ARMY TM 9-2815-253-24
AIR FORCE TO 38G1-93-2
MARINE CORPS TM 2815-24/3
SECTION X. ENGINE SUBASSEMBLY MAINTENANCE
3-25. CYLINDER COVER.
3-25.1. Removal. Remove two nuts (1, FIGURE 3-27) and performed packings (2) securing each valve cover (3) to
cylinder head; remove cover (3) and gasket (4). Discard gasket (4) and performed packings (2).
3-25.2. Inspection.
a.
Inspect cover for cracks, dents, or any other damage.
b.
Inspect nuts for rounded hex comers or thread damage.
3-25.3. Installation.
a.
Remove any traces of old gasket from cylinder head and valve covers (3, FIGURE 3-27) mating surfaces.
b.
Ensure mating surfaces are clean and dry.
c.
Position each valve cover (3) with new gasket (4) on cylinder head and secure with two nuts (1) and new
preformed packings (2). Tighten nuts (1) to 78 in-lbs (8.8 Nm).
3-26. ROCKER LEVER.
3-26.1. Removal.
a.
Remove cylinder covers. Refer to paragraph 3-25.1.
b.
Remove nut (5, FIGURE 3-27) securing rocker lever (6) to cylinder head bolt (7); remove rocker lever.
c.
Remove pushrod (9).
d.
Repeat steps b and c for remaining rocker levers and pushrods.
e.
Do not remove cylinder head bolt (7) and spacer (8) unless damaged or cylinder head is being removed.
3-26.2. Inspect and Measure.
a.
Check pushrod (9, FIGURE 3-27) as follows:
(1)
Lay pushrod on a surface plate.
(2)
Roll pushrod along surface plate checking for curvature with a feeler gage. Normal reading should be
0.008 in. (0.2 mm) or less.
(3)
Inspect both ends of pushrod for excessive wear or damage. If excessive wear or damage is found,
replace pushrod.
b.
Inspect rocker lever valve stem contact surface for step wear and scoring. If contact surfaces have light step
wear or scoring, they may be honed with an oil stone. If step wear or scoring is severe, rocker lever must
be replaced.
3-26.3. Installation.
CAUTION
Ensure that no piston is at TDC when Installing pushrods. Failure to follow this procedure could
cause damage to pushrods.
a.
Lightly oil pushrod (9, FIGURE 3-27) with engine lubricating oil (MIL-L-2104) and install it in cylinder head.
Ensure pushrod does not interfere with cylinder head clearance hole.
b.
Lightly oil rocker lever (6) and install it on cylinder head bolt (7). Secure with nut (5) finger tight.
c.
Gradually tighten nut (5) until heel of rocker lever (6) makes contact with ball end of pushrod (9). Ensure rocker
lever is centered over valve stem.
3-47
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