Generac Power Systems TXP User Manual

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F-

ALTERNATOR

DIAGNOSTIC REPAIR

MANUAL

%■

Printed in U.S.A.

GENERAC

P.O. Box 8, Waukesha, Wisconsin 53186

50357

Engine Air Cleaner

Conduit Clamp

Button Plug

(Optional location of conduit clamp)

Oil Dipstick

Blower Shroud

Vibration Dampener

POSITIVE Battery

Cable Connection

Starter Solenoid

Figure 1. NOMENCLATURE

I Customer Wiring Connection

—■ Access Panel

Main Circuit Breaker

15 amp Fuse

Start/Stop Switch

NEGATIVE Battery Cable Connection

Solenoid Operated Fuel Shutoff Valve

Lowo7L¡^'""®'

Shutdown Switch

Customer Fuel Supply Line Connection

Fuel Pump

Oil Make Up Tank

(2 quart)

PART I

GENERAL

Section Title Page

1 Specifications.........................................................................................................................................................

Difference Data......................................................................................................................................................

Engine Lubrication................................................................................................................................................‘'■2

Electrical Test Specifications.............................................................................................................................. ■'•2

Torque Values........................................................................................................................................................‘'•2

Engine Specifications............................................................................................................................................

2 Wiring Diagram (Model 6931-0)............................................................................................................................2.1

Wiring Diagram......................................................................................................................................................2.2

Factory Equipped Customer Wiring Connections

TXP Reconnected for 120/240 Volt Output...........................................................................................................2.3

..........

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

2.3

SPECIFICATIONS

Model No.

Wattage Capacity Voltage Output Amperes

Frequency Phase(s) Voltage Regulation

Driven Speed Battery Charging

Amperes Gross weight (wet)

Engine Type ■ ■

Engine Horsepower

Bore

Stroke

6931-0 6931-1 6931-2

4500

120/240*

37.5 at 120 Volts - 18.75 at 240 Volts 60 Hz

1-Phase

120 Volts ( + 27o) AC at 60 Hertz

1800 rpm

0-10 Amperes at 12 Volts DC

215 Pounds

2-Cylinder, 4-Cycle, Aluminum

Approximately 10 at 1800 rpm

3.44 Inches (87.3 mm)

2.16 Inches (54.7 mm)

Displacement Valves

Stellite exhaust valves - Valve ro tators on exhaust valves

40 Cu, In, (656 cc)

Governed Speed 1800 rpm Air Cleaner Crankcase Oil

Capacity Oil Make-up System

Ignition System

Dry paper element, oil foam pre-cleaner

56 Ounces (3% Pints')

Maintains crankcase oil level at about

48 Ounces (3 Pints)

Solid state capacitor discharge type

Starting System 12 Volt DC electric (Ring Gear)

Cranking Current

Approximately 90 amperes nominal

*As shipped, alternator provides 120 volts AC only. Unit is

reconnectable to supply 120 and 240 volts AC. See Page 2,3.

DIFFERENCE DATA

Model 6931-0 - Rigid coupling between engine drive shaft and rotor Model 6931-1 - Added a flexible coupling between engine drive shaft

___________________

and rotor

_________________________________________________________

Model 6931-2 t New rotor with improved 4-pole laminations. New im

proved blower housing with heavier sheet metal. New

_________________

improved inertia ring.with increased mass.

______________________________

Issued 6-78

1.1

ENGINE LUBRICATION

Use any high quality detergent oil having a classification which inc

ludes ’’Service MS, SC, SD or SE”,

No special additives should be used.

ELECTRICAL TEST SPECIFICATIONS

RECOMMENDED SAE VISCOSITY GRADES

1 1

100

°C-30

TEMPERATURE RANGE ANTICIPATED BEFORE NEXT OIL CHANGE

-20 10 10

30 40

*If not available, a synthetic oil may be used

having — 5W-20, 5W-30 or 5W-40 viscosity.

COMPONENT

Stator Windings AC Power Windings AC Power Windings

Excitation Windings

Battery Charge

Windings

Rotor

Ignition Stator

Charge Coil

Trigger Coil

Ignition Stator Voltage Input to Printed

Circuit Board Fuel Pump DC Resistance

Spark Timing Choke Heater

TEST POINTS

Wire #11 - Wire #22 Wire #33 - Wire #44

White receptacle Pin #2 -Pin #6,

Wire #55 - Ground Wire #77 - Ground

Brush terminals or Slip Rings

Ignition Module Receptacle Pin

#2 - Ground

Ignition Module Receptacle Pin

#3 - Ground PGB Pin #4 - Ground

Fuel Pump terminal to ground

Wire #77 - Ground

TEST VALUE

0,42 Ohms 0,42 Ohms

2,30 Ohms

0,20 Ohms 0, 20 Olmns

13,00 Ohms

225.00 Ohms 4

6,00 Ohms

0.5-1.5 Volts 50,00 Ohms

26 BTDG

30.00 ohms

Sensing Transformer

Secondary Winding

Primary Winding

Field Boost Voltage

(While Cranking)

Wire #11 - Wire #22 White receptacle Pin #3 - #5

White receptacle Pin #4 - Ground

NOTE;-Either of two transformer makes may be used. The Wescoil transformer has a primary winding resistance of 745-825 Ohms and a secondary winding

resistance of 1603-2169 Ohms, The CoilTran transformer has a primary resis tance of 824-1114 Ohms and a secondary resistance of 1222-1654 Ohms.

1.2

See NOTE See NOTE

9 - 12 VDG

TORQUE VALUES

STANDARD TORQUE VALUES

Grade 2

BOLT SIZE

1/4-20 5 4 1/4-28 5/16-18 11 8 5/16-24

3/8-16 3/8-24 23 17 35 7/16-14 7/16-20

1/2-13 1/2-20 55 42 9/16-12 9/16-18 78

5/8-11 5/8-18

3/4-10

3/4-16

DRY LUB

6 5 10 7 12

13 10 20

32 36

49 70

105 165 125 180

1525

38 54 110 84

60 120 71

140 295

All Values in FOOT-POUNDS

TORQUE VALUES + 5 PER CENT

DRY

17 13 21 19 15 24

31 49 38

85 65 105

150 170 270 205

Grad

----------

LUB DRY

24 27

42 58

93 150 115

115 185 145 130 210 160

230

Grade 7

LUB

16 18

38 29 43 61 68

93 - 72

135 105

330 365

52 78

■ 80

250 280

Grade 8

DRY

8 9

27 49

105 120 90 155 170 132

210 165 240 185

375 420 320

■ LUB 12 9 14 24 18

44 70

11 21

34 38 54 60

120

290

7/8-9 200 7/8-14

1-8 1-14^ 340 260 680

SPECIAL TORQUES

Connecting Rod. Cylinder Head (Torque in staggered.sequence) Spark Plug.:.

Starter Motor Mounting Bolts..,i.............................................. .........................................160 In.-Lbs.

Engine Base

Sump (7 bolts)....

Crankcase Cover (7 bolts). Governor Lever Lock Nut...,.

Fan to Engine Shaft Capscrew (Grade 5)-(Apply Loc^Tite

601 to capscrew threads:) Flex Coupling to Rotor Hub Capscrews (Model 6931-2) -

(Apply LocTite 601 to capscrew, threads)................................................................. 19 Ft.-Lbs.

Flex Coupling to Fan Capscrews (Model 6931-2) - (Apply

LocTite 601 to capscrew threads).....................................................................................

.........

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

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

225 170 435 335 300

GRADE

BOLT HEAD

SYMBOL

.........

................................................ 200 In. -Lbs.

155 395 305 530

585 450

230

590 455

510

795 610

........................................................................••..190 In.-Lbs.

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

.(......I-............................................. 160 In.-Lbs.

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

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

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

..........

......................................................... 19 Ft.-Lbs.

..........

405

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

.......140 In.-Lbs.

605 670 515

905 695

..160 In.-Lbs.

300 In.-Lbs.

100 In.-Lbs.

19 Ft.-Lbs.

455

Issued 6-78 1»3

ENGINE SPECIFICATIONS

Spark Plug Gap

Crankshaft End Play..

Governed Idle Speed Adjustment...............................................................................................

Valve Clearance (with springs installed)................................................................Intake .005"-. 007"

Valve Seat Angle...........................................................................................................Intake - .30

Valve Seat.Width...............................................................................................

Valve Seat Margin................................................................................................Not less than 1/64'

Valve Clearance (springs not installed).,......

Crankshaft Reject Sizes.........................................................................................PTO Journal 1.376'

Cylinder Boi'e Standard Diameter

Ring Gap Reject Sizes (Top and center compression)......................................................................0.035'

Ring to Ring Groove Maximum Clearance

Maximum Piston Pin Out-of-Roundness....................................................................................,0,0005'

Crankpin Bearing Hole Rejection Size........................................................................................

Piston Pin Bearing Hole Rejection Size...;,.......................................................,,,,.,.,,.....0,802'

Camshaft Rejection Sizes (Gear and. Shaft Journals).......................................................................0,623'

Cylinder Bore Maximum Out-of-Roundness,

Cylinder Bore Oversizes when honing..........................................................

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

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

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

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

(oil Ring)................................................................................ .......0.045'

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

(Cam Lobes)

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

.........................................................................0,0025'

........

0.002"-0.008" 1400 rpm*

Exhaust .007"-.009"

Exhaust - 45

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

Intake .007"-.009'

0,010" above standard

0.020" above standard

0.030" above standard

3/64"- 1/16’

Exhaust ,009"-.Oil'

Crankpins 1.622'

..... 3.4375**

...1.252'

0.030"

0.007'

1.124'

*Adjust carburetor idle screw to 900 rpm

**Resize if worn 0.003" or more

1.4

Issued 6-78

(3 <

SCHEMATIC

CNJ

WIRING DIAGRAM

MODEL 6931 -0

legend

CH~ cnoke So/enold

CB— Circuit Breaker

D— Diode PP— Fuel. Pump FS— Fuel Solenoid HM— Hour Meter IM— Ignition Module IS— Ignition Stator

UT— Light LOS— Low Oil Switch

FCB— Printec? Circuit Board S— Starter SC— Starter Solenoid SW— Start-Stop Switch T— Transformer SP— Spark Plug VR— Voltage/Frequency Regulator

^ — Wire Nut

WIRING DIAGRAM

. d

WIRING DIAGRAM

■o

MODEL 6931-1

6931-2

)

Factory Equipped Customer Wiring Connections 120VoitsOniy

PROCEDURE

1. Disconnect wires No. 11 and No. 33 at main circuit breaker,

2. Disconnect wire No. Ti at main cir cuit breaker and discard.

3. Route wires No. 11 and 33 (discon nected from main circuit breaker) to

customer connection panel.

4. Connect customer wiring as shown to obtain both 120 and 240 volts A-C.

Main

Circuit

Breaker

Main Circuit Breaker is Not Connected

TXP RECONNECTED FOR 120/240 VOLT OUTPUT

Issued 3-78

Grounding Lug

PART II

TROUBLE DIAGNOSIS

Section Title Page

3 DIAGNOSTIC FLOW CHARTS

Engine Won’t Crank....................................................................................................................3.1

Engine Cranks, Won’t Start.........................................................................................................3.2

Engine Starts Hard, Runs Rough............................................................................................... 3.5

Switch Set to STOP, Engine Keeps Running..............................................................................3.7

A-C Voltage Low..........................................................................................................................3.8

A-C Power Low............................................................................................................................3.9

A-C Voltage High.........................................................................................................................3.9

No A-C Voltage..........................................................................................................................3.10

4 DIAGNOSTIC TESTS

Test 1-15 Amp Fuse..................................................................................................................4.1

Test 2 - Battery............................................................................................................................4.1

Test 3 - Start/Stop Switch............................................................................................................4.2

Test 4 - Starter Solenoid

Test 5 • Starter Motor...................................................................................................................4.4

Test 6 - Starter Bendix Gear........................................................................................................4.4

Test 7 - Starter Ring Gear............................................................................................................4.5

Test 8 - Check Spark...................................................................................................................4.5

Test 9 - Oil Make-up Tank...........................................................................................................4.6

Test 10 - Low Oil Switch..............................................................................................................4.6

Test 11 - Spark Plug....................................................................................................................4.7

Test 12 - Ignition Module.............................................................................................................4.7

Test 13 - Ignition Stator................................................................................................................4.8

Test 14 - ignition Coil...................................................................................................................4.8

Test 15 - Low Fuel Level..............................................................................................................4.9

Test 16 - No Fuel Flow...............................................................................................................4.10

Test 17 - 4 Amp Fuse.................................................................................................................4.10

Test 18 - Printed Circuit Board....................................................................................................4.11

Test 19- Fuel Filter.....................................................................................................................4.11

Test 20 - Fuel Shutoff Solenoid.................................................................................................4.12

Test 21 - Fuel Pump...................................................................................................................4.12

Test 22 - Check Installation........................................................................................................4.13

Test 23 - Carburetor...................................................................................................................4.14

Test 24 - Compression...............................................................................................................4.15

Test 25 - Head Gasket...............................................................................................................4.15

Test 26 - Valves.........................................................................................................................4.15

Test 27 - Rings...........................................................................................................................4.15

Test 28 - Cylinder.......................................................................................................................4.15

Test 30 - Choke..........................................................................................................................4.16

Test 31 - Pre-Choke...................................................................................................................4.17

Test 32 - Governor.....................................................................................................................4.17

Test 33 - Frequency...................................................................................................................4.18

Test 34 - Excitation Windings.....................................................................................................4.19

Test 35 - Carbon Buildup...........................................................................................................4.19

Test 36 - Cutput Voltage............................................................................................................4.19

Test 37 - Sensing Transformer

Test 38 - Main Circuit Breaker...................................................................................................4.21

Test 39 - Rotor...........................................................................................................................4.21

Test 40 - Field Boost..................................................................................................................4.22

Test 41 - Stator...........................................................................................................................4.23

Test 42 - Charging Cutput..........................................................................................................4.23

Test 43 - Circuit Breaker........................................................................................................... 4.24

Test 44 - Diodes D1 and D2.......................................................................................................4.24

Test 45 - Stator Battery Charge Windings..................................................................................4.25

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

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

'..............................................................................4.3

4.20

DIAGNOSTIG FLOW CHARTS 3

IMTRODUCTION

Use these FLOW CHARTS in conjunction with the detailed instructions for

each test in Section 4, Test numbers assigned In the FLOW CHART are id

entical to the test numbers assigned to specific tests in Section 4.

ENGINE WON’T CRANK

TEST 1 Page

15 Amp

Fuse

-------1-------

CHECKS

BAD

Replace

Fuse

TEST 6

Starter

Bendix Gear

«i^'^Retalner

Gear

CHECKS

BAD

Replace Bendix Gear

CHECKS'

GOOD

Page

4.4

Clutch

4.1

CHECKS

GOOD

CHECKS

■ GOOD

Test 7 Starter

Ring Gear

TEST 2 Page Battery

4.1

■ CHECKS GOOD

CHECKS

BAD

Recharge or Replace

TEST 5 Page STARTER

4.4

MOTOR

CHECKS

TEST 4 Starter Solenoid

GOOD

CHECKS

BAD

Replace Replace

Motor

Solenoid

Page

4.5

CHECKS

GOOD

BAD

TEST 3

Page

4.3

Start/Stop

Switch

CHECKS

BAD

Replace

Switch

^CHECKS

GOOD

Paee

4.2

Issued 3-78

CHECKS

BAD

3.1

ENGINE CRANKS , WON’T START

TEST 8 Page Check Spark

TEST 13

Ignition

Stator

4.5

Page

4.8

SPARK

•GOOD-

TEST 9 Oil Make-Up Tank

TEST 12

Ignition

Module

LOW

FILL TANK

Page

4.6

—GOOD

4.7

-------

-GOOD-

TEST 10 Low Oil

Switch 4.6

Page

BAD

REPAIR/ REPLACE

TEST 11

Spark

Plug

Page

4.7

GOOD

BAD

__L

Replace

Stator

TEST 14 Ignition Coil

GOOD

BAD

Replace

Module

[Replace

Coil

^jlF SPARK CHECKS GOOD,«

^ GO TO TEST 15 3

BAD

Replace

Plug

3.2

Issued 3-78

______________________

TEST 15 Low Fuel Level

To Vthicii Engintf

Page

To Alternitor Engine

4.9 — GOOD

TEST 16 No Fuel

Flow

Page

4.10

-BAD

TEST 17 4 Amp Fuse

Page

4.10

___________

TEST 20 Fuel

Shutoff Solenoid

Fuel ^ T«ik В

FILL TANK

S ^‘Pe

Д Nipple

^<^Anti ■ Siphon

Holes

LOW

Page

4.12

Pipe Cep

■GOOD.

TEST 19 Fuel Filter

”F“

GOOD

GO TO TEST 23

Page

4.11

-.GOOD

BAD

REPLACE

FUSE

TEST 18

Printed

Circuit Board

и ~ c=3 p|n

GOOD

Page

4.11

GOOD

REPLACE SOLENOID

TEST 21 Fuel Pump

BAD

Page.

4.12

GOOD.

■ BAD-

------------------

TEST 22 Check

Installation

,| REPLACE

BAD

REPLACE

FILTER

PUMP

—I—

BAD

REPLACE BOARD

Page

4.13

SIF TEST 1.6 IS GOOD,t 3 GO TO TEST 23 (

Issued 3-18 3.3

TEST 23

Carburetor

J / ^

Page

4.14

TEST 24

COMPRESSION

Page

4.15 BAD

TEST

GOOD

REPLACE GASKET

ADJUST

JETS

’

FLOAT SEAT

FLOAT LEVEL [

-BAD J replace

|. SEAT

hBAD-

■ CHANGE’

I adjust"

'I FLOAT.

-8^,TEST

REPIACE

CARBURETOR

TEST

,1 TEST

BAD

1 TEST

TEST 26

VALVES

-------

TEST.

TEST 28

CYLINDER t4.15

1 REPAIR 1

_Page_

Page

4.15

3.4

T.EST.

TEST 27

RINGS

Page

4.15

REPLACE I

GOOD

■ GOOD GOOD

-»‘I GO TO TEST 29§i

_ - --

_ - .

Issued 3-78

ENGINE STARTS HARD - RUNS ROUGH

Issued 6-78

3.5

TEST 15. Low Fuel Level

Page

4.9

■ GOOD

TEST 16 Page Fuel Flow

4.10

BAD

-GOOD-

TEST 23

Carburetor

Page

4.14

TEST-^

TEST-*-

FILL

TANK

REPLACE FILTER

REPLACE SOLENOID

TEST 19 Fuel Filter

TEST 20 Fuel

Shutoff Solenoid

Page

4.11

[adjustI Ijets

BAD^

REPLACE

CARBURETOR

-TEST

CHECK

REPLACE

SEAT

-TEST

Page

FLOAT VALVE

■ BAD*.

4.12

ADJUST FLOAT

-TEST,

1 ■

FLOAT LEVEL BAD-^

TEST-*-

3.6

REPLACE

PUMP

TEST 21 Fuel Pump

TEST 22 check

Installation

Pagè

4.12

Page

4.13

TEST 32 Gove mor

"^8 COMPRESSION "

Page

4.17

’change'

BAD

ADJUST

GOVERNOR

5 GO TO TEST 24 I

Issued 3-78

TEST 24

Compression

-—BAD

TEST 25 .

Head Gasket

Page

4,15

TEST 26 Valves

Page

4.15

BAD

REFI ACE GASKET

TEST

GOOD-

TEST 27 Rings

REELAGEl

R-INGS

BAD

GOOD

REPAIR

TEST

Page

4.15

BAD

Issued 6-78

TEST.

SWITCH SET TO STOP - ENGINE KEEPS RUNNING

TEST 3

Start/Stop Switch

Page

4.2

-BAD

I REPLACE

■ *" SWITCH

3.7

A-C VOLTAGE LOW

TEST 33 Check Frequency

BAD

TEST 32 Page Governor

Page

4.18

4.17

■ GOOD

¡testI

REPLACE STATOR

■ GOOD-

REPLACE VOLTAGE

REGULATOR

3.8

Issued 6-7 8

A-C POWER LOW

GOOD

TEST

NO .

■ CHANGE'

TEST 35

Page

Carbon Build-up

.4.19

DE-CARBONIZE

- HEAD

TEST

CHANGE

NO ‘

-CHANGE-

TEST 32

Governor

Page

4.17

sf^ ^

TEST

A-C VOLTAGE HIGH

NO A-C voltage,

TEST 36

Page Cheek Output

4.19

Voltage

GOOD

CHECK CUSTOMER

WIRING

TEST

TEST 38 Main

Circuit Breaker

BAD

REPLACE CIRCUIT BREAKER

~T~

TEST

Page

TEST 29 Rotor

Page

4.21

-GOOD■

BAD.

REPLACE

ROTOR

TEST

GOOD

TEST 41

Stator

REPLACE

STATOR

TEST.

Page

4.23

GOOD

CHECK WIRE

#14 '

[testI-

-BAD.

CHECK VOLTAGE

TO ROTOR

------------1------------BAD

_L_

CHECK #4 WIRE FOR 12 VOLTS'

-----------

----------------

GOOD

REPLACE PRINTED CIRCUIT

BOARD

3.10

Issued 3-78

DIAGNOSTIC TESTS

TEST 1 - l.S.AMP -FUSE

Remove and visually inspect the 15

amp fuse. A more thorough check may

be made with a Volt-Ohm-Milliammeter,

a_s foil o\vs :

1. Set VOM to ''+nC" and to ”Rxl” scale.

2. Connect test probes together and

’’Zero" the meter.

3. Touch test probes to the fuse

ends - meter needle should swing up

scale and indicate "Zero” ohms. If

needle does not move upscale, replace

the fuse.

RESULTS: 1.) Fuse tests bad.............Install new 15 Amp Fuse

2.) Fuse tests good

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

.....Continue tests in "Diagnostic

Flow Charts", Section 3

TEST 2 - BATTERY

Check battery condition, as well as the condition, cleanliness and sec

urity of battery cables and.connec

tions.

RESULTS: 1.) Battery, cables or connections

test bad.......................................

2.) Battery, cables and connections test good

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

.....Replace or repair the defec

tive component

Continue tests in "Diagnostic

Flow Charts", Section 3

Issued 3-78

4.1

TEST 3 -START - STOP SWITCH

/^5

Remove the 15 amp Fuse to disconn

ect the starting circuit. Then re

move 2 screws that retain the top

panel. Finally, remove the top panel.

RESULTS: 1.) Switch tests Bad..

2.) Switch tests Good.

Connect the VOM test probes to the Switch terminals as shown at right.

Hold Start./Stop Switch at START meter needle should not move.

Set the switches of a Volt-Ohm-

Milliammeter to and to ''Rxl"

scale. Connect meter test probes together and ”Zero" the meter. Connect the meter test.probes to the switch center and lower termi nals, as shown above. Meter needle

should not move. Hold Switch at

STA.RT position - meter needle

should, move upscale, to "zero”.

Hold switch at STOP - meter needle

should drop all the way downscale to "Infinity”.

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

Install a new switch Continue tests

Release the Switch to NEUTRAL po sition - the meter needle, should

not move. Hold the Switch at STOP - the. meter

needle should swing upscale and. ind'

icate "zero" ohms.

RESULTS: 1.) Switch tests Bad..

2.) Switch tests Good.

4.2

.Install a new Sta.rt/Stop Switch .Reconnect wires to Switch

Install top panel Install 15 Amp Fuse

Continue Tests

Issued 3-78

TES T 4 - STARTER SOLENOID

A.) Set the Start/Stop Switch to

START position and back to NEUTRAL

several times. An audible "click” should be heard as the solenoid actuates^

RESULTS: !.) Solenoid actuates, but

engine does not crank

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

Continue- ttst (Paragraph "B")

2.) Solenoid does not actuate,..Continue test (Paragraph "D")

B. ) Set VOM to "+DC" and to a scale greater than 12 Volts DC. Connect

the NEGATIVE (pr COMMON) test probe to. ground. Connect the POSITIVE (+) test probe to the battery cable connection on the starter solenoid. The

meter needle should indicate 12 volts DC.

RESULTS: 1.) Meter reads 12 VoltsContinue test (Paragraph "C")

2.) Meter indicates less

than 12 Volts..............................................Check for open or shorted wire

or loose connections between

battery and starter solenoid

C. ) Connect POSITIVE (+) meter probe to starter cable connection on

starter solenoid. Connect NEGATIVE (or COMMON) test probe to ground.

Hold Start/Stop Switch at START - meter should indicate 12 volts DC.

RESULTS: 1.) Meter does not indicate

12 Volts...............................................

..Install new starter solenoid

2.) Meter reads 12 Volts and

solenoid checks good.......Continue tests in "Diagnostic

Flow Charts", Section 3

D. ) Set VOM to "+DC" so that 12 Volts can be read. Connect, meter POS

ITIVE (+) probe to one of the small terminals on the starter solenoid.

Connect the remaining test probe to ground. Meter should read.12. Volts.

With NEGATIVE (or COMMON) test probe still connected to ground, conn

ect POSITIVE (+) test probe to the other small terminal. Meter should indicate 12 volts DC.

RESULTS.: 1.) Meter indicates 12. Volts

from BOTH small terminals

to ground

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

Continue tests in. "Diagnostic

Flow Charts", Section 3

Meter does NOT read 12

2.)

Volts.........................................................Retest battery, 15 Amp Fuse

and Start/Stop Switch. Wlien

sure that these components

are good, and 12 volts is not

obtained from both small ter minals, replace solenoid,

Issued 3-78

4.3

TEST 5 - STARTED MOTOR

A.) Set VOM to ”+DC" and to a high

enough DC volts scale to permit reading 12 volts. Connect the POS

ITIVE test probe to starter cable connection at the starter. Connect the NEGATIVE (or COMMON) test lead to ground,then hold Start/Stop

Switch at START. Starter should

run and meter should read 12 Volts.

RESULTS: 1.) Meter, indicates .12.. Volts,

■ but starter does not run...... Replace starter

2.) Starter runs........................................................Continue tests in "Diagnostic

Flow Charts", Section 3

RESULTS: 1.) Starter motor can be heard

running without load,

L'OOCAOOOOO .Continue checks in Paragraph

IfRtt

2.) Starter runs and cranks the engine

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

...Continue tests in. "Diagnostic

Flow Charts", Section 3

B. ) Remove starter. Inspect pinion gear for damage or excessive wear,

RESULTS: 1.) Starter pinion gear damaged,

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

2.) Starter Pinion gear is good,.................................................Continue test (Para

C. ) Without installing starter, connect starter cable from starter sol enoid to starter terminal post. Hold Start/Stop Switch at START. The

starter pinion gear should move outward on the clutch.

4.4

Replace

graph C)

Issued 3-78

RESULTS: 1.) Starter Pinion Gear does

not move outward.............................

2.) Pinion Gear does move out ward.’

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

TEST 7 - STARTER RING GEAR

A.) Inspect Starter Ring Gear for

damaged teeth.

Inspect helix on clutch for

freedom of operation. If sticking due to dirt, clean

entire starter drive. If

any parts are damaged or worn, replace.

.Continue tests in ’’Diagnos

tic Flow Charts", Section 3

RESULT: 1.^ Ring. Gear damaged,

2.) Ring Gear Good....

TEST 8 -CHECK SPARK

A.) Remove lead from one spark plug.

Connect the lead to Spark Plug test-

er,

plug tester clamp to a clean, paint-

free ground. Crank the engine - a sharp, "snappy" spark should be seen.

Repeat the test for the remaining

spark plug. _______________________

NEVER crank the engine, with a spark

plug or spark plug lead removed, un less the spark plug or.lead Is conn ected to a clean ground. Failure to ground the plug or lead can damag.e. the ignition coil. _______________________________

Part No. 41503. Attach the spark

^CAUTION

.Replace .Continue tests in "Diagnostic

Flow Chart", Section 3

RESULT: 1,)A sharp, snappy spark is NOT

observed...

2.)A sharp, snappy spark is ob served.

........

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

.....

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

Issued 3-78

.Continue tests in "Diagnostic

Flow Charts", Section 3

.Continue tests in "Diagnostic

Flow Charts", Section 3 4^5

TEST 9 -OIL MAKE-UP TANK

A.) Check Oil level in Oil Make-up Tank. If oil level is near OIL

CHANGE LEVEL arrows, refill tank

with same, type and grade of oil

used in engine crankcase.

RESULTS: 1.) Oil level LOW..

2.) Oil level.GOOD.

TEST 10 - LOW OIL SWITCH

A.) Remove one screw that retains the Low Oil Switch Cover. Move Cover

out of the way. Set VOM to "+DC" and to "Rxl" scale. Connect meter test probes and zero

the meter. Connect one meter test probe to lower left switch terminal and remaining probe to ground terminal (bottom of switch). With switch actuating lever DOWN (low oil condition), meter needle should swing up

scale to "Zero". If meter

A.) Remove one screw that retains the Low Oil Switch Cover. Move Cover

out of the way to.expose switch terminals. Set VOM to "+DC" and to "Rxl"

scale. Connect meter test probes and "zero" thé meter. Connect one test probe to lower left

switch terminal. Connect remain ing test probe to ground. With

switch actuating lever DOWN (low oil level), meter needle should

swing upscale to "zero". With switch actuating lever UP (norm al oil level), meter needle should drop all the way downscale to "infinity". MAKE SURE GROUND WIRE

BETWEEN SWITCH BOTTOM TERMINAL AND OIL FILLER. NECK BRACKET SCREW IS TIGHT.

.Refill tank .Continue tests in "Diagnostic

Flow Charts", Section 3

4.» 6

Issued 3-78

CAUTION

Before installing Low Oil Switch Cover, make sure the float arm is riding on top of the switch actuating lever. If float arm has dropped off of switch actuating lever, engine will not shut down when oil

level in tank is low.

RESULTS:.!.) Switch tests Bad

2.) Switch tests.Good...............Continue tests in "Diag

TEST 11 -SPARK PLUG

A,) Remove one spark plug. Connect

spark plug wire to plug. Ground spark plug against engine. Hold

Start/Stop Switch at START and ob

serve spark plug. A sharp, snappy spark should be seen. Repeat test for second spark plug.

CAUTION

NEVER crank engine with a spark

plug or spark plug wire removed,

unless the spark plug or wire is

connected to a clean ground. Failure to ground the plug or lead can damage the Ignition coil,

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

Replace Switch

nostic Flow Charts", Sec

tion 3

RESULTS: 1.) Sharp, snappy spark is

NOT observed.

2.) Sharp, snappy spark IS observed,.

Test 12 - IGNITION MODULE “

A.) Unplug the Ignition Module

from its receptacle. Inspect the

connector pins in the module and

module receptacle - make sure

the pins are not bent or pushed in. Install a new (or "shop") ig

nition module and check for norm

al spark.

RESULTS: 1.) Normal "hot" sparking...................................................Install a new Ignition

2.) Normal sparking NOT observed.... Continue tests in"Diagnos-

.........

....

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

......

.................................................................. .Continue tests in

.Replace spark plug

"Diagnostic* Flow Charts", Section 3

Module, continue tests

tic Flow Charts", Section 3

Issued 3-78

TEST 13 - IGNITION STATOR

A.) Remove the wire nut from Wire No. 20.at the Low Oil Switch. Dis

connect the wire, to prevent inter action. Then proceed a.s. follows:

a. Set VOM to ”Rxl00" and to ”+DC”.

Zero the meter. Connect one meter

^ A test probe to Pin No. 2 of the Ig-

cJwoj/nition Module receptacle. Connect

the second test probe to ground.

^v> Meter needle, should swing upscale

R^-^j^nd read appro.ximately 225 Ohms

(+10'^°)* This is the Ignition State

Charge Coil resistance. RESULTS: 1.) Tests Bad

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

2.) Tests Good

Reconnect Wire No. 20 at the

fore proceeding to next test

TEST 14 - IGNITION COIL

Set

A.)

’+DC", then zero the meter. Conn

to "Rxl" scale and to

VOM

ect one meter test probe to Pin 4 of the Ignition Module receptacle.

Connect the remaining test probe

to Ignition Module receptacle Pin

1. Meter needle should swing up scale and indicate the Ignition

Coil primary winding resistance

(about 0.5 Ohms).

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

b. S'et the VOM to ”+DC" and to ’’Rxl”

scale. Again zero the meter. Connect

one meter test probe to Ignition

Module receptacle Pin No. 3, and the

second probe to ground. Meter needle should swing upscale and,read approx

imately 6 Ohms. This is the Ignition Stator Trigger Coil resistance.

...........

,Install new Ignition Stator .Continue tests in "Diagnostic

Flow Chart", section 3

Low Oil Switch and retain with wire nut be-

, Also install Ignition Module,.

4.8

Issued 3-78

RESULTS: 1.) Checks BAD................................................Replace Ignition Coil

2.) Checks Good...........................................Continue with Paragraph "B"

B.) Set VOM to "RxlOO" scale and zero

the meter. Unplug both spark plug

wires from Ignition Coil, and in

sert the two meter test probes as shown. Meter needle should indicate secondary winding resistance, about 6500 ohms.

RESULTS: 1.) Checks Bad.............Replace. Ignition Coil

2.) Checks Good...

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

Continue with Paragraph "C"

C.) Set VOM to ”Rxl0,000" scale and zero the meter. Connect one

meter test probe to Ignition Coil as in Paragraph ”B”, but conn

ect the second probe to ground. Meter needle shonld not swing

upscale (infinity).

RESULTS: 1.) Meter swings upscale.... Replace Ignition Coil

TEST

2.) Meter does not move

15 -LOW FUEL LEVEL

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

A.) Check fuel level in gas. tank. The vehicle engine fuel pickup

tube in the tank, is usually sev

eral inches longer than the alter

nator pickup tube. This means that,

even if adequate fuel is available for vehicle engine operation, the fuel may be below the alternator fuel pickup tube.

Continue with tests in

"Diagnostic Flow Charts",

Section 3

To Vehicle

Engine

Fuel

Tankik p

Installation Of Second

Fuel Pick Up Tube In

Tank Outlet.

To Alternator Engine

Pipe Nipple

Variable

Potentiometer ^

\ Anti-Siphon

■^Holes

3 in.

♦

Pipe Cap

To Alternator

Engine

3 In

Fuel Pickup/Float

Assembly

To Vehicle Engine

Fuel Gauge Connection

Fuel

Quantity

Float

Issued 3-78

4.9

TEST 16 -NO FUEL FLOW

At carburetor inlet, spread clamp

and slide it down the fuel inlet hose. Disconnect the hose from in

let fitting - BE CAREFUL NOT TO

BREAK THE FITTING. Hold open end

of fuel hose over a suitable con

tainer. Hold Start/Stop Switch,at

START to crank engine. Check for

fuel flow from fuel inlet hose.

DANGER

A’

Gasoline vapors are highly flammable and. explosive. Do not Jbermit

smoking, open flame or sparks in the vicinity while checking for

fuel flow.

RESULTS: 1.) Fuel.. Flow Bad.............................................

2.) Fuel Flow Good

TEST 17-4 AMP FUSE

A.) Remove 15 Amp fuse to disconn

ect starting, circuit. Remove the

2 screws that retain the top panel.

Remove the top panel.

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

B.) Remove the 4 Amp Fuse from the Printed Circuit Board. Check visu ally for an open fuse element. Set VOM to "+DC" and to "Rxl" scale. Zero the meter. Connect meter test probes to both ends of fuse. Meter needle should swing upscale and in dicate "zero".

Continue tests in "Diagnostic

Flow Charts", Section 3

Continue tests in "Diagnostic

Flow Charts", Section 3

RESULTS: 1.) Fuse checks Good

2.) Fuse checks Bad..................................Replace Fuse

4.10

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

Continue tests in

Diagnostic Flow Charts" Section 3

Issued 3-78

TEST 18 - PRINTED CIRCUIT BOARD

A.) Depress locking tangs of Print

ed Circuit Board connector plug and disconnect plug from its receptacle.

On the connector plug, locate Pin #

4 to which Wire #20 attaches. Set

the VOM switches to ’.’AC" and to 2,5 Volts, Connect one VOM test probe to Connector plug Pin #4 and the other

test probe to ground. Crank the eng

ine - Tneter needle should swing up

scale and indicate approximately 0,5 volts AC (pulsing voltage),

RESULTS: 1,) Meter indicates 0,5 Volts

2,) Meter does not indicate,,

0,5 volts

B.) Plug printed circuit board

connector plug in. Locate Wire

#14 connection at terminal strip.

Set VOM to "+DC" and to ''50V' scale. Connect POSITIVE (+) meter test probe to terminal strip wire

#14 connection and other test

probe to ground. Crank the engine.

Meter should indicate battery vol

tage (9-12 volts DC),

RESULTS: 1,) Meter indicated 12 volts,

2,) Meter did NOT indicate,,.

12 volts

TEST 19 - FUEL FILTER

,Go to Paragraph ”B” .Check Wire #20 between Print

ed Circuit Board and Terminal Strip, and between Terminal Strip and Ignition Module for open or shorted condition.

• Continue tests in ’’Diagnostic Flow Charts”, Section 3 Check Wire. #14 between Terminal

Strip and Printed Circuit Board for open or shorted condition. If not open or shorted, replace

Printed Circuit Board,

Remove and replace the In-Line Fuel Filter, Make sure arrow on

Fuel Filter points towards the

solenoid-operated Fuel Shutoff

Valve, Repeat TEST 16 on Page

4.10 (No Fuel Flow).

Issued 3-78

RESULTS: 1.) Fuel Flow Good,

engine still won't start

2. ) Fuel Flow Bad

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

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

3. ) Fuel Flow Good and engine

starts..........................Repair completed,

TEST 20 - FUEL SHUTOFF SOLENOID

A.) Disconnect Fuel Shutoff Solenoid Wire #14 at the Fuel Pump terminal. Crank the engine for 2 or 3 seconds,

then touch the terminal end of Wire

#14 to the Fuel Pump terminal. Fuel

Shutoff Solenoid should actuate and sound of Fuel Pump should change not iceably.

RESULTS; 1.) Fuel Shutoff Solenoid did

not actuate

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

2.) Fuel Shutoff Solenoid actuated

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

Go to TEST 23 Go to TEST 20

dis-

continue tests

•Replace Fuel Shutoff Solenoid

.Continue tests in "Diagnostic

Flow Charts", Section 3

TEST 21 - FUEL PUMP

A.) Disconnect BOTH Wires #14 at the

Fuel Pump terminal. Set VOM to "+DC" and to "Rxl" scale. Zero the meter.

Connect one meter test probe to the

Fuel Pump connection terminal and the remaining test probe to ground. Meter

needle should swing upscale and read

approximately 50 Ohms.

RESULTS: 1») Pump tests Good

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

Go to-Paragraph "B"

2.) Pump tests Bad^..............................................Replace Fuel Pump

B.) Reconnect both Wires #14 to Fuel Pump connection terminal,

engine and listen for sound of fuel pump.

RESULTS: 1.) Pump does not pulse.......................................Go to Paragraph "C"

2.) Pump pulses normally

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

..Continue tests in "Diagnostic

Flow Charts", Section 3

Crank the

4.12

Issued 3-78

•C.) Disconnect Wire #14 at Fuel Pump terminal. Set VOM to ”+DC” and to 50

Volt scale. Connect the POSITIVE (+)

meter test probe to the terminal end

of Wire #14. Connect the COMMON test probe to ground. Crank the engine -

meter needle should deflect upscale

and indicate battery voltage (about

12 volts DC).

RESULTS: 1.) Meter does NOT read 12 volts............................................*...Go to Paragraph ”D’

2.) Meter indicates 12 volts, but pump

does not pulse when Wire #14 is

connected to its terminal.'......................................................Replace Fuel Pump

D,) Check Wire #14, between the Fuel Pump and terminal strip in control panel, for open or shorted condition.

RESULTS: 1.) Wire #14 checks Good

2.) Wire #14 checks Bad..................................................Repair/Replace Wire #14

TEST 22 -CHECK INSTALLATION

Does the installation include a second in-line fuel filter? If so,, check

the filter for clogging. If a shutoff valve is installed in the fuel supply line, make sure the valve is open. Finally, make sure the air in let opening in the door is large enough. An insufficient supply of cool ing air will result in high compartment temperatures and possible fuel line vapor lock. Refer to INSTALLATION MANUAL, RECREATIONAL VEHICLE ALT ERNATORS (Part No. 49204).

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

Continue tests in”Diagnos-

Issued 3-78

tic Flow Charts", Section 3

4.13

TEST 23 - CARBURETOR

Ad just Jets: Turn Needle Valve

clockwise until it just closes DO NOT TURN IN TOO FAR, OR JET

MAY BE DAMAGED. Then open needle

valve l\ turns (counterclockwise).

Close Idle Valve in same manner,

then open 1^ turns. This initial adjustment will permit the engine to be started and warmed up.

With engine running, hold the throttle lever against the Idle Stop. Set

the Idle Speed Adjusting Screw to obtain 1400 rpm. Turn Idle Valve SLOW

LY clockwise to obtain 1400 rpm, 93 volts AC, or 46 Hz. Then turn Idle Valve SLOWLY clockwise (lean mixture) until engine misses or engine

speed slows. Finally, turn Idle Valve one-half turn counterclockwise.

Hold throttle lever against idle

stop and turn Idle Speed Adjust

ing Screw to obtain 900 rpm (30

Hertz or 60 Volts a-c). Then bend Governed Idle Tab (see illustrat

ion at right) to obtain 1400 rpm

(93 Volts a-c or 46 Hertz).

___________________

NOTE

Governed idle must be adjusted

for proper operation. The smaller spring keeps the engine on govern

nor, even at idle speed. Idle

speed should not be lower then 1100 rpm, 73 volts or 37 Hz.

Release throttle lever and let'engine accelerate to governed speed. Apply a load to the alternator, between'3000 and 4500 watts. Turn Needle valve SLOWLY clockwise (lean mixture) until voltage reading

starts to drop off. Then turn Needle Valve counterclockwise until the highest voltage reading is obtained. When the highest voltage is obtained, turn the Needle Valve counterclockwise an additional

1/8 of a turn.

Check Float Valve and Seat; Refer to engine section of this Manual

for procedures. Inspect float valve and its seat for damage, dirt

or wear.

Check Float Level; Refer to engine section of this Manual for pro

cedures .

4.14

Issued, 3-78

TEST 24 - COMPRESSION

A. ) Use a standard compression gauge.

Insert end of gauge into spark plug

hole. Open throttle wide open and

crank the engine. Repeat compression check for second cylinder. There

should be no more than a 25 per cent difference in compression between the two cylinders. A greater pressure difference indicates loss of compress ion.

COMPRESSION GAUGE

SPARK PLUG

REMOVED

RESULTS: 1.) Compression Low

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

Paragraph ’’B”

2.) Compression Good....Go to

Test 29

B. ) Squirt a few drops of oil into the

spark plug opening of one cylinder. Repeat compression Test of Paragraph ’’A” above. If compression is higher than was obtained in "A”, RING or CYL INDER wear is indicated. If little or

no difference in compression is noted,

compression loss is due to a leaking

HEAD GASKET, FAULTY VALVES, etc.

Repeat Paragraph "B" for second cylinder,

RESULTS: 1.) Compression Increased,.Go

to Test 27 and 28

2.) No increase

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

to Tests 25 and 26

TEST 25 HEAD GASKET

Go to

Refer to ENGINE REPAIR section of this Manual.

TEST 26 VALVES

Refer to ENGINE REPAIR section of this Manual.

TEST 27 RINGS Refer to ENGINE REPAIR section of this Manual.

TEST 28 CYLINDER

Refer to ENGINE REPAIR section of this Manual.

Issued 3-78

4.15

TEST 30 CHOKE

A.) Hold the Start/Stop Switch at

START position and crank engine. While the engine is cranking, the Choke Solenoid should pulse., the choke from a ”No-Choke” to a ’’Choke’’ position, at a rate dep

endent on ambient temperature.

RESULTS: 1.) Choke Movement Good

2.) Choke does not move

B.) Inspect the Choke Assembly and Linkage for binding caused by im

proper choke support alignment, dirt, etcJ Push the Choke back and

forth with your finger - no mechanical binding or sticking should be

observed.

RESULTS; 1.) Choke is Binding.........................................Adjust or clean choke linkage

Choke moves freely

C.) Loosen the two solenoid adjusting screws. Adjust solenoid axial

movement so that, with the carburetor choke valve closed, the choke

solenoid plunger is bottomed. Tighten the two adjusting screws, and check again for correct choke action.

RESULTS; 1.) Solenoid pulls in normally

2.) Solenoid does not operate normally...Go to Paragraph ”D”

D.) A small 2-wire disconnect is located adjacent to the Choke assembly.

Wire #90, from the Printed Circuit Board to the Choke Solenoid, and

Wire #14, from the Printed Circuit Board to the Choke Bi-Metal, can be

disconnected here. The following test is a check of the Printed Circuit

Board, which governs Choke pulsing action.,

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

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

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

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

Go to Paragraph ”C” •

Go to Test 31 Go to Paragraph ”B”

Go to Test 31

CAUTION

The VOM positive (+) test probe MUST be connected to the Wire #90

pin on the FEMALE half of the disconnect. This is wire #90 from the Printed Circuit Board. DO NOT connect the test probe to the male half of the disconnect (wire. #90 from the Choke Solenoid). Wire #

90, from the Choke Solenoid to the male half of the disconnect, is HOT while the engine is being cranked. Connection of the VOM to the Wire #90 MALE disconnect pin will seriously damage the meter as

soon as the engine is cranked.

4.16

Issued 6-78

Unplug the mating halves of the

small disconnect. Locate the male and female pins that connect Wire

#90 from the Choke SOLENOID (NOT

from the Choke Bi-Metal). Set the

VOM to ”+.DC” and to ”Rxl” scale,

then zero the meter. Connect the

POSITIVE (+) meter test probe to the FEMALE Wire #90 pin, NOT TO

THE MALE WIRE #90 PIN. Connect the

common (-) test probe to ground. Crank the engine. Meter needle

should swing upscale, then drop

downscale in a pulsing cycle.

RESULTS: 1.) Meter needle does NOT move

2.) Check is Good, but on sub sequent tests Choke does not

operate normally

TEST 31 PRE-CHOKE

A.) With the Choke Bi-Metal cold

(ambient temperature)., the carbu retor Choke Valve should be app roximately 1/8 inch away from its

vertical position, and towards a

CHOKE position. If necessary, loosen the Bi-Metal, adjusting

screws and move the Bi-Metal to

obtain this setting. This is the "Pre-Choke” position.

TEST 32 GOVERNOR

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

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

..Replace Printed Circuit Board

Replace Choke Assembly

A.) Adjust Carburetor jets and Governed Idle as outlined in Test 23,

CARBURETOR. These adjustments must be completed before attempting to

adjust the Governor.

RESULTS: 1.) Problem, is corrected.....................................................................Test Completed

2.) Engine "hunts" ,and/or AC Voltage

or Frequency is incorrect...........................................Go to Paragraph "B"

Issued 6-78

4.17

B.) Loosen Governor Lever Nut, Push Governor Lever all the way

counterclockwise to open thrott le wide open. Hold the Governor Lever in this position, then ro tate the Governor shaft all the way counterclockwise, as far as it will go. Tighten the Governor Lever Nut to 100 inch-pounds.

RESULTS: 1.) Engine runs normal, provides

62 Hz at "No-Load"..............................................................Test Completed

2.) Engine "hunts" and/or AC Voltage

or Frequency is incorrect......................................................Go to Paragraph "C"

C.) With engine running, turn

Governor Adjusting Nut to ob

tain 62 Hz at "No-Load".

Governor tab should be bent to

apply slight tension to governed idle spring at 1860 rpm (62 Hz or 124 volts), with no electrical loads applied. Spring should be

loose when loads are applied.

Governed

IdleTang

Governor Shaft

Governor Lever Nut Governor

Lever

;

Idle Speed

Adjustment Screw

Carburetor Body

Throttle Lever/

Governor Adjustincj Nut

NOTE

The Governed Idle spring, prevents engine speed surging and "hunting" during "No-Load" conditions. When an electrical load is applied, the spring will normally become loose and ineffective.

TEST 33 FREQUENCY

A.) Use an accurate Frequency Meter to check alternator output frequen

cy. The Model 5515 Load Bank is equipped with a frequency meter, as well as provisions for reading voltage and amperage. Frequency should be 63

Hz (63 cps) at "no-load". With an electrical, load applied, frequency

should be 59-63 Hz and stable. (All mechanical governors have a normal

ffspeed" fluctuation, which is the reaction time of the governor.)

RESULTS: 1.) Frequency checks Bad

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

Continue tests in "Diagnostic

Flow Charts", Section 3

2.) Fi'equency Checks Good

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

Continue tests in "Diagnostic

Flow Charts", Section 3

4.18

Issued 6-78

TEST 34 - EXCITATION WINDINGS

A. .) Remove Control Panel top cover.

Locate the white connector plug at the rear of the panel. Unplug the connector from its receptacle. Set VOM to '’+DC” and to ”Rxl" scale,

then zero the meter. Connect one meter test probe to receptacle pin #2. Connect the second test probe

to receptacle pin #6. Meter needle

should swing upscale and indicate about 1.8 to 2.5.ohms. This is the resistance of the stator excitation winding..

RESULTS: 1.), Windings check Bad.

2.) Windings check Good

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

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

.....................................Continue tests in

''Diagnostic Flow Charts", Section 3

B. ) Set the. meter swLtches ..to "+DC!' and to "Rxl0,000" scale. Zero the

meter. Connect one teat, probe to white receptacle pin #2, and the other

test probe to ground. Meter needle should not move.

RESULTS: 1.) Meter needle swings upscale

2.) Meter needle does not move

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

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

...Replace stator

"Diagnostic Flow Charts", Section 3

TEST 35 - CARBON BUILDUP

A.) Excessive carbo.n buildup in the engine combustion chamber can ser

iously affect engine power. Carbon deposits should be removed every 500 hours of operation, or whenever the cylinder heads are removed. If engines are run at a steady load, it may be necessary to remove carbon

more often. Refer to ENGINE REPAIR section of this Manual for cylinder

head removal and installation procedures. When reinstalling cylinder heads, bolts must be installed in the proper location on the head and

the cylinder head must.be properly torqued.

Replace Stator

Continue tests in

TEST 36 - OUTPUT VOLTAGE

A,.) Use an accurate voltmeter or

the Model 5515 Load Bank to check output voltage. When using a volt

meter, connect one meter test

probe to alternator output lead T1 and the remaining test probe to 2 output leads T2. Voltage should he. approximatel.y 125 volts at "no-load",

and.115 - 125 volts AC under load.If

voltage checks good, check frequency.

Issued 6-78

4.19

TEST 37 - SENSING TRANSFORMER

Either of 2 Sensing Transformers may be used. I4ien checking Transform er windings for an open condition, resistance readings obtained should

be as shown in the following CHART:

TRANSFORMER

MAKE WesCoil CoilTran

RESIS.TANCE [in OHMS)

Primary Secondary

745-825

824-1114

1603 - 2169 1222 - 1654

A.) Remove wire nuts that retain wires #11 and #22, between the Transformer and Voltage Regulator

Disconnect the wires. Set VOM to ”+DC’ and to ’’RxlOO” scale. Zero the meter. Connect one meter test probe to Wire #11, and the second test probe to Wire #22. Meter needle should swing upscale and indicate resistance for SECONDARY

Sensing Transformer With Wires To Secondary Winding

winding.

RESULTS: 1.) Checks Good.

Continue tes.ts in "Diagnos

tic Flow Charts", Section 3

2,) Checks Bad..

.Replace Sensing Transformer

B. ) Set VOM to "+DC" and to "Rxl0,000" scale. Zero the meter. Connect

one meter test probe to Wire #11. Connect the second test probe to

Ground. Meter needle should NOT move. Any needle movement indicates a

shorted condition.

White ' Pin No. 5

Receptacle Pins No. 3 and No. 5 to Primary

Winding of Transformer

---------------

RESULTS: 1.) Tests Good....

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

Continue tests in "Diag

nostic Flow Charts"

2.) Tests Bad...................................................................Replace Transformer

C. ) Unplug the white connector plug from its receptacle. Set the VOM

to "+DC" and to "RxlOO" scale. Zero the meter. Connect one meter test

probe to White receptacle Pin #3. Connect the second test probe to white receptacle Pin #5. Meter needle should swing upscale and indic ate resistance shown in CHART for PRIMARY winding,

RESULTS: 1.) Tests Good......................................................Continue tests in "Diagnostic

Flow Charts", Section 3

2.) Tests Bad

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

Replace Transformer

D. ) Set VOM to "+DC" and to "Rxl0,000" scade. Zero the meter. Connect one meter test probe to white receptacle Pin #3. Connect the remain

ing test probe to Ground. .Meter.needle should not move.Any movement of the needle indicates a shorted condition.

RESULTS. 1.) Tests Good......................................................Continue tests in "Diagnostic

Flow Charts", Section 3

2.) Tests Bad

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

Replace Transformer

4o20 Issued 6-78

TEST 38 - MAIN CIRCUIT BREAKER

NOTE

If the alternator has. been re.eonnected to provide a dual voltage

of 120 and 240 volts, the Main Circuit Breaker will be disconnec

ted from the circuit. See WIRING DIAGRAMS, Section 2.

A.) Disconnect wires from Main

Circuit Breaker terminals ”A" and ”B", to prevent interaction. Set VOM to "-)-DC" and to "Rxl" scale. Zero the meter. Connect one meter

test probe to Terminal ”A" and

one probe to Terminal . ”B’.', With

the Circuit Breaker ON, meter

needle should swing upscale and

indicate ZERO ohms. With Breaker

OFF, meter needle, should drop all

the way downscale to !.'Infinity”,

TEST 39 - ROTOR

A.) Use a ^ inch nut driver to re move the No. 8-32 screw that reta

ins the Brush Inspection Cover to

the Rear Bearing Carrier. Remove

the Brush Inspection Cover, Set a VOM to "Rxl" scale and to "+DC". Zero the meter. Connect one meter test probe to the brush terminal

furthest from the Brush Inspection

Cover opening. Connect the . s.e-cond

test probe to Ground, Meter needle should swing upscale and indicate

approximately 13 Ohms. (+10 %). •

■ RESULTS: 1.) Tests Good...,,

2.) Tests Bad,

B.) Use a \ inch nut. driver to re move the Brush terminal screws, as

well as the Brush Holder reta.Lning screws. With VOM set to. "+DG" and to "Rxl" scale, repeat the test of

Paragraph "A" directl.y on the Rotor

Slip Rings, Meter needle should, swing

upscale and indicate, approximately 13

Ohms (+ 10%).

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

.Continue tests in "Diagnostic

Flow Charts", Section 3

.Go to Paragraph "B"

Issued 6-78

4.21

RESULTS: 1.) Tests Good

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

Go to Paragraph ’’C”

2.) Tests Bad.............................................Replace Rotor

C.) Inspect Brushes and Slip Rings. Replace Brushes if cracked, broken or less than 5-/16 inch long. If Slip Rings aire dirty or tarnished,

clean with fine sandpaper. DO NOT USE EMERY CLOTH.Then repeat Test "A”.

RESULTS: 1.) Tests Good............................................Continue Tests in "Diagnostic Flow

Chart", Section 3

2.) Tests Bad

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

Replace Rotor Assembly

TEST 40 - FIELD BOOST

A,) Unplug the Ignition Module

from its receptacle to prevent the engine from starting. At the rear

Pin No. 4

of the control panel (on the panel floor), disconnect the white conn ector plug from its receptacle. Set the VOM to "+DC" and to a scale that will permit 12 volts to be read. Connect the Positive (+) test probe to white receptacle Pin #4 and the COMMON test probe to Ground. Crank the engine. Meter should indi

White

Receptacle

Field Boost:

From PCB Pin No. 2, to

White Receptacle Pin No. 4, to Brushes & Slip Rings, To Rotor Windings.

cate about 9-12 volts DC. Reconn ect the white connector plug before proceeding.

RESULTS: 1.) Checks Good

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

Continue|with "Diagnostic Flow

Charts", Section 3

2.) Checks Bad

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

Go to Paragraph "B"

B.) Unplug the connector plug from the Printed Circuit Board and from

the white.receptacle. Set VOM to "+DC" and to "Rxl" scale. Zero the

meter. Connect one meter test probe to printed circuit board connect

or plug (Pin #2). Connect the second test probe to white receptacle connector plug (Pin #4). Meter needle should swing all the way upscale to "zero

RESULTS; 1.) Wire #4 checks good..............................................Replace Printed Circuit

Board

2.) Wire #4 checks Bad............Repair/replace Wire #4

RESULTS: 1.) Checks Good, but checked Bad

in Paragraph "A"

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

Check Wire #4, between the

.Printed Circuit Board and

white receptacle

2.) Checks Bad.

.Replace Printed Circuit

Board

4.22 Issued 6-78

TEST 41 - STATOR

A.) Disconnect Wires #11 and #33

from the Main Circuit Breaker, Dis

connect two Wires #T2 from customer wiring. The two wires #T2 are also labelled.#22 and #44. Set VOM to ''+DC” and to "Rxl" scale. Zero the

meter. Connect meter test probes to Wires #11 and #22, and. observe the

reading. Then connect test probes to Wires #33 and #44 and observe the reading. In each case, the meter

needle should swing upscale, to app

roximately 0,42'Ohms.

RESULTS: 1.) Tests indicate open.

2.) Tests Good.

B.) Set VOM to ”+DC” and to ”Rxl0,000!’ scale. Zero the meter. Connect one meter test probe to Wire. #11..Connect the second test probe to Ground. Observe meter. Then connect one test probe to Wire #33 and the other test probe to Ground, In each case, the meter needle, must not

move (Infinity). Any movement of the meter needle indicates a "shorted”

condition.

RESULTS : 1.) Tests indicate "sho.rt"..............................

2.) Tests Good

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

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

.Disassemble, alternator. Test

stator with VOM and with an Insulation Breakdown Tester.

Replace, if defective.

,Go to Paragraph "B"

Di.sas,semble. alternator. Test

stator with VOM and with an

Insulation Breakdown Tester,

Replace if defective,

...Continue tests in "Diagnost

ic Flow Charts", Section 3

Battery Charge Tests

TEST 42 - CHARGING OUTPUT

A.) Disconnect Wire #66 at the

control panel Terminal Strip. Then connect an Ammeter in series with the disconnected Wire #66 and the Terminal Strip connection. Start the alternator. The Ammeter, should indicate an output, dependent upon battery condition.

Issued 6-78

RESULTS: 1.) Ammeter indicates discharge or

no output............................................................................

2.) Ammeter indicates a charge

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

Go to Test 43 Discontinue tests

Disconnect Ammeter from circuit and reconnect Wire #66 to Terminal

Strip before proceeding.

TEST 43 - CIRCUIT BREAKER

A.) Disconnect Wires #77 and #78

from the Circuit Breaker. . Set VOM to ”+DC” and to "Rxl*' scale, and zero the meter. Connect meter test probes to Circuit Breaker terminal studs. Meter needle should swing upscale to "zero".

RESULTS: 1.) Checks Good........................................................I....G0 to Test 44

2«) Checks Bad,

................................................................Replace Circuit Breaker

Battery Charge Circuit Breaker

TEST 44 - DIODES D1 & D2

A.) Disconnect Wire #78 at the battery charge circuit breaker.

Set VOM to "+DC" and to "Rxl"

scale, then zero the meter. Connect the Positive (+) »test probe to Wire #78 from Diode D2. Connect the COMMON (-) test probe to Ground. Meter, needle

should not move. Set meter to "-DC" (or reverse the test prob

es). Meter needle should swing

(Looking Rearward From Front of Control Panel)

upscale to some raid-scale read

ing (approximately 7 - 1.2. Ohms).

RESULTS: 1.) Tests Good.

.Reconnect Wire #78. to. circuit

Breaker, go to Paragraph "B"

2,). Tests Bad,.

.Replace Diode D2

B.) Remove wire nut and disconnect Wire #55, near Diode. Dl. Set VOM

to "+DC" and to "Rxl" scale. Zero, the mater. 'Connect the. Positive ( + ) test probe to Wire #55 from Diode Dl. Connect the COMMON (-) test

probe to Ground. Meter needle should.not move. Set VOM to "-DC" (or

reverse the test probes). Meter needle should swing upscale, to some

mid-scale reading (approximately 7- 12 Ohms).

Control Panel Top

4.24

Issued 6-78

RESULTS; 1.) Tests Good......................................Reconnect Wire #55, retain with

wire nut. Go to Test 45

2.) Tests Bad........................................

Replace Diode Dl

TEST 45 -STATOR BATTERY CHARGE WINDINGS

A.) Remove the 15 Amp Fuse. Discon nect Wire #77 from Battery Charge

Circuit Breaker, Remove wire nut

from the Wire #55 connection, near Diode Dl, then disconnect the wires. Set VOM to ”+DC” and to "Rxl” scale. Zero the meter. Connect one meter test probe to Wire #55, Connect the other test probe to Wire #77, Meter

Battery

Charge Circuj^ Breaker

needle should swing upscale and in

dicate approximately 0,20 Ohms.

Wire No. 78

RESULTS

1, ) Tests Good,

2. ) Tests Bad..

.Go to Paragraph ’’B” .Replace Stator

B.) With 15 Amp Fuse still removed, set VOM to "+DC" and to *'RxlO,000"

scale. Zero the meter. Connect one meter test probe to Wire #55, and the other test probe to Ground, Meter needle should not move (infinity),

RESULTS; 1,) Meter needle moved upscale

2,) Meter needle did not move,,,

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

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

Wire No. 77

^ Nut

Wire

No 55

Shorted condition indi

cated, replace Stator

.Checks Good

Issued 6-78

4.25

PART III

ALTERNATOR REPAIR

Section Title Page

5 CONTROL PANEL

Customer Wiring Connections................................................................................................5.1

Voltage Regulator................................................................................................................... 5.1

Printed Circuit Board............................................................................................................... 5.3

Diodes D1 and D2...................................................................................................................5.4

Other Components..................................................................................................................5.4

Panel removal......................................................................................................................... 5.4

6 ALTERNATOR

Rear Bearing Carrier...............................................................................................................6.1

Stator ......................................................................................................................................6.2

Rotor...................................................................................................................................... 6.3

Flexible Coupling.....................................................................................................................6.4

Fan ..........................................................................................................................................6.5

Engine Adapter/Ignition Stator.............................................................................................. 6.6

7 REASSEMBLY

Engine Adapter/Ignition Stator................................................................................................7.1

Fan .........................................................................................................................................7.1

Flex Coupling/Rotor................................................................................................................7.1

Stator ......................................................................................................................................7.2

Rear Bearing Carrier............................................................................................................... 7.2

Control Panel...........................................................................................................................7.3

CONTROL PANEL

CUSTOMER WIRING CONNECTIONS

Customer wiring connections for

120 volts only are shown at right.

A 3-wire cable should be used.

Connect two alternator T2 wires to

one cable wire. Connect one alter

nator Tl'wire to a second cable

wire. The third cable wire should'

be connected to the grounding lug,

as shown at right.

NOTE

Panel output wiring can be reconn

ected to supply a dual voltage of 120/240 volts.. See Section 2. A 4-

wire cable is required.when supply

ing dual voltage.

__________

VOLTAGE REGULATOR

The Voltage Regulator used on the TXP provides a constant voltage to

frequency ratio of 2 to 1, That is, when alternator frequency is 60 Hz, voltage output will be 120 volts a-c ( + 27o). If frequency should drop to 55 Hz, output voltage would also drop, to about 110 volts a-c.

The Voltage Regulator Assembly for

the Model 6931-1 TXP is shown at right. Be sure to check the wiring

diagram for the specific model in volved. The following CHART lists Regulator wires and their function.

------T3--------Connector

Wire #

6 #6 . .

11 22

Pin Function

#1 #2

DC Current from (-) brush and slip ring AC Current from excitation windings DC Current to (+) brush and slip ring AC.Current from excitation windings

,#3

120 volt sensing from Sensing Transformer 120 volt sensing from sensing Transformer

Issued 3-78

5.1

VOLTAGE REGULATOR ADJUSTMENT

The Voltage Regulator is adjusted at the factory and normally requires no additional adjustment. If the engine is running at 62 Hz "No-Load"

and voltage readings are incorrect, the Regulator may be adjusted. An accurate Frequency Meter and Voltmeter are required to adjust the Reg

ulator. The Model 5515 Load Bank.provides both these instruments. The

following procedure covers use of the Load Bank for Regulator adjust

ment.

1. Connect 3-wire cord set (Part

No. 27821) to alternator output wires as shown above. Plug the

connector plug into the 120 volt,

3-prong connector plug on the

Load Bank. Set ALL Load Bank Hea

ter element switches to OFF. Set

Ammeter Hi-Lo Range Selector

Switch to 0-50 AMPS. MAKE SURE

THE LOAD BANK HEATER ELEMENT COV

ER IS OPEN.

2. Adjust carburetor jets and go verned idle as outlined in Test

23, Page 4.14,

3. Adjust Governor as outlined in

Test 32, Page 4.18 and 4.19.

5.2

Issued 3-78

PRINTED CfRCUIT BOARD

The Printed Circuit Board provides the. necessary components for;

1. Control of those functions■ required.for. engine starting, runn ing, and stopping. These functions include:

a. Energizing the Fuel Shutoff Solenoid open and closed, as needed

b. Turning the electric fuel pump ON and OFF

c. Energizing the Choke Heater d. Controlling Choke Solenoid action

2, Controlling current flow to the .Field .Boost circuit during a start.

This current is delivered..across the brushes and slip rings, to en

sure the presence of a magnetic field, around ..the Rotor during a start.

Thus, it is never necessary to energize the field,, since it is energ

ized during every start. The illustration at right shows

the Printed Circuit Board comp

onents that can be tested, adj usted, or replaced. Maintenance

is limited to (a) replacement of

the 4 Amp Fuse, (b) adjustment of the Choke Adjustment potenti ometer, or (c) replacement of the entire Printed Circuit Board.

The Printed Circuit Board recept acle and its mating connector are

shown at right. Notice the funct

ions of each pin in the connector and receptacle.

Wire

No. 1

2 3 4 20

5 6

7 8

No.

15 12 VOC

.— —

Nominal

Value

6-12 VDC

0 OR 12 VDC

/Pi 11 Qinn)

\ r u 1 o H 1 u 1

0 • 3 VAC

12 VDC

•0-

0 OR 12 VDC

(Pulsing)

Function Battery Voltage to PCB

Field Boost current to Rotor Choke Solenoid Ignition Stator output (Turns PCB

on during start) Not Used To Fuel Pump, Fuel Shutoff Solenoid, and Choke Heater

PCB Ground

Choke Solenoid

The Choke Adjustment Potentiometer

can be used to increase.. o.r decrease choke time. To INCREASE, choke time, turn the adjustment screw clockwise. To decrease choke time (or increase "no-choke" time"), turn the slotted adjustment counterclockwise.

n__n—TL-n__n

I .(i) (D © fp|

a 0

^£0 Or

0) 3

•pi:

Receptacle (viewed From Pin End)

Choke Time

Potentiometer

□ □ □ [Il

□ □ □ □

Connector Plug (Viewed From Wire End)

CAUTION

Be careful not to force the slotted adjustment past its stops.

_______________________

Issued 3-78

5.3

DIODES D1 & D2

Diodes Dl and D2 are a part of the battery charging circuit. They fun ction to convert the a-c output of the battery Charge windings, to dir

ect current (d-c). Battery.charge , circuit checks are outlined in Tests 42 through 45, Pages 4.24 through

4,26, When replacing a defective di ode, bleed off excessive .heat by

means of a heat sink - dfodes are ex

tremely sensitive to. heat.

OTHER COMPONENTS

other Control Panel components are

shown at right. These include (1) a 40 Amp Main Circuit Breaker, (2) a 15 Amp Fuse, (3) a Start/Stop Switch, (4) battery Charge Circuit

Breaker, (5) Sensing Transformer,

and (6) Terminal Strip, Refer to Sections 2 and 3 for troubleshoot ing and testing of these, components,

Refer to the Wiring Diagram for *

each speci.fic alternator model when reconnecting components.

PANEL REMOVAL

1, At front of alternator, locate the large wire bundle from control panel. Disconnect all wires from this wire bundle, as follows:

(a) Wire #14 at fuel pump

(b) Wire #20 to Low Oil Switch (c) Two Wires #15 at Starter Sol

enoid

(d) Wire #13 at Starter Solenoid (e) Wire #17 at Starter Solenoid (f) Wire #91 at Starter Solenoid

5,4

Issued 3-78

2, At rear of Panel, (a.) disconn

ect spark plug wires from Ignition

Coil, (b) disconnect the wire con nectors A and B,. and (c.) cut the

tie wrap that holds Wires #2 and

#6 to the stator bolt.

3, Remove the Panel top cover.

4. Remove wire nuts and disconnect wires #11 and #22 to Sensing Tran

sformer, as well as Wire #55 to Diode Dl. Disconnect wire #66 at terminal strip. Disconnect wire #

77 at battery charge circuit brea ker. Disconnect wires #11 and #33

from main circuit breaker and pull

through the snap bushing.' Remove wire nuts from two. wires #T2 and pull through snap bushing. Pull all

wires through snap bushing at rear floor of panel.

Issued 3-78

5. At the rear exterior floor of the control.panel, locate wires # 1, #2, #4 and #6 that connect into

the white receptacle. Use a small

screwdriver or pen knife to "un lock” each female pin from its. re ceptacle slot, while carefully pul ling down on each wire. Remove all four wires from the white receptac le.

5.5

6, Use a \ inch nut driver to rem

ove brush inspection cover screw. Remove brush inspection cover. Use a % inch nut driver to remove the 2 screws that retain the brush

holder. Cut the tie wrap that ret

ains the brush wires to the rear

bearing carrier.

7. Use a 7/16 inch socket to remove

the 4 bolts that retain the control panel ho the stator can. Lift stra

ight up and remove the entire cont rol panel.

5.6

Issued 3-78

ALTERNATOR

rear bearing carrier

REMOVAL

1. Remove Control Panel as outlined in Section 5.

■Xtic.-;

i!.

- ■ 1

2. Remove the Fuel Shutoff Solenoid Clamp screw. Tape o.r cover the open end of the Fuel Filter to prevent entry of dirt. Lay the Filter, Sol enoid and hoses out of the way.

4. Use a 7/16 inch socket to remove the 4 stator bolts. Use a wood or fiber mallet to tap each projecting

corner of the Rear Bearing Carrier.

When Rear Bearing Carrier Is free

of the Rotor bearing, slide the wire

bundle through the snap bushing and

remove the Rear Bearing Carrier.

3. Use a k inch nut driver to remove

the 3 screws that retain the Fan Guard. Remove the Fan Guard.

INSPECTION

1. Check closely for cracks, or other damage.

2. Check condition of snap bushing. Replace, if damaged.

3. Inspect threaded holes for condition of threads, damage, etc. Repair

or retap, as required.

Issued 3-78

6.1

4. Inspect rotor bearing mating

surface on Rear Bearing. Carrier. Replace Rear Bearing Carrier if damaged, or worn exces.sively. Use an inside micrometer to mea

sure bearing insert inside diam

eter. Inside diameter of insert

must be 1.3749 - 1.3755 inches.

]yia,ximum out-of-roundness must

not exceed 0.003 inch. Replace

Rear Bearing.-Carrier, if these

limits are exceeded.

STATOR

REMOVAL

1. Remove the stator-to-vibration dampener bolts, hex nuts, and lockwashers, using a 9/16 inch socket.

Bolt heads are below the slide pan. Rest the engine adapter housing on a block of wood, then completely remove all vibration dampener com

ponents.

2. Tap stator can free of engine

adapter. Carefully remove the stat or can, along with the Alternator

Adapter Housing. If necessary to

remove the Alternator Adapter Hous

ing from the Stator can, place re

assembly alignment marks on Housing and Stator can, then tap Housing free of Stator can.

INSPECTION

1. Inspect Stator can. Alternator Adapter Housing, and Stator windings for obvious damage. Replace, any component that appears to be damaged. If required. Alternator Adapter Housing can be replaced. Replace the

entire stator can as an assembly.

2. Carefully inspect stator wiring for damage. Repair or replace de fective wiring, as required.

2 Issued 3-78

3. Set VOM to "+DC" and to "Rxl” scale. Zero the meter. Connect the

meter test probes to stator wires

listed in CHART below. Meter needle should sx^dng upscale and indicate resistances as listed in CHART, If

meter needle does not swing upscale,

the winding being tested Ls ’’open”,

and stator should be replaced.

4. Use an INSULATION BREAKDOWN tester to test stator windings for

defective insulation. Follow the

tester manufacturer’s instructions carefully. Test each winding at

2000. volts, from the. winding to ground, and at 1500 volts between isolated windings.

NAME OF WINDING

Power Power

Excitation

Battery Charge

ROTOR

1. Insert a screwdriver through engine adapter housing cooling air slots and between fan blades

to stop rotor from turning. Rem

ove 3 bolts that retain the flex- .

ible coupling to the fan. (LOC-TITE was applied to threads of these bokts during assembly.)Remove the Rotor and Flexible Coupling.

WIRE,NO. READING

11 to 22 33 to 44

2 to 6’

55 to 77

"0742 '

0.42

2.30

0.20

REMOVAL

Issued 3-78

6. 3

INSPECTION

1. Brush Holder & Brushes - The Brush Holder was removed along with the Control Panel, and left attached to Control Panel wiring. Inspect

Brush Holder for obvious damage, cracks, etc. Replace, if damaged. In

spect brushes carefully. Replace if cracked, damaged or less than 5/16 inch long.

2* Rotor Bearing - Check bearing for freedom of rotation. Bearing must spin freely on shaft. If bearing must, be replaced, use a bearing pull

er to remove, then press a new bearing over shaft.

3. Slip Rings - Inspect Slip Rings. If dirty, dull or tarnished, clean

until shiney with fine sandpaper..DO NOT USE EMERY CLOTH.

4. Rotor Windings ■ ? Inspect entire rotor for obvious damage. Set, VOM to "+DC" and to "Rxl” scale, then zero the meter. Hold the Positive

(+) meter test probe into contact with slip ring ring nearest the rotor bearing. Hold the second test probe against the other slip ring. Meter needle should swing upscale and indicate approximately 13 Ohms. If the

meter does not swing upscale, rotor,windings are "open”. An INSULATION BREAKDOWN TESTER.may be used to test the rotor windings. BE SURE TO

FOLLOW THE TESTER MANUFACTURER'S INSTRUCTIONS. DO NOT CONNECT TESTER PROBES ACROSS THE SLIP RINGS. DO NOT EXCEED TESTER SETTING OF 500 VOLTS.

FLEXIBLE COUPLING

1. The Flexible Coupling is ret

ained to the Rotor with 3 bolts and flatwashers. If necessary to

remove the Flexible Coupling, re move the 3 bolts and washers. (LOC-

TITE was applied to threads of the bolts during assembly.)

INSPECTION'

The Flexible Coupling should be rejected if bent, cut, gouged, or other wise damaged. Any scratch, other than a surface scratch, should be cause

for rejection. The coupling, must be perfectly flat. Especially note the condition of coupling mounting holes. Any damage caused by improper in stallation of washers is cause for rejection. Any wear or out-of-round-

ness of mounting holes is .also cause for rejection. FOLLOW INSTRUCTIONS

IN THIS MANUAL CAREFULLY FOR INSTALLATION OF'THE FLEXIBLE COUPLING.

6.4

Issued 3-78

FAN

REMOVAL

;| r 'j®SsiSte«№'

1. Prevent the Fan from turning.

2. Use a ^ inch socket with breaksr bar to remove Fan Bolt. Remove Fan Bolt, washer and Belleville washer.

2. Install a bolt into threaded

center of engine shaft. Install

3 bolts into flexible coupling

mounting holes on Fan. Install a

puller as shown. Tighten puller,

then strike with mallet sharply.

Alternately tighten puller and

strike puller end, until Fan is free of tapered engine shaft.

INSPECTION

“t

*5M,

■.'_. «miBrtoliKSSSii'

: -V. .

r ; .ki'.

■/'L'itei.,!''''M' -,v ... •

:W-- '

V4-'5?lai,'

. C.,..r ..y‘ -

&• j'

V>''‘

1. Thoroughly de-grease and clean

Fan and Ring Gear. Inspect close ly for cracks, or other damage.

2. Check condition of all thread

ed holes.

3. Check fan special key and key

way, as well as keyway on tapered

engine shaft. Replace key if worn or damaged. Replace any part with

a worn keyway.

Issued 3-78

4. Check Ring Gear, To replace,

remove 3 screws and elastic stop nuts. Clean Ring Gear to Fan mating surfaces thoroughly before

installing new Ring Gear, New

screws and locknuts are shipped with Ring Gear,

5, Magnet is located opposite the counterweight. Replace Fan is it has shifted, or is damaged. North pole of a magnetic compass must attract pole of magnet indicated above,

6.5

ENGINE ADAPTER

IGNITION STATOR

1, The Engine Adapter Housing is retained to the engine by four 5/8-

16 X 1 inch long button head screws.

To remove Engine Adapter Housing,

remove these screws,

2, Use a 5/16 inch nut driver to re

move four screws that retain the Ig

nition Stator to the Engine Adapter

Housing, Remove the Ignition Stator,

INSPECTION

1, Check Engine Adapter Housing for cracks, or other damage. Replace, if damaged,

2, Inspect Ignition Stator locating, dowel pin for damage, 3, Set VOM to ''+DC and to "Rxl" scale. Zero the meter. Connect one

meter probe to the Wire #20 connection at the wiring disconnect, and

the other test probe to the metal ring of the Ignition Stator, Meter

needle should swing upscale and read approximately 6 Ohms. If needle

does NOT swing upscale. Ignition Stator Trigger Coil is ’’open”. 4r Set VOM to ”+DC” and to ’’RxlOO” scale. Zero the meter. Connect one test probe to the Wire #8 connection at the wiring disconnect and the other probe to the Stator metal ring. Meter needle should swing upscale to approximately 225 Ohms. If needle does not swing upscale, the Sta tor Charge Coil is ’’open”.

6.6

Issued 3-78

ENGINE ADAPTER IGNITION STATOR

REASSEMBLY 7

1. Route the Ignition Stator wires

behind the Engine Adapter. Then mount the Engine Adapter, and reta

in with four 5/16t18 x 1 inch long

buttonhead screws. Tighten screws

to 11 foot-pounds.

FAN

1. Carefully align Fan hub keyway

with engine shaft keyway, then in

stall Fan onto engine shaft. Install the special square drive key into the aligned keyways, so that the in

stalled key is flush with, surfae.e of Fan hub. Key must not be permitted to ride inward against..curved radius of engine shaft keyway. Slide retain er washer and Belleville washer onto

5/16-24 X 1% inch long, capscrew (use

Grade 5 only). Apply LOC-.TITE.,601 to

capscrew threads. Install capscrew, torque to 19 Foot-Pounds.

2. Offset holes ensure correct in stallation of the Ignition Stator.

Align holes, then retain Ignition

Stator with four No. 10-32 screws,

3/8 inch long.

FLEX COUPLING

ROTOR

1. Install Flex Coupling onto Rotor

hub. Slide one washer over each 5/16-

18 X 3/4 inch long capscrew - RADIUS

OR CHAMFERED SIDE OF WASHER MUST BE

AGAINST THE FLEX COUPLING. Apply LOCTITE 601 to capscrew threads. Install

all three capscrews and torque to 19

Foot-Pounds.

Issued 3-78

2. Mount Rotor.to Fan bosses. Use two

flat washers under each ,5/16-18 x 3/4 inch long capscrew - RAD.IUS. 0R_ CHAMF

ERED SIDE OF WASHER, must: BE AGAINST

FLEK. C.OUELIN.G., Apply LOG-TITE 601 to capscrew threads. Install capscrews and torque to 19 Foot-Pounds.

STATOR

1. If previously removed, align

alternator adapter with stator can and install. Slide alternator ada pter and stator can carefully over

the rotor, with stator bolt holes in engine adapter and alternator adapter aligned. Seat the mating

flanges of engine and alternator

2. Slide a rubber vibration damp

ener into place over slide pan hole. Install bolt, with bolt head at bottom of slide pan. Install

metal spacer, rubber washer, metal

washer, lockwasher and hex nut. Re

peat for second vibration dampener. Tighten both hex nuts.

adapter against each other.

REAR BEARING CARRIER

1. Pull wire bundles through snap bushing in Rear Bearing Carrier. Then align Carrier with rotor bearing and with threaded holes in engine ada pter. Lightly tap Carrier over rotor bearing.. Install four stator bolts»

with lockwashers. Grounding lug goes under upper left hand bolt, fuel

pump ground wire under lower left bolt. Retain fuel shutoff solenoid clamp next to brush inspection window.

7.2

Issued 3-78

2, Make sure all four stator bolts are tightened down evenly. Engine adapter to alternator adapter mat ing flanges must be flush, as well as stator can to Rear Bearing Car rier mating flanges.

CONTROL PANEL

Refer to CONTROL PANEL:REMOVAL on

Pages 5.4 through 5.6. Retain the

Control Panel to stator can using

four capscrews and lockwashers.

Connect all wiring previously dis connected. Refer to a wiring diag ram for the specific unit for cor rect wiring connections. Use tie

wrap for neater wire bundles and

for wiring support where necessary. When installing brushes and brush holder, the red (No.. 4) wire goes next to the rotor bearing. Brush

ground wire extends from the other brush - retain the ground wire . with one of the brush holder reta

ining screws.

Issued 3-78

7,3

PART IV

ENGINE REPAIR

Section Title Page

8 COMPRESSION

Checking Compression....................................8.1

Remove/lnstall Cylinder Heads........................8.1

Remove Valves

Reface Valves and Seats.................................8.3

Check/Adjust Tappet Clearance.......................8.3

Install Valves....................................................8.3

Install Intake Valve and Stem Seal Install Exhaust Valve and Retainer Valve Guides

9 CRANKSHAFT & CAMGEAR

Crankshaft Removal

Checking the Crankshaft..................................9.1

Checking the Camgear.....................................9.2

Install Crankshaft and Camgear.......................9.2

Crankcase Cover..............................................9.2

Crankshaft End Play.........................................9.2

10 PISTONS, PINS & RODS

Remove Piston & Connecting Rod — 10.1

Remove Connecting Rod...............................10.1

Check Piston.................

Check Rings Check Connecting Rod Check Piston Pin Assemble Piston and Connecting Rod 10.3

■ Assemble Rings to Piston Install Piston and Connecting Rod ... 10.3

11 CYLINDERS

Inspection................................................... 11.1

Resizing

Honing............................................................11.1

Cylinder Finish and Cleaner

12 LUBRICATION

General Oil Recommendations

Oil Fill and Dipstick.........................................12.1

Crankcase Breathers

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

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

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

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

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

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

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

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

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

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

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..8.2

8.4

8.5

9.1

10.2

.'.10.3

11.1

11.2

12.1

Section Title Page

Checking Breathers ! Installing Breathers Oil Seal

Oil Make-up System........................................12.3

13 IGNITION

General ...........................................................13.1

Operation ........................................................13.1

Spark Plugs

14 STARTER MOTOR

General Check Starter Motordrive

Disassemble Starter Motor Drive ..... 14.1

Assemble Starter Motor Drive.........................14.2

Testing the Starter Motor Drive

Starter Motor Disassembly..............................14.2

Starter Motor Reassembly

15 CARBURETION

General Air Cleaner Servicing Carburetor Removal

Carburetor repair.............................................15.2

Float Valve Seat Replacement Checking Float Level Carburetor Reassembly

Integral Fuel Pump..........................................15.4

Carburetor Adjustment....................................15.4

16 GOVERNOR

General ...........................................................16.1

Governor Lever and Shaft Removal... 16.1 Governor Shaft Installation Governor Gear Installation Crankcase Cover Installation

Governor Shaft Adjustment.............................16.3

Adjusting Governed Idle..................................16.3

Top Governed Speed Adjustment — 16.3

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....

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■... —...................15.1

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15.1

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12.2

13.1

14.1

14.2

14.3

15.2

15.3

15.4

16.2

16.3

COMPRESSION

CHECKING COMPRESSION

Remove both spark plugs. Insert a compression gauge into one of the

spark plug openings. Crank the engine, using the electric starter.

Repeat test for second cylinder. Maximum pressure differential bet ween the two cylinders should not exceed 25 per cent. A greater pressure differential indicates loss of compression.

Loss of compression is generally caused by any of the following:

1. Defective/leaking cylinder head gasket

2. Sticking/improperly seated valves

3. Worn/broken piston rings or cylinder

REMOVE/INSTALL CYLINDER HEADS

^ ' nwim miKuui *~|p

Remove sheet metal cylinder head covers and air ducting around the engine cylinder heads. Note posi tions of cylinder head bolts, to ensure correct reassembly. Longer

bolts are used around the exhaust valve areas.

IMPORTANT

Wh.e.n removing and installing valves and valve parts, keep all parts

together as a set. Valves,.valve springs and tappets are not inter

changeable between valve ports.

To install cylinder heads,.first

install the correct head gasket.

DO NOT USE ANY KIND OF SEALANT ON

HEAD GASKET. Install cylinder head with bolts in their proper positi

on. Tighten all head bolts down evenly by hand. Then tighten bolts to 160 Inch-Pounds, in the proper

sequence.

Issued 3-78

8.1

REMOVE VALVES

Valve springs are retained by COLLARS and RETAINERS, as shown

above.

To remove exhaust valve, insert valve'Spring compressor upper jaw between the valve spring and the valve chamber. Insert lower spring

compressor jaw below the retainer.

Compress the spring, remove collars

from stem, release the spring, and finally remove the spring.

To remove Intake Valve, slip upper

jaw of valve spring compressor ov

er the top of the valve chamber.

Place the lower jaw of the spring compressor between spring and ret ainer, Compress the valve spring, then remove retainer.

Intake valves have a stem seal,

retained by the valve spring.

Lubricate the valve stem and pull

Intake Valve out slowly, to avoid

damage to the Valve stem seal.

8.2

Issued 3-78

REFACE VALVES AND SEATS

Valves and valve seats may be lap ped or ground, using a fine lapping

compound. Clean away all lapping compound after lapping. Exhaust valve faces have an angle of 45°, while Intake valves have an angle of 30°. Valve seat WIDTH should

be between 3/64 to 1/16 inch - if

seat is wider, use a narrowing stone or a cutter to decrease the seat width. Replace valve if its

margin is 1/64 inch (or less) aft

er refacing. Badly burned valves or valve seats should be replaced,

CHECK/ADJUST TAPPET CLEARANCE

Install valves in their correct po sition in cylinder, DO NOT INSTALL INTAKE VALVE STEM SEAL. Turn crank shaft until exhaust valve is at its

highest position. Then check Intake Valve stem to tappet clearance with a feeler gauge. Grind off end of In

take Valve stem to obtain proper clearance as shown in CHART below.

Turn crankshaft to bring Intake Valve

to its highest position, then check exhaust valve stem to tappet clear ance in the same manner. Grind end of

valve stem to obtain proper clearance.

VALVE TAPPET CLEARANCE

WITH SPRINGS

INSTALLED

SPRINGS NOT INSTALLED

INSTALL VALVES

Exhaust and Intake Valve compon ents are shown at right. A new

stem seal should be installed on

the Intake Valve, if required.

Heavier springs are used on the

Exhaust Valves. Apply a light film of oil on valve stems before installing valves in valve guides

INTAKE.. EXHAUST

INTAKE EXHAUST

Issued 3-78

.007”- .009” .009”- .011”

.005”- .007” .007”- .009”

INSTALL INTAKE VALVE AND STEM SEAL

Place seal and seal retainer wash

er in valve chamber. Lightly oil Intake Valve stem and guide, then install valve stem through guide. Insert end of valve stem through

the stem seal and seal retainer washer. As you slowly push the valve stem through the seal, rotate

the valve to prevent damage to seal.

Place the valve spring and retainer

into valve spring compressor. Comp ress spring until solid. (Make sure large diameter of spring retainer is away from valve chamber front.) Insert the compressed spring and retainer into valve chamber, then

open spring compressor about 3/8 to

1/2 inch. Push valve in and press seal and retainer further onto valve stem at same time. Drop the valve stem through the larger area of the retain er slot. Move compressor to center the **■ small area of valve retainer slot onto

the valve spring shoulder. Release the

spring tension and remove the compres sor.

)J SEAL

SLIDE STEM

THROUGH SEAL

' /

PUSH

SPRIHC

DOWN

OVER

VALVE STEkUl

COMPRESSOR I

INSTALL EXHAUST VALVE AND RETAINER

Install Valve spring and retainer into valve spring compressor and compress spring all the way. Then insert the compressed spring and

retainer into valve chamber. Push valve into place and slide stem through retainer. Hold the spring

toward the. cylinder head and posi tion valve so it is fully seated. Insert collars into valve, stem groove (grease may be used). Lower the spring until the retainer is around collars, then remove valve spring compressor. MAKE. SURE BOTH COLLAR HALVES ARE IN PLACE.

8.4

VALVE GUIDES

Valve Guides (Part No. 49271) are replaceable, providing the follow

ing tools are available:

1. Valve Guide Plug Gauge

2. Reamer

3. Reamer Guide Bushing

Sources for these tools will be

furnished on request.

If the flat end of the Valve Guide

Plug Gauge can be installed into

the Part No. 49271 valve guide

more than 5/16 inch, the guide is

worn and should be replaced. Use a Reamer and Reamer Guide Bushing to

ream out the worn Valve guide. Lu

bricate Reamer with kerosene. Ream

1/16 inch deeper than valve guide

bushing 49271 - DO NOT REAM THROUGH

THE GUIDE. Use a brass driver and press valve guide bushing 49271 in to place until top of bushing is

flush with top of valve guide. The

bushing requires no further reaming and a standard valve can be used.

Issued 3-78

. 8.5

CRANKSHAFT & CAMGEAR

CRANK SHAFT REMOVAL

Remove rust and burrs from power take-off end of crankshaft. Remove crankcase sump cover. If valves are installed, use valve spring compressor to compress Intake Valve

springs.

VALVE SPRING

-COMPRESSION

Note timing mark on Camgear and Crankshaft Gear. Carefully remove Camgear - tappets must be clear of cam lobes before camgear can be removed.

Remove spark plugs. Remove both connecting rod caps (see Section 10). Rotate crankshaft until connecting rods are free of crankshaft throws Remove crankshaft.

CHECKING THE CRANKSHAFT

The CHART below shows rejection

sizes of crankshaft wear points ■ replace crankshaft if any points

are worn smaller than the size

indicated.

PTC

JOURNAL JOURNAL

1.376

Issued 3-78

MAG

•1.376

CRANKPINS

1.622

CHECKING THE CAMGEAR

Inspect Camgear teeth for wear,

nicks or'damage. Camgear, Camgear

journals, and cam lobe rejection

sizes are listed in the CHART be low.

CAMGEAR

SHAFT

JOURNALS

0.623

INSTALL CRANKSHAFT AND CAMGEAR

CAM LOBES

1.124

Install crankshaft. Then install tappets. Finally, install Camgear.

Make sure timing marks are aligned

as shown at right. Install connec ting rods and caps as outlined in Section 10,

IGNITION

FLATS (2)

ON CAM

MAGNETO END

BEARING

PTO

BEARING

CAM LOBES

INSPECT

GEAR TEETH

CRANKCASE COVER

Protect oil seal when installing the crankcase cover. Use oil or grease

on sealing edge of the seal. Seal must slip easily over crankshaft. If

cover bolts with oil before installing. Tighten bolts down evenly to 10 Foot-Pounds.

CRANKSHAFT END PLAY

Crankshaft end play should be between 0.002 and 0,008 inch. To obtain correct end play, new gasket sets include 3 gasket thicknesses - 0.005,

0.009, 0.015 inch. Check end play with one 0.015 inch gasket installed. If end play is less than 0,002 inch, add additional gaskets in various

combinations to obtain correct end play.

9.2

Issued 3-78:

PISTONS,RINGS & RODS

REMOVE PISTON & CONNECTING ROD

Remove Cylinder Head (Section 8). Remove crankcase sump cover and cam-

gear (Section 9).. Remove Connecting Rod cap. Remove any carbon or ridge from cylinder wall. Push piston and rod out through top of cylinder.

IMPORTANT

Keep eaeh piston, connecting rod and cap together as a set. All parts must be installed in the same cylinder from which they

were removed. Parts are not interchangeable between sets.

NOTE

Connecting rod bolt locks are not used. Special hardened washers

are installed under connecting rod cap bolts.

REMOVE CONNECTING ROD

_____________________________

________

9 Use needle nose pliers to remove

piston pin lock. Then slide piston pin from piston and remove connec ting rod.

Using a ring expander, remove rings one at a time.

Issued 3-78

CHECK PISTON

If the piston is not to be replaced

or cylinder is not to be re-sized, piston should be checked. Clean car bon from top ring groove. Install a

NEW ring in the groove. If a 0.007

inch (or larger) feeler gauge can

be inserted in the space above the

ring, piston is worn and should be replaced.

CHECK RINGS

Clean all carbon from rings and from cylinder bore. Install old rings down

into the cylinder bore, one at a time, one inch into the bore. Check ring gap with feeler gauge. If gap’is greater

than shown in CHART below, replace the ring.

NEW PISTON RING

COMPRESSION

RING

OIL RING,

6.035 . 1 0.045

CHECK CONNECTING ROD

Replace rod if crankpin bearing is scored or worn. DO NOT ATTEMPT TO

FILE OR FIT THE ROD. The following CHART shows rejection sizes of crank-

pin bearing and piston bearing holes.

CRANKPIN

BEARING

PISTON PIN

BEARING

1.252. 0.802

CHECK PISTON PIN

Replace the piston pin if it is more than 0,0005 inch out-of-round.

10.2

Issued 3-78

ASSEMBLE PISTON AND CONNECTING ROD

Place a piston pin lock into the

groove at one side of piston. In sert piston pin from opposite side of piston, through rod, unt il it is stopped by the pin lock. Install second piston pin lock.

Make sure locks are firmly set

into grooves. Oil holes in conn

ecting rods must face as shown at right.

ASSEMBLE RINGS TO PISTON

Correct piston ring positioning is

shown at right. An expander goes

under the oil ring. The dot on the

second compression ring must face

direction shown.

INSTALL PISTON AND

CONNECTING ROD

Oil the rings and the piston skirt. Use ring compressor to compress the

rings as shown at right.

Turn the piston and ring compressor upside down on a clean, flat bench. Push piston downward until compres

sor is flush with piston head. Draw compressor tight, then loosen slig

htly. Notch on piston must face the

fly^eel side of cylinder when in stalled, as shown at right.

PROJECTIONS

OIL HOLE IN

CONNECTING ROD

Rotate crankshaft so that the journal is all the way down. Clean and

oil cylinder bore. Carefully push the piston into cylinder bore, Wlien all rings are captured by the cylinder bore, remove ring compressor.

Issued 3-78

10,3

Oil the crankshaft crankpin. Pull

connecting rod against crankpin and install end caps so that their ass embly marks are aligned. Install oil dipper. Install special hardened washers under bolt heads. Install bolts and tighten to 190 Inch-Pounds. Rod must be able to move sideways on

the crankpin after torquing.

19070 PISTOH RIMC

COMPRESSOR

10.4

Issued 3-78

INSPECTION

Inspect cylinders for cracks, bro

ken fins, stripped bolt holes, and

scoring of cylinder walls. Use an inside micrometer or telescoping gauge to determine size of cylind er bore. Measure at-right angles as shown at right. If bore is more than 0,003" oversize, or more than

0.0025" out-of-round, it must be

resized. The following CHART lists STANDARD cylinder bore diameters.

CYLINDERS

STANDARD CYLINDER

BORE DIAMETERS

RESIZING

MAX, MIN.

3.4375

3.4365

ALWAYS RESIZE TO EXACTLY O.OlO", 0.020", or 0.030" OVER STANDARD SIZE, AS SHOWN IN THE PRECEDING CHART, If resizing is done accurately, stan

dard oversize pistons and rings will fit perfectly and proper clearan ces will be maintained. Cylinders can be resized with a hone. Use the stones and lubricants recommended by the hone manufacturer to produce the correct cylinder wall finish, (NOTE;- An acceptable honing oil can

be made by mixing 4 parts SAE 30 oil with 1 part kerosene.) If a bor

ing bar is used, a hone must be used after the boring operation to pro

duce the proper cylinder wall finish.

CAUTION

If cylinders are to be resized at a "Job Shop", do not take pistons

with the cylinders. If pistons and cylinders are sized to match,

seizure will occur. Oversizing must be doné to exact oversizes spec

ified in CHART.

HONING

Honing can be done with a portable electric drill. However, it is easier

to hone with a drill press. Before starting the honing operation, clean cylinder walls thoroughly.

Issued 4-78

11.1

Fasten cylinder to honing plate. Use a level to align drill press

spindle with bore. Oil surface of drill press table liberally. Set plate and cylinder on drill press table. DO NOT ANCHOR TO TABLE. If

using portable drill, set plate

and cylinder on floor. Install hone drive shaft into chuck of drill press or portable drill. In

sert hone into cylinder. Connect

drive shaft to hone and.set stop on drill press so that hone can extend only 3/4 inch to 1 inch

from top or bottom of cylinder.

If using a portable drill, set a wood block inside cylinder as a

stop for the hone.

With hone in center of cylinder bore, tighten adjusting knob until

stone fits snugly against cylinder wall. DO.NOT FORCE. Hone should

run at 300 to 700 rpm. Lubricate hone as previously recommended.Be

sure that cylinder and hone are centered and aligned with drive shaft and drill spindle. Start the drill. As the hone spins, move

it up and down at lower end of cylinder, (Cylinder is probably not worn at bottom, but will guide the hone to straighten the bore.)

As bottom of cylinder enlarges, gradually increase stroke lengths until hone travels full length of cylinder bore. DO NOT EXTEND HONE MORE THAN 3/4 to 1 INCH AT EITHER END OF CYLINDER BORE. As cutting

tension decreases, stop hone and tighten adjusting knob. Check the

cylinder bore diameter frequently with an accurate micrometer. Hone

about 0.0005 inch larger than required to allow for shrinkage when

cylinder cools. When within 0.0015 inch of desired size, change

from rough stone to finishing stone.

CYLINDER FINISH AND CLEANER

The finished cylinder wall should

have a crosshatch appearance, as

illustrated at right. This will

permit proper lubrication and ring break-in.

After honing, clean entire cylinder thoroughly with a brush, soap

and hot water. Do NOT use kerosene or gasoline - solvents of this

type will not remove all of the honing grit.

11.2

Issued 4-78

GENERAL

Change oil after the first 5 op

erating hours, every 25 hours of operation thereafter. Remove oil drain plug and drain oil while

engine is warm. Reinstall drain

plug. Remove dipstick and fill

engine crankcase with new oil of proper grade. Use same grade of oil in OIL MAKE-UP TANK as was

used in crankcase. Crankcase oil capacity is approximately 3,5 pints (1,65 liters).

LUBRICATION 12

OIL RECOMMENDATIONS

Use any high quality detergent oil

having a classification that in cludes SC, SD or SE, as recommend ed in CHART at right. No special additives should be used.

OIL FILL AND DIPSTICK

A plastic oil fill tube is used,

with the bottom of the tube press

ed into a rubber grommet and seal ed, A leak at the base of the. tube

or in the dipstick seal can cause

loss of crankcase Vacuum, This, in turn, will result in smoke discha rge from the exhaust and failure of the oil make-up system to func tion,

CRANKCASE BREATHERS

RECOMMENDED SAE VISCOSITY GRADES

mmmmi

' 10W-30, 10W-40

op-20

’C-30

TEMPERATURE RANGE ANTICIPATED BEFORE NEXT QILCHANGE

-20

20 30

100

—S-

*If not available, a synthetic oil may be used having

5W-20, 5W-30 or 5W-40 viscosity.

The crankcase breathers act to maintain a partial vacuum in the crank

case, This vacuum, prevents oil from being forced out at the rings, oil seals, and gaskets.

Issued 4-78

12.1

CHECKING BREATHERS

To remove breather assemblies, re move carburetor air cleaner and

intake manifold. Remove the dipst ick tube. Then remove air guide. Finally, remove breathers.

If a 0,045" wire gauge can be in

serted between the breather fiber disc valve and body, fiber disc valve is defective. A spark plug wire gauge may be used. DO NOT USE FORCE WHEN CHECKING THIS CLEARANCE.

INSTALLING BREATHERS

Install a new gasket each time the

breather assemblies are removed

and reinstalled. Make sure breath er gaskets are properly located.

Locate gasket notches as shown at

right. Make sure retaining screws

are tight to prevent leakage.

Make sure breather tubes are not

hardened or damaged, and that the

tubes seal properly.

OIL SEAL

Always install the oil seal with

sharp edge of rubber toward engine interior. Lubricate oil seal in side diameters with Lubriplate (or equivalent), before assembling en gines, Press replacement seals in, flush with engine.

12.2

Sri

The oil dipper must be properly

installed on the number 1 connect ing rod, as shown at right. A special washer is installed be

tween dipper and bolt head.

OIL MAKE-UP SYSTEM

The Oil Make-up System functions to prevent dangerously low engine crankcase oil levels during operation. The system consists of (1) an Oil Make-up TANK with low oil level shutdown switch, (2) an Oil Make up PUMP, (3) an Oil Make-up PROBE, and (4) interconnecting lines.

The Oil Make-up' Pump will not act while the tip of the Oil Make-up Probe is submerged in oil. If oil

level in the crankcase should drop

to about the 48 ounce level, the

tip of the Probe will be exposed to

crankcase vacuum/pressure pulses. These pulses actuate the Oil Make up Pump diaphragm and the pump ac

tion then draws oil from the Tank. ■ When the Probe tip is again submerg

ed in oil, pumping action stops.

If Oil Make-up Tank oil level should drop below the OIL CHANGE

LEVEL arrows on the tank side, the float-operated Low Oil Level Shutdown Switch will ground the engine ignition system and the

engine will automatically shut down.

During initial filling of the engihe crankcase, approximately 56 ounces

(3^ pints) of oil is added. This a-

mount of oil brings the oil level up

to the oil dipstick FULL mark. The Oil Make-up System will not start to pump oil into the crankcase until oil level has reached the 48 ounce point, about halfway between the dip

stick FULL mark and ADD 1 PINT mark.

Issued 4-78

IGNITION

GENERAL

The engine Ignition System is a solid state capacitor discharge type,

often called a "breakerless” system due to the absence of breaker

points. The system consists of the following components:

1, Engine flywheel magnet 2, Ignition stator

3, Ignition Module

4, Ignition Coil

5, Spark Plugs

5. Interconnecting wiring

OPERATION

Engine rotati.on causes the starter ring gear to turn. A magnet rotates with the ring gear to induce curr

ent flow into the charge and trigg

er coils of the Ignition Stator. Current flow from the Charge coil passes through Wire #8 and charges a capacitor in the Ignition Module, At 26° BTDC of the engine piston

stroke, current flow from the Igni

tion Stator trigger coil is deliver

ed through Wire rr20 to the base of a

transistor in the Ignition Module,

causing the Ignition Module capacitor

to discharge. The capacitor discharg

es through Wire #12, through the Ig nition coil primary windings, and

through Wire #10 to ground. Current

flow through the coil primary wind

ings induces a high voltage into the

ignition coil secondary windings to

fire the spark plug gaps.

Ignition Stator

Magnet

Low Oil

Level Shutdown

Switch -im

Starter Ring Gear

Ignition Module

Ignition

Coil

Spark Plugs I

SPARK PLUGS

Use a Champion J-8, Auto-Lite A-71, or AC, No, GC-46 spark plug. Set plug gap to 0,030 inch. Clean spark plugs with pen knife or with wire

brush and solvent, LO NOT GRIT BLAST, Replace plug if electrodes are burned away or if porcelain is cracked.

Issued 4-78 13.1

GENERAL

STARTER MOTOR

PLASTIC

CAP

’pin'' SPpViSa SPBINO

An exploded view of the starter is shown above. The starter uses a

gear type engagement, similar to an automobile. Energizing the starter

motor causes the helix on the starter to drive a pinion gear into eng

agement with a ring gear. The pinion gear then cranks the engine.

CHECK STARTER MOTOR DRIVE

When the starter motor is energized, the pinion gear should move out

on its helix to engage the ring gear. If the motor drive does not re act properly, inspect helix-and pinion gear for freedom of movement. If sticking or binding occur, the condition must be corrected. Pinion

must move freely on its helix. DO NOT LUBRICATE DRIVE ASSEMBLY.

PINION

iNo Cap

DISASSEMBLE STARTER MOTOR DRIVE

Clamp starter drive cap in a vise. DO NOT CLAMP MOTOR SHELL IN VISE. Use two screwdrivers to remove the

plastic cap, as shown. If cap be comes damaged, it must be replaced,

Use a 1/8 inch diameter punch and

a hammer to drive the roll pin out.

Rest retainer in a wood V-block, as

shown.

Issued 5-78

14.1

ASSEMBLE STARTER MOTOR DRIVE

Install pinion gear with beveled edge away froin starter. Install clutch and gear onto shaft, follow ed by cup, spring and retainer.

Press or drive roll pin through the

slot on retainer and through hole in armature shaft. Position slot of roll pin up as shown. Roll pin must

be centered within 1/32 inch. Press

plastic cap into position until it locks into place,

TESTING THE STARTER MOTOR

To check the starter motor, the following equipment is needed:

1. Tachometer capable of reading 10,000 rpm 2, A 12 volt battery 3* Ammeter capable of reading 50 Amperes

Connect starter motor, battery and

ammeter as shown at right. Insert tachometer into starter motor and energize motor. Motor should run at 6200.rpm (minimum) and current draw should not exceed 16 amperes (maximum), DISREGARD SURGE CURRENT,

STARTER MOTOR DISASSEMBLY

To disa-ssemble the starter motor, first remove the starter drive as outlined previously. Then remove the mounting bracket from the

starter motor shell by removing the two through bolts.

Push down on armature shaft and

slide the shell up and off. Remove

armature from end cap.

14.2

CAUTION

Never clamp starter motor in a vise or strike motor with a hammer. Motors contain two ceramic magnets. These magnets

can be broken or cracked if housing is deformed or dented.

Inspect starter motor parts. Clean all dirt from armature, end cap,

motor support, etc. DO NOT SOAK BEARINGS, HOUSING OR ARMATURE IN A

CLEANING SOLUTION. Clean commutator with fine sandpaper - NOT WITH

EMERY CLOTH. Check brushes for poor seating, weak springs, dirt,

oil or corrossion. Brush spring tension should measure 17 - 25 oun

ces. When worn to 1/8 inch or less, replace brushes. See illustrat ions below.

STARTER MOTOR REASSEMBLY

Make sure all. parts have been thoroughly inspected. Lightly lubri

cate end cap bearing with No. 20 oil, then reassemble as follows:

1. Insert brushes into their resp

ective holders. A locally fabrica ted tool, as shown at right, should

be used to hold brushes clear of

2. Install armature into end cap.

Issued 5-78

3. Slide motor shell over armat

ure with notch toward end cap. Line up marks on end cap and shell. Slide

drive cap oyer end of armature and install through-bolts and lock wash ers, Tighten through-bolts to 45-55 inch-pounds. Make sure armature turns freely, then install starter drive components as outlined previ ously.

14.3

GENERAL

CARBURETION

The engine uses a 2-piece, dovjn-

draft carburetor, with separate high speed and idle speed fuel circuits. The carburetor includes an integral pulse-type fuel pump, capable of priming at an 18 inch

maximum lift. Carburetor .adjust ment procedures differ from those

of single cylinder engines. Adj

ustment procedures outlined in

this manual must be carefully fol

lowed,

AIR CLEANER SERVICING

Worn or damaged air cleaner gaskets must be replaced. Bent mounting

studs must be straightened or replaced.

Clean and re-oil Foam Pre-cleaner

every 25 operating hours or every

3 months, whichever comes first,

1, Remove wing nut and cover.

2, Slide Foam Pre-Cleaner off

paper cartridge,

3, A-Wash Foam Pre-Cleaner in liq

uid detergent and water.

B-Squeeze dry

C-Oil with 1 ounce engine oil.

Squeeze to distribute oil,

4, Assemble Pre-Cleaner to paper

cartridge. Install cover and tighten wing nut down.

Each 100 hours of operation or every year, whichever occurs first, remove paper cartridge. Clean by tapping gently on a. flat, surface. Replace if damaged or extremely dirty.

FOAM

PRE*OLEANER

IMPORTANT

The paper cartridge used on the TXP alternator engines, is a special FLAME RETARDANT element. DO NOT SUBSTITUTE ANY OTHER ELEMENT. ONLY

A FLAME RETARDANT ELEMENT MAY BE USED.

Issued 5-78

15,1

CARBURETOR REMOVAL

The carburetor and intake manifold are removed as an assembly. Discon nect fuel line from integral fuel pump. DO NOT BREAK PLASTIC NIPPLE ON

FUEL PUMP. Remove screws that retain intake manifold to engine.

Idle Speed

Governed Idle Tang

Stop Tang

Adjustment Screw

Disconnect governor link from

governor lever.

Disconnect vacuum line from its

fitting at fuel pump. Remove

carburetor and intake manifold,

CARBURETOR DISASSEMBLY

Remove idle and needle, valves. Replace if damaged. Remove fuel pump body. Remove upper carbur

etor body, float and float valve.

Check float for leakage, replace

if damaged. Check float valve and seat, replace if damaged or worn. DO NOT CLEAN CARBURETOR IN ANY SOLVEl^T UNLESS ALL RUBBER SEALS

AND NYLON PARTS HAVE BEEN REMOVED,

CARBURETOR REPAIR

When reassembling carburetor, use new parts where necessary. Always

use NEW GASKETS, Carburetor repair

kits are available. The float valve has a Viton tip. Float valve seat

is pressed into the carburetor body,

N .1*

15.2

Issued 5-78

FLOAT VALVE SEAT REPLACEMENT

Press new seat flush with body, us

ing old seat and screw as a driver.

DO NOT PRESS SEAT BELOW SURFACE OF

BODY.

Clamp the head of a self-threading screw in a vise. Then turn carburet or body to thread screw into seat.

Continue turning carburetor to draw

the seat out. Install a new seat in

to carburetor body. New seat has a starting lead.

Install float valve,

CHECKING FLOAT LEVEL

With body gasket, float valve and

float installed on upper body, the float should be parallel to the

body mounting surface.

Issued 5-78

If not parallel, bend tang on float

until just parallel. DO NOT PRESS

ON FLOAT TO ADJUST.

15.3

If choke shaft and plate were remov

Make sure holes in body gasket are

properly aligned with body as shown

ed, choke plate must be reinstalled

as shown above. Tighten two choke

above. Fasten upper and lower bodies plate screw - DO NOT OVERTIGHTEN, together with mounting screws.

Screw in needle and idle valves until they just seat. Then back off on

both valves 1% turns. These settings are approximately correct. Final

adjustment will be made with engine running.

INTEGRAL FUEL PUMP

The integral fuel pump is operated by crankcase vacuum/pressure pulses, See exploded view at right.

Remove three screws that attach pump to carburetor. Lift pump body off carefully to prevent damage to diaphragm. Inspect diaphragm for punctures, wrinkles and wear. Replace, if damaged. Make sure diaphragm mounting surf aces are free of, nicks, burrs, debris. Inspect pulse chamber spring and flapper valve springs for distortion or deterioration. Replace, if necess ary. Inspect outer pulse chamber diaphragm and cover plate gasket for cracks and punctures, When assembling fuel pump, tighten screws in a stag gered sequence to avoid distortion of diaphragm,

CARBURETOR ADJUSTMENT

Carburetor adjustment procedures are outlined on Page 4.14, Test 23,

15.4 Issued 5-78

GOVERNOR

general

|The governor functions to maintain

engine speed at 1800 rpm, even though the load may vary. The governor spring tends,to move the throttle open. Counterweight force tends to close the throttle. Engine speed at which spring and counterweight forces balance is

called the governed speed. Governed speed can be changed by varying spring tension.

GOVERNOR LEVER &SHAFT REMOVAL

Drain crankcase oil. Rotate crankshaft

until intake valve on No. 1 cylinder

is wide open to relieve side pressure

on cam shaft bearing. Remove crankcase cover.

Governed Idle Tang

Governor

Lever Nut

Governor

Shaft

Governor

Lever

Idle Speed

Adjustment Screw

Governor Speed

Adjusting Nut

Governor

Spring

Governor Link

High Speed

Slop Tang

Inspect governor for wear on gear teeth,

pivot pins, and counterweights. Inspect

governor cup. Replace governor, is nec

essary.

Note location of thrust washer when

removing governor from crankcase cover

CUP

COUNTER

WEIGHTS

Issued 5-78

16.1

Loosen nut and remove governor lever. Rotate crankshaft to place crankshaft

gear timing mark at about the 10 o’clock position. Remove E-ring and thick washer at outer end of governor shaft. Governor shaft will slide down into gear case. Rotate crankshaft

back and forth slightly until shaft

can easily be removed,

GOVERNOR SHAFT INSTALLATION

Install thin thrust washer onto

governor shaft before installing

shaft into crankcase. Slide the shaft up into position, rotating

crankshaft to obtain clearance.

Install thick washer, then retain shaft with E-ring, Install gover

nor lever onto shaft and tighten

nut lightly. Rotate shaft until

. crank touches rib, as shown at

right. IF GOVERNOR SHAFT IS NOT IN PROPER POSITION BEFORE ASSEMB LING CRANKCASE COVER, CORRECT

GOVERNOR ADJUSTMENT WILL NOT BE OBTAINED,

GOVERNOR GEAR INSTALLATION

Install governor gear and thrust washer onto shaft in crankcase cover as shown at right. Make sure the gear rotates freely. Be sure weights and cup move freely

with no evidence of binding.

16.2

Issued 5-78

CRANKCASE COVER INSTALLATION

Position engine with crankshaft

in a vertical position. Rotate

crankshaft to place timing mark on can gear at 12 o’clock. In

stall gasket and install cover,

MAKE SURE GOVERNOR GEAR TEETH ARE IN MESH - use long thin screw

driver to rotate governor gear, if

necessary.

governor shaft adjustment

Adjust governor lever as outlined in Test 32, Page, 4,18.

ADJUSTING GOVERNED IDLE

Adjust governed idle as outlined in Test 23, Page 4,14,

TOPGOVERNED SPEED ADJUSTMENT

Adjust governor as outlined in Test 32, Page 4,18.

Issued 5-78

16,3

Generac Power Systems TXP User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

GENERAC

PART II

TROUBLE DIAGNOSIS

DIAGNOSTIG FLOW CHARTS 3

IMTRODUCTION

ENGINE WON’T CRANK

Battery Charge Tests

PART III

ALTERNATOR REPAIR

ALTERNATOR

CRANKSHAFT & CAMGEAR

PISTONS,RINGS & RODS

IGNITION

STARTER MOTOR

CHECK STARTER MOTOR DRIVE

DISASSEMBLE STARTER MOTOR DRIVE

ASSEMBLE STARTER MOTOR DRIVE

TESTING THE STARTER MOTOR

STARTER MOTOR DISASSEMBLY

STARTER MOTOR REASSEMBLY

CARBURETION

AIR CLEANER SERVICING

CARBURETOR REMOVAL

CARBURETOR DISASSEMBLY

INTEGRAL FUEL PUMP

CARBURETOR ADJUSTMENT

GOVERNOR LEVER &SHAFT REMOVAL

GOVERNOR SHAFT INSTALLATION

GOVERNOR GEAR INSTALLATION

CRANKCASE COVER INSTALLATION

ADJUSTING GOVERNED IDLE

TOPGOVERNED SPEED ADJUSTMENT