TM 5-3810-300-24&P-3
Examine the cam follower bores in the cylinder head to
make sure they are clean, smooth and free of score
marks. If necessary, clean-up the bores.
Inspect the push rods and spring seats for wear. The
current push rods have milled wrench flats and a bright
"turned" finish and the lower spring seats are serrated
along the push rod contact surfaces (Fig. 6).
CAUTION: When replacing a push rod or lower spring
seat, do not use a plain spring seat (Fig. 6) with a
current type push rod. Any other combination of spring
seat and push rod may
be used.
Examine the cam follower springs for wear or damage
and check the spring load. Replace a spring when a
load of less than 172 lbs. (765 N) will compress it to a
length of 2.125". Use spring tester J 9666 and an
Fig. 5 Cam Roller Clearances
accurate torque wrench to check the spring load (Fig. 7).
Examine the cam follower rollers for scoring, pitting or
flat spots. The rollers must turn freely on their pins.
Replace Cam Roller and Pin
Measure the total diametric clearance and side
clearance. Install a new roller and pin if the clearances
To replace a cam roller and pin, proceed as follows:
exceed those specified in Fig. 5. Cam followers
stamped with the letter "S" on the pin, roller and follower
CAUTION: Do not attempt to bore out the
body are equipped with an oversize pin and roller. The
legs of a standard cam follower for an
same clearances apply to either a standard or oversize
oversize pin.
cam follower assembly.
I.
Clamp fixture J 5840 securely in a vise as shown in
Examine the camshaft lobes for scoring, pitting or flat
Fig. 8. Then place the cam follower in the groove in
spots. Replace the camshaft if necesary.
Check the cam follower-to-cylinder head clearance. The
Fig. 6 - Comparison of Push Rods and Lower Spring
Clearance must not exceed .006 " with used parts.
eats
Fig. 6 - Comparison of Push Rods and Lower Spring Seats
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