Service manual

MERCARB 2 BARREL CARBURETOR SERVICE MANUAL NUMBER 26
Page 5B-6 90-861329--1 MARCH 1999
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
a
b
Needle and Seat Assemblies
a-Spring Loaded Type Needle (Kit 3302-9029)
b-Solid Type Needle (Kit 3302-9407)
Adjustable Accelerator Pump Lever
This new 3-holed lever will allow you to change the amount of fuel delivered to the engine
by the accelerator 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
a
c
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 “bogging” problems with this 3-holed lever,
providing the “bogging” is caused by the carburetor. When installing 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 “Specifications.”
INDEX