TM 5-4320-218-15
b. Remove the Allen-head setscrew from the
107. Cleaning and Inspection of
left-hand side of the crankcase. Improvise a
Timing-Gear Train
gear puller by using 3/8-inch flat washers, a
a. Wash the removed gears with an approv-
3/8-16NC x 4-inch bolt, and a socket of suffi-
ed cleaning solvent; dry thoroughly. Discard
cient diameter to clear the shoulder of the idler
the gear-cover gasket.
gear shaft (29). Insert the bolt through the
b. Clean the gear-cover spacer with a cloth
washers and socket; position the socket over
dampened with an approved cleaning solvent;
the shoulder of the idler gear shaft so that the
dry thoroughly.
socket rests on the idler gear (29). Screw the
c. Examine the gears for broken, cracked,
bolt into the shaft and, using a wrench, take
or chipped teeth. Replace any damaged or
up on the bolt to remove the shaft; remove the
excessively worn gears.
shaft and idler gear.
d. Inspect the idler gear shaft for scoring or
c. Remove the three cap screws (7, fig. 32)
pitting. Remove any roughness with a fine
and lockwashers (6) that secure the camshaft
grade of emery cloth.
gear (5) to the camshaft. Pry the gear from
e. Examine the camshaft thrust-plunger
the camshaft. Pull the camshaft thrust plung-
spring for pits or breaks. Replace a defective
er (8) from the end of camshaft. Remove the
spring.
plunger spring (9).
12
Tappet screw
7
Cap screw
1
Intake and exhaust valve
8
Camshaft thrust plunger 13
Rotator cap
2
Valve seat insert
14
Spring seat lock
9
Spring
3
Valve stem guide
15
Spring seat
10
Tappet
4
Camshaft
16
Inlet and exhaust spring
11
Locknut
5
Camshaft gear
6
Everlock type lockwasher
Figure 32. Camshaft and valve, exploded view.