Husqvarna T540 XP Workshop Manual page 64

Troubleshooting
8.1 Troubleshooting
The different faults which may occur on the chain saw are divided into four groups. Within each group
possible operating faults are listed to the left while the probable fault alternatives are listed to the right.
The most likely fault is listed first, etc.
See separate instruction for AutoTune troubleshooting.
Starting
Starting Clogged air filter
difficulties Choke does not work
Worn choke shaft
Worn choke valve
The fuel filter is clogged
The fuel line is clogged
Piston ring is stuck
Blocked impulse channel
The carburettor Loose or defective fuel hose
leaks fuel Hole in the membrane
Control system is jamming
Control system set too high
Leaking control system (air or
fuel)
The cover on the carburettor
pump side is loose
Floods when the Control system set too high
engine is not Control system is jamming
running
Idling (low speed)
Leaking inlet hose (rubber)
Does not run
Loose clamping screws
when idling
carburettor
Loose or defective fuel hose
The fuel filter is clogged
The fuel line is clogged
Tank venting clogged
The throttle valve shaft is slug-
gish
Throttle stay is jamming
Defective throttle return spring
Bent valve shaft stop
Faulty diffuser jet
Worn lever arm in the control
Too high idling
system
speed
Leaking control diaphragm/
cover plate
64
– English
Idling (low speed) (cont.)
Irregular idling
The fuel filter is clogged
The fuel line is clogged
Leaking inlet hose (rubber)
Loose clamping screws
carburettor
Worn throttle valve shaft
The throttle valve screw is
loose
The throttle valve is worn
Leaking control system (air
or fuel)
The control system's centre
knob is worn
Hole in the membrane
Leaking control diaphragm/
cover plate
Crankcase leak
Leaking control diaphragm/
Too much fuel
cover plate
on idling