Timing Gear Assembly

cylinder head, m a k i n g c e r t a i n t h a t t h e s h a f t

installed, chill the inserts in dry ice. Start the inserts

supports are positioned with the longer section

into the counterbore (valve seat side up). Using a

down. Refer to figure 3-9.

valve seat installation tool, drive the insert down

tightly into the counterbore. Stake the valve seats in

position using a center punch. Stake at two or three

points around the edge of the seat. Refinish the

valve seat inserts.

(4) Install the valves (30 and 31) in their

original positions. Install the springs (29), retainers

(28) and locks (27). Using a spring compressor,

compress the springs and install the caps (26).

(5) Assemble remaining components in the

reverse order of disassembly.

e. Installation.

(1) Clean the top of the cylinder block.

Caution: Inspect top of the pistons for

foreign objects before installing the head.

(2) Install guide studs in holes 11 and 12.

Refer to figure 3-8.

Figure 3-9. Rocker arm shaft support installation.

Caution: The rocker arms are not

designed to contact the valve stems at the

center, but 1/16 inch off center. Do not bend

the rocker arms to make them line up center to

center with the valve stems.

(11) With the valve lash adjusting screws (13,

fig. 3-7) correctly seated in the push rods (23),

tighten the shaft support stud nuts and capscrews

to a torque of 18 to 22 ft Ibs.

Figure 3-8. Guide stud location and torquing sequence.

(12) Install the oil tube between the rocker

arm shaft and cylinder head.

(3) Be sure the new cylinder head gasket is

(13) Connect the rocker arm oil feed line from

installed with the proper side up. The gasket is

the head.

marked to indicate which side is to be installed on

(14) Install the thermostat housing. Connect

the cylinder block. Do not use any sealer or gasket

the coolant outlet tube from the thermostat housing

dope on any part of the cylinder head gasket

to the radiator. Install the coolant bypass tube and

assembly. A thin coat of light grease may be used

connect the lead at the coolant temperature sending

on the top deck of the cylinder block around the

unit.

cylinder bores.

(15) Install the manifold. Refer to TM 10-

(4) Position the fire rings inside the cylinder

3930-624-12.

bores of the gasket and ensure that the gasket does

(16) Close the drain cocks and refill the

not overlap the fire rings.

cooling system with the proper coolant.

(5) Lower the cylinder head to the block with

(17) Adjust the valve clearance. Refer to TM

the aid of a sling. The head should be properly

10-3930-624-12.

located by the guide studs.

(18) Install a new rocker arm cover gasket.

(6) Install the capscrews in all locations

Install the rocker arm cover and vent hose.

except those occupied by guide studs.

(19) Install the seat and seat deck, air cleaner,

(7) Remove the guide studs and install the

and side panels.

remaining capscrews. Tighten the capscrews in the

3-13. Timing Gear Assembly

specified numerical sequence (fig.3-8) to 55 ft Ibs.

(8) Retighten the capscrews, in numerical

a. Removal.

(1) Remove the radiator and fan belt. Refer to

sequence, to a final torque of 110 ft Ibs.

TM 10-3930-624-12.

(9) Install the push rods and make sure they

(2) Remove t h e h y d r a u l i c p u m p a n d

seat properly in the lifters.

crankshaft pulley.

(10) install the rocker arm assembly on the

3-12