Mercury 75 Service Manual page 116

CARBURETOR/OIL PUMP SYNCHRONIZATION
IMPORTANT: Some engines may have an addi-
tional stamped mark (d) which SHOULD NOT be
used.
1. While holding throttle arm at idle position, adjust
length of link rod so that stamped mark of oil
pump body aligns with stamped mark of oil pump
lever.
a
c
a - Link Rod
b - Mark of Oil Pump Body
c - Mark of Oil Pump Lever
d - Mark NOT Used
TIMING ADJUSTMENTS
CAUTION
Engine can be timed while cranking engine with
starter motor. To prevent engine from starting
when being cranked, all spark plugs should be
removed.
NOTE: If initial timing adjustments are made without
engine running, then final timing checks should be
made with engine running due timing advance char-
acteristics of ignition system. Maximum engine RPM
required to check maximum timing advance is 3000
RPM.
1. Insert Spark Gap Tool (91-63998A1) in no. 1 (top)
cylinder spark plug boot and attach alligator clip
to good ground.
2. Remove throttle cable barrel from barrel retainer.
90-830234R3 DECEMBER 1997
IDLE TIMING ADJUSTMENT
Before cranking engine, keep clear of propeller,
as it may rotate.
IMPORTANT: To accurately time engine at crank-
ing speed, a fully charged battery must be used.
1. Connect timing light to no. 1 (top) spark plug lead.
2. Shift engine into neutral.
3. Holding throttle arm at idle position, crank engine
with starter motor and adjust idle timing screw to
align 2 degrees BTDC timing mark of flywheel
b
with timing pointer.
d
22977
a - Idle Timing Screw
WARNING
a
ELECTRICAL - 2C-7
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