remove main bearing caps (6) and lower half of main
(a) Attach a dial indicator to the cylinder block
bearing inserts (7).
and position so that the foot contacts the end of the
remove main bearing cap (10) and lower half of
(b) Press camshaft as far into the cylinder
center main bearing insert (11).
block as it will go.
(10) Lift crankshaft (12) from cylinder block and
(c) Set dial indicator to "zero" position
remove upper half of main bearing inserts
(d) Move camshaft as far forward as it will go.
(e) Check indicator reading. Reading shall not
Conspicuously mark each main bearing cap
as to position to aid at assembly.
(f) If reading exceeds specified limit, remove
camshaft and replace thrust plate.
(3) Check backlash between camshaft drive gear
(1) Do not remove crankshaft gear (13) and
and crankshaft gear. Backlash shall be 0.0010 to
woodruff key (14) unless inspection reveals damage
0.0030. If backlash is not within specified limits, both
and replacement is necessary.
camshaft drive gear and crankshaft gear must be
(2) Remove retaining ring (15) and piston pin (16)
to remove piston assembly (17) from connecting rod
3-55. Crankshaft, Connecting Rods and
(3) Do not remove bushing (19) unless inspection
reveals damage and replacement is necessary.
(4) Remove compression ring (21), scraper rings
(22) and oil control ring (23) from piston (24). Discard
(2) Remove flywheel and flywheel housing (para
c. Cleaning, Inspection, and Repair.
(3) Remove cylinder head and rocker arm
(1) Clean all parts in dry cleaning solvent
(Federal Specification P-D-680) and dry with filtered
(4) Using a ridge cutter, remove the ridge from
the top of each cylinder.
( 2 ) Clean all oil passages in crankshaft and
connecting rods with a wire brush.
rod bearing caps (2) and lower half of connecting rod
bearing insert (3).
Use care to avoid damaging ring grooves in
(6) Using a wooden dowel, push pistons and
connecting rods out top of cylinder block).
(3) Scrape carbon deposits from top and ring
groove of piston.
Rotate crankshaft to simplify removal if
( 4 ) Inspect crankshaft for cracks, nicks and
s c r a t c h e s on bearing journals or other damage.
(7) Remove upper half of connecting rod bearing
Remove minor nicks and scratches from bearing
journals with crocus cloth. Clean to remove abrasive
( 5 ) Perform magnetic particle inspection of
Keep connecting rod bearing caps with the
c r a n k s h a f t in accordance with established proc-
connecting rod horn which they were