at 77°F (25°C).

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 or dirt will accelerate discharge and battery failure.

of

explosive battery gases

SPECIFIC

GRAVITY READING

SHOULD BE

1.260

at

(25°C)

5).

FIGURE

BATTERY

6.

BATTERY CABLE CONNECTION

POST

BATTERY JUMP STARTING

Occasionally, a weak battery using a charged booster battery. If jump starting is necessary, the following procedure is recommended to prevent starter damage, battery damage, and personal injuries.

1. Disconnect engine load.

it

may be necessary to jump start (charge)

FIGURE

5.

SPECIFIC GRAVITY TEST

2.

Use a battery of the same voltage (1 2V) as is used with your engine.

3.

Attach one end of the positive booster cable (red) to

(+)

the positive

terminal of the booster battery.

Attach the other end of the positive cable to the

(+)

positive

terminal of your engine battery.

Do

each

other

negative cable

because

not allow

it

will short

the

posltive

ends

to

the

battery causing battery hazardous arcing, which can cause severe sonal injury.

4.

Attach one end of the negative booster cable (black)

(-)

to negative

terminal of booster battery. Attach other end of negative cable to a solid chassis ground on your engine.

5.

and

touch

per-

Never

tery.

to

open

explode.

flame

or

Never

an electrlcal spark because a battery

creates highly explosive hydrogen

6.

Turn ignition switch to

FLYWHEEL ALTERNATOR

jump

start a frozen

To

do

so

expose

ON

to start engine.

can cause

the

battery to an

gas.

bat-

the

STATOR

Weak ignition trouble in

spark

or

a discharged battery indicates

the

charging system. Before testing the engine's charging system, always check the battery for serviceability.

MOUNTED BEHIND

BLOWER WHEEL

TOSTARTERORBATTERY

REGULATOR MUST BE GROUNDED

THROUGH MOUNTING BOLTS

VOLTAGE REGULATOR CONNECTIONS

ES-1333-1

FIGURE

7.

FLYWHEEL ALTERNATOR

SYSTEM

CAUTION:

EO-1532

Keep these points in mind when testing or servicing the flywheel alternator:

1.

Be

sure engine is being run long enough and fast enough to recharge battery after each start. Charging system tests require a full charged battery. Alternator output is reduced in direct proportion to engine rpm.

Also,

power required for accessories reduces power

available to recharge battery.

2.

The regulator-rectifier has built in protection against open circuits or short circuits on the alternator

(B+)

output regulator-rectifier to shut off and appear as

terminal. Either condition will cause the

if

it is not functioning. Priortochecking the regulator-rectifier, check all wiring between the regulator-rectifier terminal and the battery positive

(+)

terminal to

B+

assure it is free of open circuits, resistances or short

if

circuits. Also,

the battery is extremely discharged it may have insufficient power to “turn on” the regulator-rectifier.

3.

Be sure regulator-rectifier plug (connector) is inserted properly. Plug must bottom in receptacle; this eliminates any resistance due to a poor connection. Keep clean and tight.

4.

Make sure alternator stator leads are not shorted

together.

ALTERNATOR

Use a volt-ohmmeter, such as the Simpson

OUTPUT

TEST

270,

when

testing the charging system.

1.

Check battery voltage with unit not running. If not

1)

within specifications (Table

to

step

proceeding

2.

With the engine running, check the battery terminal

2.

charge battery before

voltage (regulator output) using a DC voltmeter. Voltage output should be within the values specified

in Table 1. If voltage is greater than specified,

If

replace regulator-rectifier assembly. less than specified, proceed to step

3.

Examine all wires for loose, corroded, broken con-

voltage is

3.

nections, short circuits, etc. Check fuses. Repair as needed to assure complete circuits from regulator-

B+

rectifier and from battery negative rectifier case.

terminal to battery positive

(-)

terminal to regulator-

If

battery voltage remains low with

engine running, proceed to step

4.

Disconnect plug from regulator-rectifier and test

the AC voltage at the plug with engine running.

4.

(+)

terminal

If

AC

voltage reads more or less than specified in Table 1,

proceed to step

5.

If

AC voltage is as specified but

DC voltage is low, replace regulator-rectifier.

5.

Be sure regulator-rectifier has a good ground connection. Mating surface for mounting must be clean and fasteners tightened properly.

6.

Never reverse the battery leads.

1800

to

When the engine is running between

2600

observe the panel ammeter (if not already equipped,

If

connect a test ammeter). proceed with the

Alternator Output Test.

no charging is evident,

rpm,

5.

Use the

Rx1

scale on the ohmmeter for detecting an

open or ground in the stator (unit not running).

Disconnect plug from the regulator-rectifier. Connect one ohmmeter test lead to a stator wire,

connect the other test lead to ground. Reading

should show an open (no continuity).

doesn’

t,

If

it

stator must be replaced. If reading shows no continuity connect one ohmmeter lead to each wire

1

coming from the stator. Refer to Table

ance specifications.

replace stator.

If

resistance is not as specified,

If

stator resistance readings are as

for resist-

specified and windings are not shorted or open, low

AC voltage may

blower wheel assembly must

be

due to

loss

of magnetism.

be

replaced.

If

so,

TABLE

1.

TESTING

20

AND

35

AMPERE

SYSTEMS

STATOR

RESISTANCE

PROCEDURE

13.6

to

14.7 VDC Approximately 24 VAC

Refer

Output

0.06

0.10

0.06

to

Alternator

to

0.10

to

0.19

to

0.1

0

Test

Ohms

TYPICAL

WIRING

DIAGRAM

*AMMETER

(OPTIONAL)

WITH

OIL

PRESSURE

ACCESSORIES

START

LOW

PRESSURE WARNING

LIGHT

OR

HORN

SWITCH

FOR

LIGHT

&ye-

STARTER

OIL

SWITCH N C

PRESSURE

*FUSE

*AMMETER

These typical wiring diagrams show the basic wiring necessary

for

operation of the engine. Your engine may

STARTER

differ in circuitry and features depending on how the equipment manufacturer chose to configure the final product.

Starting

System

ELECTRIC STARTER 1.

Normally the starter will require little or no service other

if

than possible brush replacement However, accident or misuse, the starter requires service or from starter.

will

overhaul, the following necessary to perform this service.

Service

When starting engine, note starter motor action. The pinion gear should mesh quickly with flywheel ring gear solenoid (Figure and spin engine. Once engine starts and solenoid opens, the starter should disengage and stop. cranks engine slow, or not at all, check start circuit remove solenoid. components. Failure to crank is normally caused battery charge, defective battery cables, corroded or poor connections, or low temperatures. these variables, starter continues to crank slowly, starter must be removed and repaired.

Starter Removal

Accidental starting

cause severe personal injury death. Disconnect made

to

the engine, controls,

the

battery

provide the information

If

of

the

cables when repairs are

or

housings.

through

If

starter

by

low

after checking in assembly. Remove the

engine can

or

Remove both battery cables from battery. Disconnect ground cable first.

2.

Disconnect battery cable and electrical lead wires

3.

Remove starter motor.

Starter Disassembly

1.

Remove

2.

Remove the

3.

Scribe a mark across frame and rear bracket to aid

4.

Remove rear bracket and frame assembly.

5.

Carefully remove armature and lever from front bracket. Note direction of lever and retainer.

6.

Remove the move the rear bracket

7.

Remove brush holder assembly from the frame by

pulling the brushes out

“M”

terminal nut and wire lead from

1).

two

solenoid mounting screws and

two

through bolts.

two

brush mounting screws, and re-

FRONT

BRACKET

RETAINER

FIGURE

SOLENOID

1.

ARMATURE

STARTER

MOTOR

THROUGH

SCREW

Push stopper toward pinion and remove snap ring

8.

(Figure

Remove stopper and overrunning clutch from

9.

armature shaft.

ST

2).

CLUTCH

\

STOPPER

a=-

FIGURE

10

Inspect starter for damaged

11.

Repair

needed.

Starter

1.

2.

Assembly

Install seal in nose housing. Install overrunning clutch on the armature shaft.

Slide stopper on the armature shaft. Position snap ring in groove in armature shaft.

2.

REMOVING OVERRUNlNG

or

replace all damaged or worn parts as

worn

CLUTCH

parts.

SNAP

RING

4.

Lubrication: When grease to each of the following points (Recommended grade: Multitemp PS

Armature shaft spline Both bushings (Both ends of armature) Stopper on armature shaft Pinion

Sliding portion of lever

5.

Fit overrunning clutch into lever, and install with

armature in the front bracket

6.

Install lever retainer and spacer. Position frame

assembly over armature on the front bracket.

7.

Install brush holder assembly. Position brushes in brush holder. Make certain positive lead wires are not grounded.

gear

starter

motor is assembled apply

No.

2):

I

3.

Pull stopper all the way over snap ring (Figure may be necessary to tap snap ring into groove with a punch while maintaining tension on stopper.

3).

It

8.

Install washers, as required, on the rear end of armature shaft to obtain an armature shaft thrust gap of

washers are required

9.

Install rear bracket. Secure brush holder to rear

bracket with

0.002

to

0.02

Table

1.

Starter

Brush Retaining Screws Through

Bolts

two

machine screws.

inch

(0.05

to

0.5

if

rear bracket is replaced.

Assembly

Torques

mm). New

10.

Install and tighten the two through capscrews.

11.

Install solenoid plunger in lever. Secure solenoid to front bracket with two machine screws.

12.

Install wire lead to the terminal

13.

After assembly, adjust pinion clearance. Pinion clearance should

if

not, check as follows (Figure

A.

Connect starter to a battery. Close switch. This

be 0.02

to

0.08

“M”

on solenoid.

inch

(0.5

4):

to

2.0

will shift pinion into cranking position.

B.

Push pinion back by hand and measure pinion clearance. If clearance does not fall within the specified limits, adjust by adding or removing

shims located between solenoid and front

bracket Adding shims decreases clearance; removing shims increases clearance. Shims are included with replacement solenoid.

mm);

COMMUTATOR

FIGURE

BARS

5.

TESTING ARMATURE FOR GROUNDS

ES-1001

FIGURE

PINION

BATTERY

4.

PINION CLEARANCE ADJUSTMENT

Testing Armature

for

an Open Circuit:

Using an

ohmmeter, check for continuity between the commutator

If

there

is

segments. segments are open and armature must

Testing Armature

locating shorts in the armature (Figure

no continuity (high resistance), the

be

replaced.

tor

a

Short

Circuit:

Use a growler for

6).

Place armature in growler and hold a thin steel blade (e.g. hacksaw blade) parallel to the core and just above rotating armature in growler.

A

shorted armature will

cause the blade to vibrate and be attracted to the core.

it

while slowly

If

armature is shorted, replace with a new one.

Inspection and Testing

Inspect the starter components for mechanical defects before testing for grounds or shorts.

Testing Amature

tor

Grounds: Touch armature shaft

or

core and the end of each commutator bar with a pair of

ohmmeter leads (Figure

5).

A

low ohmmeter reading indicates a grounded armature. Replace grounded armature.

FIGURE

6.

TESTING ARMATURE

FOR

SHORT

ES-1002

CIRCUITS

Commutator Inspection:

colored, clean with number

If

commutator is dirty or dis-

00

to

000

commutator

paper. Blow grit out of armature after cleaning.

If

commutator is scored, rough, or worn, turn it down in a

lathe.

Overrunning Clutch:

Inspect pinion and spline teeth for

wear or damage.

If

pinion gear is worn or damaged, inspect flywheel ring

It

gear also. Rotate pinion.

should turn free when turned in one direction, and lock when turned in the opposite direction.

Field Coil:

between brushes.

Use an ohmmeter to check for continuity

If

there is no continuity, the field coil is open and must be replaced. With field coil mounted in the frame, check for continuity between the field coil and

if

frame. Replace frame assembly

Brushes: Clean around brushes and holders, wiping

all brush dust and dirt.

.4528

inch

(1

1.5

If

brushes are worn shorter than

mm) replace them (Figure

WEAR

LIMIT

there is continuity.

off

7).

Do

not clean overrunning clutch in

or

solvent

Washing the clutch will cause

Solenoid:

Push solenoid plunger in and release

liquid cleaning solution.

the

grease

to

leak out.

it.

The plunger should return to its original position. While holding plunger all the way in, check for continuity

“M”

and

“B’.

If

between terminals replace the solenoid (Figure

there is no continuity,

8).

After replacing solenoid

check pinion clearance.

ES-1345

FIGURE

7.

BRUSH

WEAR

LIMIT FIGURE

Check for shorts between positive side of brush holder

If

and brush holder base.

there is continuity, replace

holder assembly. Check for free movement of brushes.

All

brushes should move freely in the brush holders.

8.

SOLENOID TERMINALS

Bushings:

of wear

If

either the front or rear bushing show signs

or

damage, replace them. Bushing and rear

bracket are replaced as an assembly. Check armature

if

shaft thrust gap

rear bracket is replaced.

Remove front bushing by tapping bushing from inside

with a

inch tap.

Do

not remove cap from front

7/16

bracket. Thread capscrew, same size as tap, into

bushing. Using a slide hammer remove bushing from front bracket. Press new bushing into front bracket. Use care not to distort inside diameter of bushing.

Brush Replacement

at the brush.

Be

1/4 to 3/8 inch

Cut old positive brush from pigtail

careful not to damage field coil. Clean

(6.5

to

9.5

mm) of brush end of pigtail

with sandpaper or emery cloth. (Figure

PIGTAIL

STILL

TO

ATTACHED

FIELD

COIL

I

9).

inch)

Starter

Mounting

Before installing starter motor. make sure the starter mounting Surface on the engine base is clean and free of oil.

To install starter use the following procedure. The starter pinion gear lash does not require adjustment

1.

Install starter motor and torque mounting capscrews

to that specified in

2.

Connect battery cable and wires to starter. Connect

ASSEMBLY

TORQUES.

battery) cables to battery. Connect ground cable last

SMALL

-SOLDER

CHAMFER

REPLACEMENT

MUST

EXTEND

BRUSHSURFACE

BRUSH

NOT

BEYOND

Push prepared end of pigtail lead into hole in replacement brush from the small chamfered side. Solder pigtail lead to replacement brush on the large chamfered side,

50/50

using 240/325 Watt soldering iron.

tin/lead, rosin core solder and a standard

Use

a file to remove any

excess solder that may extend beyond brush surface.

To prevent

stiffening of pigtail lead do not use excessive

amount of solder

Pigtail surface

and

lead must not protrude from

on

the

soldered side

of brush.

heat.

Engine

Disassembly

DISASSEMBLY/ASSEMBLY

When complete engine disassembly is necessary, first

remove all complete assemblies. Individual assemblies such as fuel pump and carburetor can be disassembled gear. and repaired at another time.

Suggested Disassembly Order

1.

Drain crankcase. Disconnect all exhaust and electrical lines.

2.

Remove engine from its mountings and place on a

3.

suitable bench or work stand.

4.

Remove all housings, shrouds, blower housings,

etc.

Remove flywheel, using a puller.

5.

Remove ignition trigger and gear cover, being

6.

careful to protect oil seal from keyway damage.

7.

Remove crank gear, using a gear puller and ring. Remove all accessories such as oil filter, starter,

8.

intake manifold, fuel lines, spark plugs, etc. Remove oil base, oil pump and cylinder heads.

9.

Remove valves, springs, lifters, etc.

10.

11.

Remove camshaft and gear assembly. Remove connecting rods and pistons.

12.

Remove rear bearing plate, crankshaft, and front

13.

bearing.

Keep all parts in their respective orders. Keep valve

to

assemblies together. Return rod caps

pistons. Analyze the reasons for parts failure.

Suggested Assembly Procedure

Engine assembly is normally the reverse of the disassembly procedure, observing proper clearances and torques. Use a torque wrench to assure proper tightness. Coat the internal engine parts with assembled. After the internal engine parts are assembled, the engine should turn over by hand freely. Use only genuine Onan parts and special reassembling your engine.

their respective

oil

as

they are

tools

when

1.

Use proper bearing driver to install front main bearing after coating

2.

Insert rear main bearing in rear bearing plate.

3.

Insert crankshaft, rear bearing plate, and crankshaft

4.

Install pistons and connecting rods.

5.

Install camshaft and gear assembly; align crank

gear mark with cam gear mark.

6.

Install valve assemblies, oil pump, oil base, and cylinder heads.

7.

Install all accessories such as oil filter, starter, fuel lines and spark plugs.

8.

Install gear cover with oil seal, trigger ring, and

flywheel.

9.

Check valve clearance.

10.

Install all housings and air cleaner.

11.

Fill

crankcase with oil.

Operation

Start engine and check oil pressure. Run for approx-

15

imately temperatures. Check for oil leaks, fuel leaks, and exhaust leaks. Adjust carburetor and sensitivity.

Testing Compression

The compression tester is used to determine the

condition of valves, pistons, piston rings and cylinders.

To

check compression:

1.

Run the engine until thoroughly warm.

2.

Stop engine and remove spark plugs.

3.

Remove air cleaner and place throttle and choke in

the wide open position.

4.

Insert the compression gauge in one spark plug hole.

5.

Crank the engine and note the reading.

Refer to There may be variations due to equipment, temperature, atmospheric conditions and altitude. These pressures are for a warm engine at cranking speed (about

rpm).

minutes to bring engine to operating

SPEClFlCATlONS

it

with a light film of oil.

governor

for compression pressures.

for speed and

300

10-1

Tappet Adjustment

The engine is equipped with adjustable valve tappets. The valve tappet clearance should be checked and

adjusted as specified in the

Schedule

(located in the Operator’s Manual). Adjust the

Periodic Maintenance

valve clearance only when engine is at ambient temperature. Proceed as follows:

1.

Remove ignition key to prevent accidental starting.

2. Remove all parts necessary to gain access to valve tappets.

3.

Remove spark plugs to ease the task of turning the

engine over by hand.

4.

Place a socket wrench on the flywheel capscrew

and rotate the crankshaft in a clockwise direction

until the left intake valve (viewed from flywheel end) opens and closes. Continue turning the crankshaft until the TC mark on the flywheel is lined up with the TC mark on the gear cover. This should place the left piston (#1) at the top of its compression stroke. Verify that the left intake and exhaust valves are closed and there is no pressure on the valve lifters.

5.

The correct feeler gauge for the valve adjustment

Sf

(see

EClFCATlONS)

valve cap (P216, P218, P220) and tappet; a 0.002 inch

should pass freely between

or

valve stem (P224)

(0.05

mm) thicker gauge

should not (Figure 1).

To

correct valve clearance, use a 7/16 inch open

6. end wrench to turn the adjusting screw to obtain the correct clearance. The screw is self-locking and

A

will stay where it is set.

9/16 inch (14 mm) open end wrench is required to hold the tappet while turning the adjusting screw.

7.

To

adjust valves on the right hand cylinder, turn

engine one complete revolution and again line up

mark on the flywheel and the TC mark on the gear

cover. Then follow adjustment procedure given for

left hand cylinder.

8. Replace all parts removed in Step 2. Tighten all screws securely. Torque manifold bolts to specified torque.

VALVE

A

properly functioning valve system is essential for good

SYSTEM

engine performance. All engines utilize an L-head type valve design as shown in Figure

1.

Access to the valve system can be obtained by removing the cylinder heads and the valve covers on top of the engine.

A

valve spring compressor must be used to remove valves from the cylinder block.

A

valve stem seal is used on the intake valve guides. This seal must be replaced each time the valve is removed.

Place valves, springs, retainers, and tappets in a rack as they are removed from cylinder block

so

they can be identified and reinstalled in their original locations. Discard old valve stem seals and replace with new ones during assembly.

Use the following procedures to inspect and service the valve system.

Inspection

Clean carbon from the valves, valve seats, valve guides, and cylinder block.

Valves:

Check the valve face for evidence of burning,

warpage, out-of-round, and carbon deposits. Burning and pitting are caused by the valve failing to

seat tightly. This condition is often caused by hard carbon particles on the seat. It may also be due to weak valve springs, insufficent tappet clearance, warpage, and misalignment.

CLEARANCE

VALVE

VALVESEAT

INSERT

FIGURE 1A. INTAKE VALVE ASSEMBLY

VALVE VALVE VALVE

GUIDE

STEM

KEEPERS

VALVE

CLEARANCE

VALVE

RETAINER

-

ADJUSTING

VALVE

INSERT GUIDE

P216, P218, P220 FIGURE 1B. INTAKE VALVE ASSEMBLY

10-2

SEAT

VALVE

STEM

VALVE

CLEARANCE

VALVE

KEEPERS

VALVE

RETAINER

-

P224

VT-1035

Warpage occurs chiefly in the upper stem due to

its

exposure to intense heat. Out-of-round wear follows when the seat is pounded by a valve whose head is not

If

in line with the stem and guide.

or warped, or

if

the stem is worn, install a new valve.

a valve face is burned

Too much clearance in the intake guide admits air and oil into the combustion chamber, upsetting carburetion, increasing oil consumption, and making heavy carbon deposits. Carbon reduces heat dissipation. Clean metal is a good heat conductor but carbon insulates and

retains heat This increases combustion chamber temper-

atures which causes warping and burning.

Unburned carbon residue gums valve stems and causes them to stick in the guide. Deposits of hard carbon with sharp points projecting become white hot and cause pre-ignition and pinging.

or

Refinish valves that are slightly pitted

If

accurate valve grinder.

valves are badly pitted or have

burned on an

a thin margin when refacing, replace them.

Drivlng

the

not to strike guide strike

tappet

bores

Valve Guide Installation

covered with crocus cloth through valve guide

out

old

guides can damage

e

guide

or

tappet

bores

with driver

during removal.

Run a small polishing rod

bores.

or

Be

allow

careful

guide

holes

to

clean ,out carbon and other foreign materials. Place a

new gasket on the intake valve guide, and coat the outer

edge

of each new guide with oil. Place guide in cylinder

11

/32

block and press in until guide protrudes

(8.7

mm) from valve

box

side of block. A suggested

method of installation is shown in Figure

ROD

3.

inch

FIGURE

Stems and Guides:

guidesfor wear (Figure

2.

VALVE

STEM

AND

VALVE

GUIDE

INSPECTiON

Always check valve stems and

2).

Use a hole gauge to measure the valve guide. When clearance with stem exceeds that specified in either valve or guide or both, as may

DIMENSIONS AND CLEARANCES

be

necessary.

replace

Always regrind seat to make concentric with the newly installed guide.

Worn valve stem guides can be replaced from inside the valve chamber (a seal is provided behind the intake valve guides only). The smaller diameter of the tapered valve guides must face toward the valve head. Tappets are also replaceable from the valve chamber after first removing the valve assemblies.

seals. Each time the valves are removed from cylinder block, a new

Valve Guide Removal:

Before removing valve guides, use an electric drill with a wire brush to remove carbon and other foreign material from top surface of guides. Failure to perform this operation may result in damage

the

guide bores. Drive the guides out with a hammer

to and valve guide drive.

only as valve stem damage will

VALVE

5/16-18

HEX,

(2

REQUIRED)

THREADED ROD

FIGURE

Valve Stem Seals (intake only):

3.

VALVE

GUIDE

Do

seal

must be used when valve is reinstalled.

not

remove valve after seal

installed. valve can

far

as the groove in valve

seal

to

come in contact with groove

result.

GUIDE

\

W-1023

INSTALLATION

not reuse valve stem

be

withdrawn

stem.

Do

not

allow

or

seal

is

10-3

Valve Spring:

ends, distortion, and tension. check valve spring retainer for wear. Check for spring distortion by placing spring on a flat surface next to a square. Measure height of spring and rotate

square edge to measure distortion.

0.06

inch (1.5 mm) replace spring. Check spring tension

at the installed height for both the valve open and closed

position using an accurate valve spring tester. Replace

any valve spring that is weak, cracked, worn,

Valve

Rotators:

Check valve springs for cracks, worn

If

spring ends are worn,

it

against

If

distortion exceeds

or

distorted.

The P216, P218, and P220 engines use

Valve

deposits from valve seat Select proper puller size determined by inside diameter of valve seat On some pullers (Figure 4). Puller jaws must expand into cylinder block at the point where bottom of valve seat insert cylinder block. Position puller on valve seat and tighten hex nut Clamp cylinder block to a solid bench. Attach slide hammer to puller. Tighten hex nut between each blow with the slide hammer.

free-rotating intake and exhaust valves. while in the open position, the valves must rotate freely.

Seat

Removal:

use

a new seat as a guide

Remove carbon and combustion

to

adjust puller depth

rests

on

The P224 engine uses positive

type

valve rotators on the exhaust valves. When functioning properly, the valves are rotated a fraction of a turn each time they open.

open

While in the There is no easy way to determine

or

good

bad. Onan recommends that valve rotators

replaced at each major overhaul

carbon is noted

Valve

Seats:

loose,

cracked

position, the valves must rotate freely.

if

a valve. rotator is

or

if

a build up of

on

valve

face and valve seat.

Inspect valve seat inserts.

or

severely pitted, new ones must be

If

seats

be

are

installed. Remove valve seat inserts using a valve seat removal tool. are damaged

valve seat insert

or

worn

so

bores

in cylinder block

that

a press fit cannot be

If

obtained when installing new standard size valve seat inserts, the

seat

bores

USE

NEW

ADJUST

must

VALVE

PULLER

be

machined for an oversize

SEAT

TO

DEPTH

VALVE

INSERT

(USE

PROPER

K

THIS

BURRS

INSERTING

SEAT

DRIVER

TOOL)

SURFACE

BEFORE

SEAT

FIGURE

PULLER

JAWS

4.

VALVE

SEAT

REMOVAL

FIGURE

Valve

Seat

removed, clean out any carbon seat insert recess. hammer to install the insert (Figure seat insert

5.

INSERTING

Installatlon:

Use

a valve seat insert driver and

in

so

the

insert

NEW

VALVE

SEAT

After the old seat has been

or

metal burrs from the

5).

Drive the valve

enters the recess evenly.

Make certain that the valve seat insert rests solidly on the bottom, of the recess all the way around its circumference.

To assure a tight valve seat fit and eliminate the danger of seat loosening in the bore, valve seat must be staked.

,or

Insert valve: seat staker into valve seat

guide in

cylinder block. Using a lead hammer, strike the staking tool a sharp blow to wedge new valve seat securely in

will

place. It

be necessary to refinish valve seat inserts

before installing valves.

10-4

TAPPETS

Very little wear takes place on tappet diameters or in tappet bores.

If

the clearance between tappet and bore

in cylinder block exceeds specifications, replace the

tappet.

Inspect the tappet faces which contact camshaft

lobes

for roughness, scuffing, or concave wear. Replace any

If

worn tappets.

tappets are worn, inspect camshaft for

wear.

VALVE FACE AND SEAT GRINDING

Before installing new valves or previously used valves,

If

be

cleaned

used

44°.

it

and

If

inspect valve seats for proper valve seating. valves are reinstalled, the valve stems should and valve faces ground to their specified angles of

Refinish valve seats to a

45°

angle. When refacing valves and seats, remove all evidence of pitting and grooving. clean it up on the refacer wheel.

If

end

of

valve stem is pitted or worn, true

A

very light grind is

usually enough to square stem and remove any pits or

be

burrs. The valve guide should

thoroughly cleaned.

valve guide is worn, or valve is warped, the necessary

be

parts must

replaced.

Refinish valve faces to a machine. The first cut from valve face must

if

grinding. Check

removed.

If

check to see

there is an unevenness of metal being

only part of valve's face has been touched,

if

valve is properly seated in machine or

44°

angle on a valve refacing

be

a light

if

valve is warped, worn, or distorted. When cut is even around the whole valve face, keep grinding until com-

plete face is ground clean. Be sure the correct valve

is

face angle

maintained. When valve head is warped,

knife edge will be ground (Figure

7)

on part or all of the

a

head due to the large amount of metal that must be

Heavy

removed to completely reface valve.

valve heads are required for strength and good heat dissipation. Knife edges lead to breakage, burning, and pre-ignition

to

due

heat localizing on the edge.

Replace any valve that cannot be entirely refaced while keeping a good valve margin (Figure

worn, or damaged in any way. The amount

7)

or is warped,

of

grinding necessary to true a valve indicate whether valve head is worn or warped.

WARPED VALVE WITH KNIFE EDGE KNIFE EDGE

By

grinding the valve face and seat at slightly different angles, a fine line of contact on face and seat is obtained, eliminating the need to lap the seating sur-

faces. The one degree difference in angles is defined as

6).

the interference angle (Figure

The seat angle is greater than that of the valve face. This assures contact at the maximum diameter on valve seat seating surface.

FIGURE

6.

VALVE INTERFERENCE ANGLE

GOOD MARGIN

T

FIGURE

When new valve seats are installed, or previously used

seats reground, refinishing must seat grinder used according to the manufacturer's directions.

Valve seats should be ground with a and the width of the seat band should be

3/64

inch

(0.8

assure proper seating.

Place each valve in its proper location. Check each valve for a tight seat. Make several marks at regular intervals across the valve face using machinist's bluing.

if

Observe rotated part of a turn -against the seat. The valve seat

should contact the valve face evenly at all points. The

the marks rub off uniformly when the valve is

line of contact should be at the center of the valve face.

7.

VALVE

HEAD

MARGIN

be

done with a valve

45

to

1.2

mm) wide. Grind only enough to

degree stone

1/32

inch to

10-5

FLYWHEEL

GEAR

COVER

Removing the flywheel is a relatively simple process, but

be

the following procedure must damage to the gear case and possible injury to the operator.

1.

Turn the flywheel mounting screw outward about

two turns.

DO

not remove the screw com-

pletely

since

when

the

2.

not

held

wheel

can

cause

Install

will

a

puller

by

flysheel

cause

injury

the

bar

snaps

screw,

n

to

fly

to

the

on

the

off

operator.

flywheel

followed to avoid

it

loose.

spring

with

great

If

(Figure

acts as a restrainer

the

flywheel

action

force

in

which

8).

is

the

After removing the mounting screws, tap the gear cover gently with a

When installing the gear cover, make sure the pin in the gear cover engages the nylon lined (smooth) hole in the governor cup. Turn the governor cup

hole is at the three o’clock position.

grease

of The smooth side of the governor yoke must ride against the governor cup. Turn the governor arm and shaft clockwise until the gear cover is installed flush against the crankcase.

seal

(Figure

soft

faced hammer to loosen

Use

to assist in holding governor cup in position.

as

far as possible and hold in this position

Be

careful not to damage the gear cover oil

it.

so

the nylon lined

a small amount

9).

MOUNTING

FIGURE

3.

Turn the puller wheel snaps

flywheel

cover

pressure

4.

Unscrew the puller from the flywheel, remove the flywheel mounting screw and washer and pull the flywheel wheel.

against

is

die-cast material and

is

applied

off

A

bent

bar

loose

DO similar tool

the

BLOWER

on the shaft.

WHEEL

bolts

in, alternately, until the

not use

a

or

gear

case. The

will

in

this

manner.

the shaft. Take care not to drop the

or

broken

fin

will destroy

SCREW

PULLEY

screwdriver

pry

behind

gear

break

if

the

balance.

or

the

case

undue

ROTATE

CUP

SO

INTO

THE

BUSHING

GOVERNOR

FITS

METAL

IN

THE

CUP

I

FIGURE

9.

GOVERNOR

GEAR

COVER

CUP

GOVERNOR

IF

FEELER

ENTER

HOLE

BALL

ASSEMBLY

HAS

DIMENSION SHOWN

ON DRAWING WILL

AS

THE

INDICATED

CENTER

With the gear cover removed, the governor cup can

taken

off

SNAP

GOVERNOR CUP

GOVERNOR

FIGURE

CUP

GOVERNOR

be

after removing the snap ring from the camshaft center pin. Catch the flyballs while sliding the cup-off (Figure

Replace with a new part any flyball which is grooved has a flat spot; the

otherwise damaged; the gear/ spacer assembly

10).

ball

spacer

if

its arms are worn or

if

or

loose on gear hub, and the governor cup if the race surface is grooved

or

rough. The governor cup must

be

a freespinning fit on the camshaft center pin, but without any excessive play.

tilt

When installing the governor cup,

the engine

gear is up, put the flyballs in place (Figure

so

the

10),

and

install the cup and snap ring on the center pin.

The camshaft center pin extends out

3/4

inch

(1

9

mm)

from the end of the camshaft. This distance provides an

7/32

inch

(5.6

in-and-out travel distance of

governor cup, as illustrated.

Hold

the cup against the

mm) for the

flyballs when measuring. The camshaft center pin

be

cannot

pulled outward or removed without damage.

If the center pin extends out too far, the cup will not hold

less

than

the flyballs properly. If the distance is

(5.6

mm), the engine will race, especially at no load.

7/32”

Remove the center pin and press in a new pin.

BALL

CUP

GOVERNOR

DETAILS

BALL

GOVERNOR

TIMING GEARS

If

replacement of either the crankshaft gear camshaft gear becomes necessary, always install both gears new.

The camshaft and gear must

be

replaced as an assembly. Before removing the camshaft and gear assembly, remove the cylinder head and valve assemblies.

To remove the crankshaft gear, first remove the snap

ring and retainer washer, then attach the gear pulling ring using two

No.

10-32

screws (Figure the screws alternately until both are tight. Attach a gear puller to the puller ring and proceed to remove the gear.

“O”

Each timing gear is stamped with gear teeth must mesh

so

that these marks exactly

near the edge. The

coincide when the gears are installed in the engine.

When installing the camshaft gear and shaft assembly,

be sure the thrust washer is properly in place behind the camshaft gear. Then install the crankshaft retaining washer and lock ring.

11).

or

the

Tighten

CRANKSHAFT

GEAR PULLER

E MARKS

WHEN ING TIMING EARS

4.

Turn the crankshaft until the piston is at the bottom

its

stroke and remove the connecting

of the

rod

bearing cap from the

rod

and piston assembly out through the top cylinder using a hammer handle.

rod

nuts.

and push the

of

Do

not scratch the

Lift

rod

the

crankpin and cylinder wall when removing the piston and

5.

Mark each piston and

rod.

rod

assembly

so

they can

be

returned to their respective cylinders after overhaul. Keep connecting rod bearing caps with their respective

6.

Remove the piston rings from the piston with a

rods.

piston ring spreader (Figure 13). Remove the piston pin retainer and push the piston pin out

FIGURE

Observe

and connecting

1.

Drain oil.

2.

Remove the cylinder head and oil base pan from the

11.

TIMING GEAR REMOVAL AND INSTALLATION

PISTONS

the

following procedure when removing pistons

AND

CONNECTING

rods

from the engine.

RODS

engine.

3.

Remove the ridge from the top of each cylinder with

a ridge reamer before attempting piston removal

(Figure

12).

Forcing the piston from the cylinder before reaming may

cause

damage

to

the

piston lands and

break

rings.

FIGURE

7.

Remove dirt and deposits from the piston surfaces

13.

REMOVING

PISTON

RINGS

with an approved cleaning solvent Clean the piston

or

ring grooves with a groove cleaner piston ring filed to a sharp point (Figure

the end of a

14).

Care must be taken not to remove metal from the groove sides.

FIGURE

12.

REMOVING RIDGE

FROM

CYLINDER

pistions.

8.

Clean the connecting rods in solvent. Blow out all

There

materials will

cause

piston

damage.

passages with compressed air.

P224

Engines that have been filled with oversize pistons at the factory are identified by the letter

E

after the serial number. Number is stamped on the

cylinder block and on the unit nameplate.

0.005

inch

(0.1

3

mm)

10-8

FIGURE

15.

CHECKING

RING

SIDE

CLEARANCE

have deep nicks, signs of fractures, scored bores, or

bores

with dimensions which exceed that specified

DIMENSIONS AND CLEARANCES.

in

FIGURE

14.

PISTON

GROOVE

CLEANING

Follow the procedures given below when inspecting pistons and connecting

Piston

1.

Inspect

Inspection:

the

rods.

pistons for fractures at

the

lands, skirts and pin bosses. Check for wear at

the ring lands using a new ring and feeler gauge

15).

(Figure

side clearance reaches that specified in

Replace the piston when the

of

the top compression ring

DIMENSIONS AND

CLEARANCES.

2.

Replace pistons showing signs of scuffing, scoring, worn ring lands, fractures from preignition. Excessive piston

or

wear

damage

near the

edge of the top ring land indicates preignition.

ring

Measuring

1.

Proper

Pistons:

piston tolerances must

be

for satisfactory operation.

k

Refer to

DIMENSIONS AND CLEARANCES

determine where to measure piston to the total clearance follows specifications.

maintained

to

be

sure

Connecting

Replace connecting

Rod

Inspection:

rod

bolts

and nuts that have

damaged threads. Replace connecting

rods

that

10-9

FIGURE

16.

MEASURING PISTON CLEARANCE

Measuring

1.

Install the piston ring in the cylinder bore. Invert the piston and push the ring to the end of ring travel, about halfway into the bore, which trues the ring end gap. Check the gap with a feeler gauge (Figure

2.

The practice of filing ring ends to increase the end gap is not recommended.

does not meet specifications, check for the cor-

rect set of rings and the correct bore size.

cylinder bore that is size will reduce the end gap mm).

Piston Rings:

17).

0.001

If

the ring end gap

inch

(0.03

mm) under

0.003

inch

A

(0.08

After removing pistons, crankshaft, cylinder heads, etc.,

If

inspect block for cracks and wear.

it

viceable, prepare

1.

Scrape all old gasket material from block. Remove oil by-'pass to allow cleaning solution to contact inside of oil passages.

2.

Remove grease and scale from cylinder block by

agitating in a bath of commercial cleaning solution

or

hot soapy washing solution.

3.

Rinse block in clean hot water

solution.

When rebuilding the engine, thoroughly inspect block for any condition that would make it unfit for further use. This inspection must be made after all parts have been removed and block has been thoroughly cleaned and dried.

for cleaning as follows:

block is still ser-

to

remove cleaning

FIGURE

17.

POSITIONING

AND

MEASURING

OF

PISTON RING

OF

END

GAP

CYLINDER BLOCK

The cylinder block is the main support for all other basic

parts.

engine the block, assuring alignment of the crankshaft and cylinder

Crankshaft and camshaft are supported by

bores.

1.

Make

a

thorough check for cracks. Minute cracks

may

be

detected by coating the suspected area with

25

a mixture of light motor oil. Wipe the part dry and immediately apply

a

coating of zinc oxide (white lead) dissolved

in wood alcohol. coating will become discolored at the defective area. Always replace a cracked cylinder block.

2.

Inspect all machined surfaces and threaded holes.. Carefully remove any nicks surfaces. Clean out tapped holes and clean up any damaged threads.

3.

Check top and a feeler gauge.

Cylinder

scuffing, scratches, wear, and scoring. are scuffed, scratched, worn, rebored and honed for the next oversize piston.

When the appearance of cylinder bores is good and there are no scuff marks, check cylinder bore for wear

out

1.

Bore

of roundness as follows:

Check cylinder bore for taper, out of round, and wear with a cylinder bore gauge, telescopic gauge,

or

inside micrometer. These measurements should

be taken at four places: top and bottom of piston ring

travel, parallel and perpendicular to axis of crank-

shaft (Figure

percent kerosene and

If

cracks are present, the white

or

burrs from machined

of

block for flatness with a straight edge

Inspection:

18).

Inspect cylinder bores for

or

scored, they must be

75

percent

If

cylinder bores

or

10-10

2.

Record measurements taken at top and

piston travel as follows:

A

Measure and record as diameter (parallel to crankshaft) near the top of cylinder bore.

B.

Measure and record as diameter (parallel to crankshaft) at the bottom of piston travel.

“A

the cylinder bore

“B’

bottom

cylinder bore

of

RING

WEAR

AREA

C.

Measure and record as diameter (perpendicular to crankshaft) near the top of cylinder bore.

D.

Measure and record as diameter (perpendicular to crankshaft) at the bottom of piston travel.

E.

Reading reading cates cylinder taper.

If

cylinder taper exceeds that specified in

DIMENSIONS AND CLEARANCES

hone cylinder to the next oversize.

F.

Reading reading whether round exceeds that specified in

AND CLEARANCES

rebored and honed to the next oversize.

“A”

subtracted from reading

“C”

subtracted from reading

“A

compared to reading

“B”

compared to reading

or

not cylinder is out of round.

“C”

cylinder bore

“D”

cylinder bore

“B”

“D”

rebore and

“C“

“D

indicate

if

out of

DIMENSIONS

the cylinders must be

and

indi-

and

Reboring the Cylinder

Rebore and hone engine whenever cylinder bore worn, damaged, out of round,

A

exceeds specifications. resized to the smallest standard oversize diameter at

it

which should then should equal the standard diameter added to the oversize.

will-clean up. The final finish and bore diameters

be

obtained

If

it will produce

that

may

surface

should

who

are

be

careful

not

done only

in

worn cylinder bore should be

by

honing. Final bore diameter

boring

their

bar

clean up even when honed. Boring

by

qualified

work.

or

if

cylinder taper

is operated incorrectly,

a

rough cylinder

service

personnel

is

10-1

FIGURE

After boring to the correct oversize cylinder bore dimension piston and ring clearance should be

appropriate. There is no need to adjust and rings.

When reboring cylinders, take the following pre-

cautions:

1.

Make sure cutting tool is properly ground before using

2.

Be

free.

18.

METHODS

it.

sure top of engine block is smooth and deposit

OF

MEASURING

OF

A

CYLINDER

THE

BORE

or

1

DIAMETER

“fit” pistons

3.

Clean base of boring bar before bar is set up. Deposits under boring cylinder

4.

Make an initial rough cut, followed by a finish cut.

will be

distorted after boring.

bar

will

cause it to tilt and the

Then hone cylinder bore to the specified oversize. pistons with new rings may still be used.

Deglazing Cylinder

Deglaze the cylinder bores

and no wear

or

Bores

if

there are no scuff marks

out of round beyond specifications before installing new rings. Deglazing gives a fine finish, but does not enlarge cylinder diameter,

The reason for dealazing a cylinder is to provide cavities

Honing Cylinders (Using Precision

Hones)

to hold oil during piston ring break-in.

Refer to hone manufacturer's recommended grit size to

produce specified surface finish of

will

rough of a finish

wear out the rings and too smooth been dipped in clean, light engine oil.

Too

1.

Wipe cylinder bores with a clean cloth which has

20

to

40

RMS.

of a-finish can retard piston ring seating.

2.

Use a brush

1.

Position block solidly for either vertical

a

honing. Use either

drill press or heavy-duty drill bore.

which operates at approximately Follow hone manufacturer's instructions for the use Move deglazing tool up and down in cylinder

2.

or

of oil

lubricant on stones.

Do

or

horizontal tips to produce a crosshatch pattern in the cylinder

250

to

450

rpm.

not use lubricants

3. Use a slow

12

complete strokes) rapidly enough to obtain a

with a dry hone. crosshatch pattern (Figure Insert hone in bore and adjust stones to fit snugly to

3.

type

deglazing tool with coated bristle

speed

drill to drive the deglazing tool.

19).

the narrowest section. When adjusted correctly, the

or

hone should not shake

will

but

drag freely up and down when hone is not

chatter in cylinder bore,

running.

so

the original

(10

to

Connect drill to hone and start drill.

4.

high

spots,

which cause an increased drag on

Feel

out bore for

stones. Move hone up and down in bore with short

40

overlapping strokes about

times per minute.

Usually bottom of cylinder must be worked out first

As

because it is smaller.

cylinder takes a uniform diameter, move hone up and down all the way through cylinder

Check diameter of the cylinder regularly during

5.

A

honing.

dial bore gauge is the easiest method but

bore.

a telescoping gauge can be used. Check size at six places in bore: measure twice at top, middle and bottom at 90-degree angles.

Crosshatch formed by the stones should form an

6.

included angle of 23 degrees. This can be achieved

(250

to

450

by moving the rotating hone

40

down in cylinder bore about Clean cylinder bores thoroughly with soap, water

7.

A

and clean rags.

clean white rag should not

times per minute.

rpm) up and

become soiled on wall after cleaning is complete.

Do

not use a solvent

or

gasoline since they wash oil

from the walls but leave the metal particles.

Dry crankcase and coat it with oil.

8.

PRODUCECROSSHATCHSCRATCHES

FOR

FAST

RING

SEATING

FIGURE

19.

CROSSHATCHING

Never

cial cleaners

bores

after deglazing

will not remove abrasives from sives not removed rings, cylinder

from

walls,

and bearing surfaces

or

AVOID

THIS

FINISH

use

gasoline

or

commer-

to

clean cylinder

honing. These solvents

the

walls. Abra-

engine will rapidly

lubricated parts.

4.

Clean cylinder bore thoroughly with soap, water and clean rags. Continue cleaning until a clean white rag shows nodiscoloring when wiped through cylinder 'bore.

wear

of

all

10-12

CRANKSHAFT

Clean crankshaft thoroughly and inspect journals for scoring, chipping, cracking, or signs crankshaft has overheated, is scored, or excessively worn, reconditioning or replacement Examine bearing journals for cracks occurred.

Measure crankshaft main bearing and connecting rod journals at several places on their diameter roundness and taper.

of

overheating.

will

be required.

if

overheating has

to

check for

If

The only recommended method of reconditioning the

to

crankshaft is regrinding, as required

accommodate undersize bearings. Metalizing of bearing journals is not recommended.

If

regrinding of crankshaft journals is necessary, the

work should be done by a reputable machine shop that

to

has suitable equipment

handle precision work of this type. Undersize main bearings and connecting rodsare 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.

BEARINGS

With camshaft and crankshaft removed, use a micrometer to measure diameter of bearing journals. Use a dial bore gauge or a telescopic gauge and micrometer

if

to

clear-

avoid

to measure inside diameter of bearings. Refer

DIMENSION AND CLEARANCES

to determine

ances are within specifications. Any bearing that is scored: chipped, pitted or worn

beyond the specified limits must be replaced.

Removal of the camshaft bearings requires complete

or

disassembly of the engine. Use a press

a suitable driver to remove bearings. Support casting distortion and to avoid damaging the bearing bore during removal and installation.

Replacement camshaft bearings are precision type which do not require line reaming

or

line boring after installation. Clean outside of the bearing and bearing bore in the block. Before installing cam bearings use Locktite Bearing Mount on outside diameter of bearing.

to

Use a combination bearing driver

install bearings.

FRONT

PRESS

0.50

BEARING

(12.7

mm)

FIGURE

REAR

20.

CAMSHAFT

BEARING

BEARINGS

New crankshaft main bearings are precision type which do not require line reaming or line boring after installation. Use a press or a suitable driver to remove bearings. Support casting

avoid distortion and

to

avoid damaging the bearing bore during removal and installation.

Before installing main bearings, expand bearing bore by placing the casting in an oven heated practical, cool the precision bearing

to

200°F (94°C).

to

shrink it.

If

Before installing the front main bearing, use the towelette included with the bearing kit

to

clean the outside of the

bearing and bearing bore in the block.

Breathing vapor from towelette and

prolonged contact with skin can be

harmful.

Be

sure area is well ventilated.

Place the bearing on the crankcase over the bearing bore with the lubricating hole (front only) in the proper

to

position. Be sure

start the bearing straight. Press in the front bearing flush with the outside end of the bearing bore. Front cam bearing oil hole must line up

20).

with oiling hole in cylinder block (Figure the rear camshaft bearing

20).

(Figure

Lubricate bearing surfaces with oil after

to

the dimension shown

Press in

installing.

10-13

After

allowing

the Locktite from the small tube to the mating surfaces

three to four minutes for drying, apply

of the bearing and the bearing bore. Align the oil holes in the bearing with the oil holes in the bearing bore (Figure

22).

The oil passage should be at least half open.

Install the bearing flush with the block, using the

off

combination driver. Wipe bearing. Allow at least one hour for hardening at

excess Locktite around the

room

temperature.

FIGURE

21.

BEARINGS

FOR

REAR

BEARING PLATE

In the rear bearing plate, install the bearing flush to

1

/64

inch

(0.40

mm) below the end of the bore.

Be

sure to align the oil holes in the bearing with the oil holes in the bearing bore (Figure

open.

least half If

head of lock pin is damaged, use side cutters

Lubricate bearing after installation.

21).

The

oil

passage must be at

or

Easy Out tool to remove and install new pin. Oil grooves in thrust washers must face the crankshaft, and washers

on

must be flat (not bent). The two notches must

fit

over the

crankshaft (Figure

two

lock pins to prevent riding on the

21).

each washer

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

A

over the end of the crankshaft. thrust washer may hold

it

light film of oil on the

in place while installing bearing plate over crankshaft. Line up notches of thrust washer with lock pins before tightening end plate

or

lock pins will be damaged.

Engines shipped

washers and main bearings

from

the

factory

for

both front and

have separate thrust

rear

of engine. Front bearing replacement part is a one piece bearing (with attached thrust washer) as shown in

22.

Do

Figure

front

bearing.

not add an additional thrust washer to this

FROM

MAIN

CRANKSHAFT ENDPLAY

After

the

rear

bearing end' plate has been tightened,

using the torque recommended in

AND SPECIAL TOOLS,

23).

If

(Figure

there is too much endplay

check the crankshaft endplay

MENSIONS AND CLEARANCES

maximum endplay), remove the rear bearing end plate and add a Shim (Figure

21)

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.

ASSEMBLY TORQUES

(see

DI-

for

minimum and

between the thrust washer

FIGURE

23.

CRANKSHAFT

ENDPLAY

I

CHECKING CONNECTING

CLEARANCE

1.

Make certain that all

WITH

parts

ROD

BEARING

PLASTIGAUGE

are marked

or

identified

so they are installed in their original positions. Using a clean dry cloth, thoroughly clean all oil from

rod.

If

crankshaft journal and connecting

rod

bearing inserts are being replaced (P224 only),

rod

install them in

and cap.

connecting

2. Place a piece of correct size Plastigauge in the bearing cap the full width of the journal surface and

1/4

inch

(6.35

mm)

off

about

3.

Rotate the crankshaft about

center (Figure 24).

30

degrees from bottom

dead center and reinstall the bearing cap; tighten

rod

bolts

to the torque specified in

TORQUES

AND SPECIAL TOOLS.

ASSEMBLY

Do

not turn the

crankshaft.

4. Remove bearing cap. The flattened Plastigauge

be found adhering to either the bearing cap

will

or

FIGURE

24.

MEASURING BEARING CLEARANCE

crankshaft.

5.

Compare flattened Plastigauge with the graduations on Plastigauge envelope to determine clearance.

The bearing plate must

The number within the matching graduation on the seal (Figure 25). Drive the envelope indicates total clearance in millimeters thousandths of an inch. Before installing

or

seals,

multi-purpose grease. This will improve sealing. When, installing the gear cover

inward until

it

is

.645

gear cover. When installing the bearing plate oil

into the bearing plate bore shoulder in the plate bore. Use a seal expander

a

piece of

heavy

paper around the end of the crankshaft, when replacing the bearing plate to avoid damaging the seal. Remove the paper

MOUNTING FACE

OF

GEAR COVER

OIL

SEALS

be

removed to replace the oil

oil

seal out from the inside.

fill

the

space between lips with a

oil

seal, tap the

seal

inch (16.4 mm) from the front of the

seal,

to

bottom against the

as

soon

as

the plate is in place.

REAR BEARING PLATE

SURFACE SHOULD BE

CLEANED OF ALL OLD

SEALING

BEFORE INSTALLING

COMPOUND

tap the

or

place

seal

GEAR COVER

GEAR COVER OIL SEAL

'

FIGURE

GEAR COVER SURFACE

BE

SHOULD OLD SEALING COMPOUND

BEFORE INSTALLING SEAL

25.

CLEANED OF ALL

GEAR COVER AND

10-15

REAR

BEARING

PLATE

SEAL TO SHOULDER OF THE PLATE BORE

REAR BEARING PLATE

OIL

SEAL

OIL

SEALS

OR

PRESS

PISTON ASSEMBLY

1. Lubricate all parts with engine oil.

2. Position piston on its respective rod and install the pin.

3. Install the rings on the pistons starting with the oil

control ring (Figure 26). Use a piston ring spreader to prevent twisting or excessive expansion of the ring. Compression rings have a dot or the word

“top” on one side of the ring to indicate w,hich side faces the top of the piston. Unmarked piston rings can be installed either way. The oil control ring has an expander; install the expander first and then close until the expander ends butt. The joint should be 160 degrees from the gap of that ring.

P216, P216, P220 Install one fastener and tighten to 5 ft-lbs (7 Nm).

Repeat this for the other fastener. Tighten both

fasteners down to the torque specified in ASSEMBLY

TORQUES.

P224 Install and tighten the nuts evenly in steps, to the

torque specified in ASSEMBLY TORQUES.

OIL HOLE *

OR

COMPRESSION RINGS

OIL RING

\

EXPANDER

CT-1047

FIGURE 26. PISTON RINGS

INSTALLATION OF PISTON IN CYLINDER

1. Turn the crankshaft to position the number one rod bearing journal at the bottom of its stroke.

2. Lubricate the number one piston assembly and inside of the cylinder. Compress the rings with a ring compressor (Figure 27).

3. Position the piston and rod assembly in the cylinder block. Oil squirt hole of connecting rod must face camshaft.

* OIL HOLE NOT USED, LATER PRODUCTION

P216, P212, P222 CDNNECTING ROD P224 CONNECTIND

FIGURE 27. INSTALLING PISTON AND

CONNECTING ROD

CT-la7

ROD

CT-loa

5. Install the remaining piston and rod in the same manner. Crank the engine over by hand to see that all bearings are free.

6. Install the oil base with a new gasket.

4. Tap the piston down into the bore with the handle end of a hammer until the connecting rod is seated on the journal (Figure 27). Install the bearing cap on the rod.

7. Install the cylinder heads. See Cylinder Headsection for torques and torquing procedure.

6. Replace oil and break in engine.

lo-16

CYLINDER

HEADS

Remove the cylinder heads for carbon cleaning and gaskets rest. gasket change at intervals specified in the

Maintenance Schedule

(located in the Operator's

Periodic

Manual).

1.

Use a

1/2

inch

(13

mm) socket wrench to remove

cylinder head

(37°C)

100°

F

(37° C),

difficult ad

cylinder

2.

After removing heads, clean out

Be

careful not to damage where gaskets and can

bolts

or nuts. Lift heads

before removal.

the

gasket

to

remove

At temperatures

will

become

from

the

surface

head.

all

carbon deposits.

the

outer sealing edges

fit.

The

heads are made

be

damaged by careless handling.

off.

gummy

of

the

of

aluminum

above

ad

block

3.

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

P216,

P218,

P220

Installation

1.

Place a head gasket on the cylinder block and align

the holes in the gasket with the holes in the cylinder

block While holding the gasket against the cylinder head, carefully install the cylinder head on the engine.

through

not attempt to slide the head

the

gasket without the cylinder block behind

bolts

Do

it or the gasket may tear.

2.

Follow the head torque sequence shown

28.

Tighten all

(14

Nm), then to the torque specified in

TORQUES.

bolts

to 5 ft-lbs

(7

Recheck all head

Nm), then

bolts

in

Figure

10

ft-lbs

ASSEMBLY

for correct

torque.

NO.

1

CYLINDER

(LH)

FIGURE

28.

CYLINDER

10-1

HEAD

TORQUE SEQUENCE

7

NO.

2

CYLINDER

(RH)

P224

Installation

1.

Place a head gasket on the cylinder head and align the stud holes in the gasket with the stud holes in the cylinder head. While holding the gasket against the cylinder head, carefully install the cylinder head on the engine.

Do

not attempt to slide the gasket over the studs without the cylinder head behind it or the gasket may tear.

2.

Install a flat washer, nut on each of the top

two

compression washers, and

six

studs (Figure

29

for correct sequence). When properly installed, only the outside edges of the compression washers will be in contact with each other. Install a flat washer and nut on each of the four bottom studs.

HEAT

TREATED

NUTS

COMPRESSION

WASHERS

engine

damage.

3.

Follow the head torque sequence shown in Fig-

30.

ure

10

Tighten all nuts to 5 ft-lbs

ft-lbs

(14

ASSEMBLY

Nm), then to the torque specified in

TORQUES.

Recheck all nuts for correct

(7

Nm), then

torque.

FIGURE

6

LONG

29.

CYLINDER

STUDS/HEAD

HEAD

4

SHORT

WITH

COMPRESSION

STUDS/HEAD

WASHERS

NO.

1

CYLINDER

FIGURE

4.

Recheck torque when the engine has run a total of

50

hours.

30.

CYLINDER

HEAD

NO.

2 CYLINDER

TORQUE SEQUENCE

10-18

Product

information and specifications are

shown

herein

as

of the time

of

Wheel

Horse

I

right designs and standard equipment without notice and without incurring obligation.

Products,

to

change product specifications.

printing.

Inc.

reserves the

Toro 30620, 30798, 31-16O803, 31-16O804, 41-20OE02 Service Manual

Specifications and Main Features

Frequently Asked Questions

User Manual