Carburetor Synchronization - Mercury 40 Service Manual

Carburetor Synchronization

1. Remove attenuator cover (see section 3B,"Car-
buretor Removal").
2. Loosen screw of cam follower.
3. Loosen two (2) synchronizing screws located on
throttle levers of top and bottom carburetors.
4. Look into throats of carburetors and verify all
throttle shutters are completely closed. Tighten
synchronizing screws.
b
a
b
a - Screw-Cam Follower
b - Screws-Synchronizing
5. Recheck throttle shutters and make any neces-
sary adjustments.
6. Hold throttle arm so that idle stop screw is against
stop.
90-852572R1 JANUARY 1998
7. Place roller of cam follower against throttle cam
and adjust idle stop screw to align recessed mark
of throttle cam with center of cam follower roller.
Tighten locknut.
c
d
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f
a - Throttle Arm
b - Idle Stop Screw
c - Throttle Cam
d - Raised Mark
e - Locknut
f - Cam Roller
8. Hold throttle arm at idle position. Adjust cam fol-
lower so that a clearance of .005-.040 in.(0.13
mm-1.02 mm) exists between roller of cam fol-
lower and throttle cam. Tighten screw securing
cam follower.
a - Cam Follower
b - Screw
c - Roller
d - Throttle Cam
b
e
d
.005-.040 in.
c
b
a
ELECTRICAL - 2C-3
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a
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