5B - 4 - MERCARB 2 BBL CARBURETOR
90-816462 2-695
Important Service
Information
Flooding at Idle RPM
If your engine floods at idle RPM, check the following:
1. Problem in ignition system causing engine to run
rough.
2. Idle mixture screw adjusted incorrectly.
3. Bad needle and seat.
4. Incorrect float level drop.
Needle/Seat Change
If the preceding steps failed to correct the problem,
change the needle/seat to the other type. MerCarbs
are equipped with either the solid or the spring loaded
needle.
72290
b
a
a - Spring Loaded Type Needle (Kit 3302-9029)
b - Solid Type Needle (Kit 3302-9407)
Needle and Seat Assemblies
Adjustable Accelerator Pump Lever
This new 3-holed lever will allow you to change the
amount of fuel delivered to the engine by the acceler-
ator pump. The hole closest to the lever’s shaft will
give the same amount of fuel as the single hole lever
did. The center hole gives approximately 0.5 cc less
fuel and the hole farthest away will give about 1.0 cc
less fuel.
73131
c
a
b
a - Full Accelerator Pump Stroke
b - 0.5 cc Less Fuel per Stroke
c - 1.0 cc Less Fuel per Stroke
The technician should be able to correct most “bog-
ging” problems with this 3-holed lever, providing the
“bogging” is caused by the carburetor. When instal-
ling the 3-holed lever, remove any metal ball that
someone may have put in the accelerator pump well
to limit pump travel. Also, make sure that the duration
spring on the accelerator pump is stock and hasn’t
had several coils cut off. Make sure the venturi cluster
is the correct one as outlined previously under “Speci-
fications.”
Description
This MerCarb carburetor is a two bore carburetor and
has a separate fuel feed for each venturi. This model
also is equipped with an electric choke. A removable
venturi cluster (secured to float bowl assembly) has
the calibrated main well tubes and pump jets built into
it. The venturi cluster is serviced as a unit. The ser-
viceable main metering jets are bleeds to properly
meter the correct fuel/air mixture to the engine.
Summary of Contents for 13
Page 1: ...13 Printed in U S A 90 816462 2 695 1995 Brunswick Corporation GM 4 Cylinder MARINE ENGINES ...
Page 2: ...90 816462 2 695 0 ...
Page 7: ...1 A IMPORTANT INFORMATION GENERAL INFORMATION 72000 ...
Page 15: ...1 B 50617 IMPORTANT INFORMATION MAINTENANCE ...
Page 36: ...1 C IMPORTANT INFORMATION TROUBLESHOOTING ...
Page 74: ...2 A 50633 REMOVAL AND INSTALLATION 4 CYL ALPHA ONE DRIVE ...
Page 88: ...3 A 26790 ENGINE 181 CID 3 0L 4 CYLINDER GM ENGINE ...
Page 137: ...4 A 72079 ELECTRICAL SYSTEMS STARTING SYSTEM ...
Page 170: ...4 B 71855 ELECTRICAL SYSTEMS IGNITION SYSTEM ...
Page 197: ...ELECTRICAL SYSTEMS CHARGING SYSTEM 4 C 72078 ...
Page 237: ...4 D 72747 ELECTRICAL SYSTEMS INSTRUMENTATION ...
Page 250: ...4 E 72938 ELECTRICAL SYSTEMS WIRING DIAGRAMS ...
Page 264: ...5 A FUEL SYSTEM FUEL PUMP ...
Page 271: ...5 B 72681 FUEL SYSTEM MERCARB 2 BARREL CARBURETOR ...
Page 300: ...6 A 50628 COOLING SYSTEM SEAWATER COOLED MODELS ...
Page 309: ...6 B 73665 COOLING SYSTEM CLOSED COOLING MODELS ...
Page 325: ...C 6 EXHAUST SYSTEM MANIFOLD ...
Page 331: ...7 A 71317 POWER STEERING PUMP ...