Husqvarna 243RJ Workshop Manual page 32

4
The centrifugal clutch has the task of transferring the power from the engine to the cutting
equipment's drive axle. As the name implies, it works according to a centrifugal principle.
This means the clutch's friction shoes are thrown outwards towards the clutch drum at a certain
engine speed. When the friction against the drum is suffi ciently great it drives the drive shaft at
the same speed as the engine.
Some slipping occurs between the clutch and the clutch drum when accelerating as well as in the
reversed situation when the cutting equipment jams. Thereby preventing abnormal load changes
on the crankshaft.
The engagement speed has been carefully tested so that the engine can idle without the cutting
equipment's drive shaft rotating.
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Centrifugal clutch
Centrifugal clutch
Dismantling
Remove the cover over the air fi lter.
Separate the short-circuit cables and
disconnect the throttle cable.
Remove the screws holding the clutch
cover and lift off the assembly.
Stop the piston from moving using, for ex-
ample, a piece of trimmer cord fed down
through the spark plug hole.
Dismantle the centrifugal clutch.
Centrifugal clutch
Dismantling
1. Remove the cover over the air fi lter.
2. Separate the short-circuit cables.
3. Disconnect the throttle cable from the
carburettor.
4. Remove the 4 screws holding the
clutch cover against the fan housing
cover.
5. Lift off the entire assembly.
Remove the spark plug and stop the
piston from moving by feeding a 200 mm
long piece of trimmer cord (Ø 3 mm), for
example, down through the spark plug
hole so that it is positioned between the
piston and the top of the cylinder.
Bend the end of the cord so it is easier to
position on top of the piston.
The cord should not be pushed out
through any port in the cylinder wall!
Remove both screws holding the centrifu-
gal clutch.
Lift off the clutch.
Note the fl at washers that are behind the
clutch shoes.