Flywheel - TM-10-3930-242-340092

TM 10-3930-242-34

The proper angle for the seating face of both the

lies, rocker arms, and rocker arm shaft (para

valve and valve insert is 30 degrees. The angle

3-14).

o f the valve seat insert must be exactly the

(5) Install cylinder head and injectors (para

3-19).

s a m e as the angle of the valve face so as to

( 6 ) Prior to starting the engine, a complete

p r o v i d e proper seating of the valve. When new

tuneup should be performed (paras 3-7, 3-13,

valve inserts are installed or old inserts refaced,

3-14, and 3-15.

t h e work must be done with a grinding wheel,

( 7 ) Start the engine and check for leaks in

Grind the inserts as follows:

t h e fuel, water and lubrication system.

( 1 ) First apply a 30 degree grinding wheel

(8) Install

rocker

cover

o n valve seat insert.

arm

(TM

10-3930-242-12).

(2) Use a 60 degree grinding wheel to open

t h e throat of the insert.

3 - 2 1 . Flywheel

(3) Then grind top surface with a 15 degree

a. General. The flywheel assembly is bolted

wheel to narrow width of the seat from 3/64- to

securely to rear end of crankshaft with six bolts

5/64-inch. The 30 degree face of the insert may be

in any one of six positions. A heat-treated steel

adjusted relative to the center of the valve face

s p u r gear, having chamfered teeth, is shrunkfit

with the 15 degree and 60 degree grinding

on the rim of flywheel.

wheels.

b. Removal.

(4) After the valve inserts have been

(1) Remove engine (para 2-5).

g r o u n d , the cylinder head should be thoroughly

c l e a n e d . Then check the concentricity of the

CAUTION

v a l v e seats relative to the valve guides. Total

When removing or installing attaching

runout for a good valve seat should not exceed

bolts, hold flywheel firmly against

0 . 0 0 2 inch. If total runout exceeds 0.002 inch,

crankshaft by hand to prevent it from

check for bent valve guide before regrinding in-

slipping off end of crankshaft. The fly-

sert.

wheel is not dowelled to crankshaft.

(5) After valve seats have been ground, the

(2) Remove flywheel attaching bolts and

p o s i t i o n of the contact area between the valve

scuff plate while holding flywheel in position by

and valve insert should be determined in the

hand, then reinstall one bolt (fig. 3-45).

f o l l o w i n g manner:

( 3 ) Attach flywheel lifting tool to flywheel

(a) Apply a light coat of valve grinding

with two 3/8 inch -16 bolts of suitable length.

c o m p o u n d paste to the valve seat insert.

(4) Attach chain hoist to lifting tool.

(b) Lower stem of valve in the valve guide

( 5 ) Remove the remaining flywheel attach-

and "bounce" valve on seat. DO NOT ROTATE

ing bolt.

VALVE. This procedure will show (on the valve

(6) Move upper end of tool back and forth to

f a c e ) the area of contact. The most desirable

l o o s e n flywheel, then withdraw flywheel from

area of contact is at the center of the valve face.

c r a n k s h a f t and flywheel housing.

m. Install Exhaust Valves. With the cylinder

c. Cleaning and Inspection.

head thoroughly cleaned, the valve guides

(1) Cleaning. Clean the flywheel and attach-

c h e c k e d or replaced, the valves and valve seat

i n g parts using solvent P-D-680, or equal. Dry

i n s e r t s ground, install the valves as follows:

thoroughly.

( 1 ) Apply a light coat of engine oil on the

v a l v e stems and install the valves in the cylin-

( 2 ) I n s p e c t i o n . After removal, check fly-

der head.

wheel for cracks, scoring, or overheating of the

( 2 ) Secure valves in place temporarily with

clutch contact face. If flywheel clutch surface is

masking tape. Then turn head over, resting

s c o r e d , it may be refaced. However, not more

valve heads on wood block or board and install

than 0.020 inch of metal should be removed from

spring seats, valve springs, valve spring caps

flywheel and all radii should be maintained. Al-

and locks (fig. 3-44).

though flywheels seldom wear to the point

w h e r e replacement is required, flywheel ring

NOTE

gears may become worn due to normal usage or

The distance from the top of the cylinder head to

the bottom of the valve spring seat counterbore is

d a m a g e d by improper use of the starting motor

11/64inches.

t o the extent where they must be replaced. The

t e e t h on the ring gear should be examined. If

(3) Check the position of the exhaust valves.

replacement of the ring gear is necessary, follow

( 4 ) Install cam followers, push rod assemb-

t h e procedure outlined below.

3-52