Carburetor And Fuel System - Westerbeke 9.0 BCG Technical Manual

CARBURETOR AND FUEL SYSTEM
Carburetor
The carburetor is a single barrel down draft type with a metal screened air intake filter which is cleanable.
The carburetor has two metering jets, one of which is adjustable (the idle mixture). The other fast running
jet is set at the factory and will accept no adjustment.
Any adjustment to the idle mixture jet should be done with the engine warmed up and without any load on
the generator.
Carburetor Adjustment
1. Idle Mixture Jet
Disconnect the throttle linkage arm from the governor control arm and reduce the engine's speed with
the idle stop screw. Turn the idle mixture screw clockwise (in) until the engine skips; back the screw
out (counterclockwise) slowly until the engine smooths then skips again; then turn the screw clockwise
(in) one-quarter to one-half of a turn. The idle mixture should be satisfactory at this setting.
NOTE: At idle speed, oil pressure will be lower than the rating of the oil pressure switch. Jump
this switch to prevent engine shutdown at idle speed.
2. Run Mixture Jet
This mixture jet is presized at the factory and is not adjustable. The idle mixture jet adjustment can
be made in the 1800 rpm range to improve engine performance. Refer to the "Governor Adjust-
ments" section of this manual for instructions on how to adjust the engine's speed, page 163-164.
165 Westerbeke Generators