Adjusting The Carburettor - Westfalia FM BK 4545 T Original Instructions Manual

Maintenance

Adjusting the Carburettor

The carburettor on the saw chain has been factory adjusted, but
may require fine tuning due to change in operating conditions.
The carburettor should only be adjusted by a professional.
Incorrect tuning may result in damage to the chain saw.
The carburettor must be adjusted with attached guide bar and saw
chain.
Before adjusting the carburettor make sure the air and fuel filters are
clean and the fuel mixture is clean and correctly mixed.
T-Idle Screw is for adjusting the idle speed. Turning the T-screw
clockwise will give the engine a higher idle speed; turning the screw
counter clockwise will give a lower idle speed.
The H Adjusting Screw is for adjusting the High Seed Jet and the
L Adjusting Screw is for adjusting the Low Speed Jet.
Air and fuel are mixed in the
T-Screw
carburettor. The L and H-jets are used
to adjust the supply of fuel to match
the rate that air is admitted. If the
screws are screwed clockwise the
air/fuel ratio becomes leaner (less
fuel) and if the screws are turned
counter clockwise the ratio becomes
richer (more fuel).
First adjust the L jet, then the T-Idle
screw and finally the H jet.
Fine Adjustment of the L jet
Carefully turn the L and H jets up to
the end by turning clockwise. Turn the
screws counter clockwise by 1 Turn.
This complies with the basic setting.
L-Screw
The basic setting is carried out by the
H-Screw
factory.
Now start the machine according to the starting instructions and let it
warm up for 10 minutes. Do not run the chain saw witch full speed for
more than 10 seconds! If the chain rotates during idling speed, turn the
T-Idle screw counter clockwise until the chain stops.
22