(4) Inspect the crankcase for cracks, breaks or
other defects. Replace the crankcase if defective.
Mark connecting rod and piston to
(5) Measure the ring grooves in the piston for
wear. Replace piston if tolerance is greater than noted in
m. Reassembly and Installation. Crankshaft and
piston on wooden block and tap out piston pin (2).
(1) Refer to figures 5-21 thru 5-25 and reassemble
Do not remove the connecting rod
and install the pistons, piston rings, expander spacer,
bushings, if inspection reveals a
connecting rods and crankshaft into crankcase taking the
defect, they must be replaced as an
(2) When installing piston rings expand them
k. Oil Pump Cover Disassembly.
carefully and sufficiently to allow the ring to slide freely
over the piston to the position required. Starting with
and lift off valve cover (6) from body (14).
bottom piston rail ring (5, fig. 5-23) install piston rings
(2) Remove cover seal (7) from valve cover.
and expanded spacer in their proper grooves. Stagger
(3) Remove spring (8), check valve (9), pin (10)
ring gaps so that they are not lined up.
and pin seal (11) from body.
(4) Lubricate each piston and connecting rod
which attach body (14) onto oil pump cover (17).
assembly with a light coat of engine oil before in-stalling
(5) Remove body (14) and disassemble piston
(15) and bellofram (16).
(5) Torque connecting rod bolts as indicated in
(6) The pipe plug (3) does not require removal
unless a defect is noted.
(6) Lubricate bearing cones (2, fig. 5-25) and in-
l. Cleaning and Inspection.
stall onto crankshaft and into crankcase, then in-stall two
bearing cups into the front and rear of crankcase. Check
Drycleaning solvent, P-D-680, used
to clean parts is potentially
(7) Apply a light coat of engine oil to inside wall of
cylinder, install new cylinder gasket and cylinder over
Avoid repeated and
piston, secure with capscrews (1, fig. 5-19) and torque
prolonged skin contact. Do not use
to 47 foot-pounds (6.5 kg/m).
near open flame or excessive heat.
(8) Install new front oil seal (3, fig. 5-24) into
Flash point of solvent is 100 degrees
F to 138 degrees F (38 degrees C to
(9) Install new oil relief valve nylon ball (15, fig. 5-
59 degrees C).
22), spring (14), retainer (13) and roll pin (12) if removed
(1) Clean all metal parts in P-D-680 cleaning
for inspection, or found defective.
solvent and dry thoroughly.
(10) Install shims (9, 10, and 11) and rear retainer
(2) Inspect the crankshaft for cracks, scores, and
(7) onto crankcase.
distortion. If defects are noted replace crankshaft with a
(11) Install new pump cover O-ring into grooves on
new crankshaft assembly.
(12) Install roll pin (6) and insert (5) into rear
A crankshaft assembly comes
complete with two matched bearing
(13) Install springs (4), vanes (3) into rotor (2), and
carefully into rear retainer.
(3) Inspect the crankshaft bearing cones for rough,
(14) Assemble oil pump cover (17, fig. 5-21) on-to
pitted, or scored rollers. Replace a defective bearing.
rear retainer and secure with screws (1) and