CHAPTER 9 REPAIR OF ENGINE

TM 10-3930-632-34

CHAPTER 9

REPAIR OF ENGINE

Section I. DESCRIPTION

electrical system, including a coil and distributor type

9-1.

General

ignition system, starting system, and battery charging

system with an alternator. Detailed descriptions of the

The engine is a four-cylinder, four stroke-cycle,

various components of the engine are presented in

water-cooled, valve in block, pressure-lubricated,

applicable paragraphs through this chapter.

gasoline engine. The engine is equipped with a 12-volt

Section II. ENGINE WEAR LIMITS

parts. Refer to this table to determine if parts can be

9-2.

General

reinstalled or if replacement of parts is necessary.

Table 9-1 lists allowable wear limits of engine

Table 9-1. Engine Wear Limits

Engine Part

Point of Measurement

Wear

Limit

Valve Guides ..................................

Length ............................................................

2-9/32

(intake and exhaust) .......................

Outside Dia. ...................................................

5645/5635

Stem Hole Dia................................................

3167/.3157

Wear Limits-Max. Dia ....................................

3182

Distance, Cyl. Block Contact

Face to Guide ................................................

7/8

Intake Valves ..................................

Stem Dia. .......................................................

3149/.3141

Wear Limits-Min. Dia .....................................

.3121

Seat Angle ....................................................

Stem Clearance Limits...................................

001/.0006

Wear Limits-Max. Cl . ....................................

.003

Desired Stem Clear .......................................

.0008

Exhaust Valves ...............................

Stem Dia. .......................................................

3132/.3124

Wear Limits-Min. Dia. ....................................

.3104

Seat Angle .....................................................

Stem Clearance-Limits ..................................

.0047/.0043

Wear Limits-Max. Cl. .....................................

.0063

Desired Stem Cl.............................................

.0035

Valve Springs..................................

Outside Dia. ...................................................

31/32

Length-Valve Closed......................................

1-45/64

Load-Valve Closed.........................................

47-53#

Wear Limits-Min. Wgt. ...................................

42#

Length-Valve Open .......................................

1-27/64

Load-Valve Open ...........................................

96-104#

Wear Limits-Min. Wgt. ...................................

86#

Camshaft .......................................

Brg. Journal Dia. #1 .......................................

1.8095/1.8085

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

#2 ...........................................

1.7465/1.7457

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

#3 ...........................................

1.2475/1.2465

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

Bushing-Inside Dia. #1...................................

1.8125/1.8115

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

#2 ...........................................

1.7502/1.7495

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

#3 ...........................................

1.2505/1.2495

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

Bushing-Clearance Limits ..............................

004/.002

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

End Play

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

007/.003

9-1