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 TM 55-1905-217-34
(b) With a suitable drift, drive the pin from the roller. Exercise caution in removing the cam follower body and roller
from the fixture as the follower pin is seated on top of a spring loaded plunger in the fixture body. Prior to installing a new
roller and pin, remove any burrs on the surfaces of the cam follower at the pin holes.
(c) Position the follower body in the groove of the fixture with the proper size plunger ex- tending through the roller
pin hole in one of the legs of the follower body. Coat the roller bushing and roller pin with engine oil.
(d) Install the roller in position in the cam roller body. The plunger, when released, will extend into the roller
bushing and assure accurate alignment of the bushing with the roller pin holes in the follower body.
(e) Start the roller pin squarely into the follower. Then, carefully drive the pin into the assembly until the pin is
centered in the legs of the follower (fig. 3-54).
(f) Check the side clearance between the roller and the follower body. This clearance must be .015 inch to .023
inch.
NOTE
Immerse a new or solvent-cleaned cam follower assembly in clean engine oil for at
least five minutes before placing it in the cylinder head. This will ensure initial
lubrication over the full length of the cam follower roller pin, and is essential to
satisfactory cam follower performance. Rotating the cam roller during this period
will aid in introduction of oil to the cam roller pin.
(4) Repair. Replace damaged or defective cam followers and push rod assemblies as required.
(5) Installation.
(a) Assemble the lower spring seat, push rod spring, upper spring seat, and locknut on the push rod (figure 3-51).
(b) With the spring seat retainer in place in the cylinder head, slide the push rod and spring assembly into
position from the bottom of the cylinder head (fig. 3-52).
(c) Screw the push rod locknut down on the
upper end of the push rod as far as possible; then, screw the push rod into the clevis until the end of the rod is flush with or
above the inner side of the clevis.
(d) Lubricate the cam roller and cam follower body.
(e) Note the 1/8 inch oil hole in the bottom of the cam following. With this hole pointing away from the exhaust
valves and injectors, so that the hole is not covered by the cam follower guide, slide the cam follower into position from the
bottom of the head.
(f) Attach the follower guide to the cylinder head to hold the group of cam followers in place. Check to make sure
there is clearance between the cam followers and the cam follower guide. Tighten the guide bolts to 12-15 lb-ft torque.
CAUTION
Whenever a push rod has been disconnected from the rocker arm clevis, the push
rod must be threaded into the clevis until the end of the rod is flush with or above
the inner side of the clevis yoke at the time of reassembly, before the valve
clearance is adjusted. If this is not done, the valve may strike the piston (due to the
small clearance between the valve head and the piston head when the piston is at
top dead center) and thus be seriously damaged when the crankshaft is turned.
3-15. Exhaust Valves
a. Removal and Disassembly.
NOTE
Do not permit the cylinder head to rest on the cam followers.
(1) Remove the fuel injector of the appropriate cylinder.
(2) Place a block between the cylinder head and the bench to support the exhaust valves.
(3) Thread the spring compressor tool J 7455, into one of the rocker shaft bolt holes in the cylinder head.
(4) Apply pressure to the free end of the tool to compress the valve spring, then remove the two-piece tapered valve
lock. (1, fig. 3-45).
(5) Release the tool and remove the spring cap, valve spring, valve guide oil seal and spring seat.
(6) Turn the cylinder head over using care to keep the valves from dripping out.
(7) Number each valve to facilitate reinstallation in the same position, then withdraw the valves from the cylinder
head.
(8) Support the cylinder head, bottom side up, on two inch thick wood blocks.
(9) Drive the valve guide out from the bottom of the cylinder head with tool J 267.
CAUTION
The valve seat inserts are pressed into the cylinder head and, therefore, must be removed
as outlined in the following procedure to avoid damage to the head.
(10) Place the cylinder head on its side as shown in figure 3-55.
3-74
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