WM, Workshop Manual, K650, K700, K950, K1250, 2001-06, Power ...

3
Fuel system
Walbro WG 9
A
C
B
Mod. 1250
The carburettor on this model is of Walbro
manufacture.
The service method is the same as for the
Tillotson carburettor. Note the small O-
ring (A) placed on the compensation
device.
This carburettor does not have a speed
limiter either.
A = O-ring
B = Main nozzle
C = Main jet (high speed)
D = Low speed needle
E = Adjuster screw for idle speed
F = Fuel screen
The main jet (C) can be dismantled for
cleaning or replacement.
E
D
F
T
H
L
Fit the carburettor on the engine in the reverse order to dismantling. Use new gaskets
Check that the gaskets are turned the right way round so that the impulse channel is
not blocked.
Carburettor setting (not EPA models)
! WARNING!
When test running the engine in connection with the adjustment of the
carburettor the clutch, cutting arm and cutting disc must always be fitted.
Otherwise there is a risk that the clutch may release and cause serious
personal injury.
Function
The purpose of the carburettor is to supply a combustible mixture of air and fuel to the
cylinder.
The volume of this mixture is regulated with the throttle control.
The composition of the mixture of air and fuel is regulated with the adjustable nozzles
”H” and ”L”.
The carburettor should be adjusted if:
● The cutting disc rotates when the engine is idling.
● The engine speed does not go down to idle from full throttle within 3-5 seconds.
● The engine does not run on idle.
● The engine does not respond quickly to the throttle.
● The engine seems to lack power.
32
NOTE!
EPA models have carburettors with fixed jets "H" and "L". This means that they can not
be adjusted