THE FUEL SYSTEM AND GOVERNOR
33
NOTE: The pilot screw regulates how much of
this pre-mixed fuel/air emulsion is allowed to
enter the throat of the carburetor, to atomize
down-stream of the throttle plate. On current
production units, it is set at the factory and the
screw head is removed.
See Figure 4.20.
NOTE: The transition ports are fixed. They are
drilled into the throat of the carburetor, down-
stream of the venturi. They lie behind the brass
welch plug near the pilot screw.
13. Soak the Carburetor body in a suitable solvent
until clean.
NOTE: Ultrasonic cleaning using a suitable
water/detergent mixture will clean carburetors
safely and effectively.
14. Rinse it thoroughly.
15. Dry the carburetor body using compressed air.
16. Reassemble the carburetor and install it by fol-
lowing steps 1-8 in reverse order.
Figure 4.20
Transition ports Pilot port
Pilot screw
(before head
is removed)
17. Start the engine and check the idle RPM using a
tachometer.
18. Check the top no load speed of the engine.
NOTE: The top no-load speed of the engine is
3500 RPM’s
+ 100.
19. The top no-load speed is easily adjusted by
tightening/loosing the speed adjustment screw.
Tighten the screw to decrease speed and loosen
it to increase speed.
See Figure 4.21.
Figure 4.21
Adjustment screw
To Next Page
Loading...
Need help?
General
