7 Bolt, thrust plate
8 Bearing, sleeve, front
Lockwasher, thrust plate bolt
9 Bearing, sleeve, intermediate front
10 Bearing, sleeve, intermediate rear
Nut, self-locking, gear-to-camshaft
11 Bearing, sleeve, rear
Figure 7. Camshaft, exploded view.
valves, using above procedure.
Grasp valve on unworn portion of stem, close to head,
If any margin is below
and grind valve as follows:
minimum, discard valve and
(a) Position chuck so that contact is
install a new one.
just barely made between
c. Installation. Reverse procedure in a above.
grinding wheel and valve face
d. Adjustment. Refer to TM 10-3980-20.
Feeding. wheel slowly into
valve, make a very light cut
around entire valve face,
23. Valve Guides
always keeping valve in contact
a. Inspection and Cleaning.
with grinding wheel. If the cut
(1) Remove valve ((1) through (6), par. 22).
removes metal from one-half of
(2) Inspect guide for wear and carbon
valve face or less, inspect
If carbon is excessive,
chucking (gripping) of valve. If
clean out with brush and/or proper
inspection reveals valve is
If guide is worn
squarely mounted, valve is
excessively so that valve stem
discarded. If mounting is faulty,
specifications (par. 7), replace guide
check valve squarely and
(b and c below).
repeat operation. When face is
(1) With valve removed (a above), remove
valve lifter adjusting screw.
alinement is satisfactory.
(2) Using a suitable drift, knock valve guide
After first cut has proved
(5, fig. 9) down until lower end
approaches valve lifter, and remove
grinding operation. Do not take
heavy cuts or remove more
(3) Repeat procedures in (1) and (2) above
metal than necessary to remove
for the remaining guides
c. Installation. Mark point on driving mandrel 1
When valve face has been
15/32 inches from driving end, position new valve guide,
ground, remove valve and
and drive in until top of guide is 1 15/32 inches from top
check margin for minimum
of cylinder block.
thickness of 3/64 inch at any
point. If margin is satisfactory,
place valve in its position in
rack and grind remaining