Mercury 305 CID, Service Manual, Page: 249 / 967

ENGINES - 3A-57 90-823225--1 1096
d. Remove the bearing cap and using the scale
on the gauging plastic envelope, measure the
gauging plastic width at the widest point as
shown.
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6. If the clearance exceeds specifications, select a
new, correct size bearing and remeasure the
clearance.
Be sure to check what size bearing is being re-
moved in order to determine proper replacement
size bearing. If clearance cannot be brought to
within specifications, the crankpin will have to be
ground undersize. If the crankpin is already at
maximum undersize, replace crankshaft.
7. Coat the bearing surface with oil, install the rod
cap.
a. All engines except Gen+: Torque nuts to 45
Lb. Ft. (61 N·m).
b. Gen+: Torque nuts to 20 Lb. Ft. (27 N·m)
8. When all connecting rod bearings have been in-
stalled, tap each rod lightly (parallel to the crank-
pin) to make sure they have clearance.
9. Measure all connecting rod side clearances (see
“Specifications”) between connecting rod caps
as shown.
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Connecting Rod/Piston
Assembly
Removal
1. Remove as outlined:
a. Oil pan and dipstick tube.
b. Baffle and oil pump.
c. Distributor and intake manifold.
d. Cylinder heads.
2. Use a ridge reamer to remove any ridge and/or
deposits from upper end of cylinder bore.
IMPORTANT: Before ridge and/or deposits are re-
moved, turn crankshaft until piston is at bottom
of stroke and place a cloth on top of piston to col-
lect cuttings. After ridge and/or deposits are re-
moved, turn crankshaft until piston is at top of
stroke, then remove cloth and cuttings.