Husqvarna 455 Rancher II - Page 57

English – 57
Uneven idling
Too much fuel at
idle speed
Starting
Idling (low speed)
Idling (low speed) (continued)
Leaking inlet hose (rubber)
Loose clamping screws car-
buretor
Loose or faulty fuel pipe
Blocked fuel lter
Blocked fuel line
Tank ventilator blocked
Throttle valve shaft is inert
Throttle stay is binding
Defective throttle return spring
Bent valve axle stop
Faulty diffuser jet
Worn lever arm in the control
system
Leaking control diaphragm/
cover plate
Does not idle
Too high idling
speed
8.1 Troubleshooting
The different faults which may occur on the chain saw are divided into four groups. Within each group, the
possible operating faults are listed to the left while the probable fault alternatives are listed to the right.
The most likely fault is listed rst, etc. See separate instruction for AutoTune troubleshooting.
Difcult to start
The carburetor
leaks fuel
Floods when the
engine is not
running
Air lter blocked
Choke does not work
Worn choke axle
Worn choke valve
Blocked fuel lter
Blocked fuel line
Piston ring is stuck
Blocked impulse channel
Loose or faulty fuel pipe
Hole in the membrane
Control system is binding
Control system set too high
Leaking control system (air or
fuel)
The cover on the carburetor
pump side is loose
Control system set too high
Control system is binding
Blocked fuel lter
Blocked fuel line
Leaking inlet hose (rubber)
Loose clamping screws car-
buretor
Worn throttle valve shaft
Loose throttle valve screw
Worn throttle valve
Leaking control system (air or
fuel)
The control system’s center
knob is worn
Hole in the membrane
Leaking control diaphragm/
cover plate
Leaking crankcase
Leaking control diaphragm/
cover plate
Troubleshooting