Trouble Shooting - Husqvarna 335XPT Workshop Manual

Trouble shooting schematic
Faults that can develop on the chain saw are divided into four
groups as follows. In each category, possible malfunctions are
shown on the left, with a list of possible faults on the right. The
most probable fault is given first and so on.
Starting
Difficult starting Adjust L-screw
Air filter blocked
Choke not working
Worn choke shaft
Worn choke valve
Fuel filter blocked
Fuel line blocked
Piston ring seized
Blocked impulse channel
Carburettor leaking Loose or faulty fuel pipe
fuel
Hole in diaphragm
Worn needle valve/needle
Control system sticking
Control system set too high
Leak in control system (air or fuel)
Loose cover on carburettor
pump side
Flooding when the
Worn needle valve
engine is not running
Control system set too high
Control system sticking
Idling (low rpm)
Will not idle Adjust L-screw
Leaking manifold (rubber)
Loose carburettor mounting bolts
Loose or faulty fuel pipe
Fuel filter blocked
Fuel line blocked
Fuel tank ventilator blocked
Throttle lever shaft stiff
Throttle cable sticking
Defective throttle return spring
Bent throttle lever shaft stop
Faulty diffuser jets
Idling too rich Adjust L-screw
Worn needle valve/needle
Control system set too high
Worn throttle lever in control system
Leaking control diaphragm/cover plate
Control system sticking
10
– English

TROUBLE SHOOTING

Idling (low rpm) (cont.)
Idles when L-screw
is closed
Idling uneven
L-screw requires
constant adjustment
Too much fuel when
idling
Worn needle valve/needle
Leaking control diaphragm/cover plate
Control system sticking
Worn throttle lever in control system
Faulty diffuser jets
Fuel filter blocked
Fuel line blocked
Leaking manifold (rubber)
Loose carburettor mounting bolts
Worn throttle valve shaft
Loose throttle valve screw
Worn throttle valve
Control system sticking
Leak in throttle system (air or fuel)
Control diaphragm centre knob is
worn
Hole in diaphragm
Leaking control diaphragm/cover plate
Crankcase leaking
Fuel line blocked
Control system set too high
Control system sticking
Control system (air or fuel)
Leaking control diaphragm/cover plate
Faulty diffuser jets
Crankcase leaking
Control system set too high
Control system sticking
Control system damaged
Worn needle valve
Leaking control diaphragm/cover plate
Control system incorrectly assembled