
English –
11
Troubleshooting
Acceleration and retardation
Does not
accelerate
Engine stalls
when throttle
released
Over rich
acceleration
Adjust L screw
Adjust H screw
Blocked air filter
Blocked fuel tank vent
Blocked fuel filter
Fuel line blocked
Loose or damaged fuel hose
Impulse channel blocked
Loose cover on carburettor
pump side
Faulty pump diaphragm
Leaking air intake hose (rubber)
Loose carburettor mounting
bolts
Needle valve set too low
Metering system incorrectly
assembled
Needle valve assembly sticking
Faulty diffuser jets
Blocked silencer
Adjust L screw
Adjust H screw
Faulty pump diaphragm
Needle valve set too high
Needle valve assembly sticking
Faulty diffuser jets
Adjust L screw
Adjust H screw
Blocked air filter
Faulty pump diaphragm
Faulty diffuser jets
Troubleshooting methods
In addition to the faults described in the above
table, trouble shooting can be carried out on
specific components or sub-systems of the
chainsaw. The various procedures are
described in the relevant sections, as follows:
•
Checking the operation of
the chain brake
Page 13
•
Measuring the resistance of
the stop plate
Page 15
•
Pressure testing the carburettor
Page 32
•
Pressure testing the decompression
valve
Page 41
•
Pressure testing the cylinder
Page 43
Adjust H screw
Blocked air filter
Blocked fuel tank vent
Blocked fuel filter
Fuel line blocked
Loose or damaged fuel hose
Impulse channel leaking
Impulse channel blocked
Loose cover on carburettor pump
side
Faulty pump diaphragm
Leaking air intake hose (rubber)
Loose carburettor mounting bolts
Needle valve set too low
Metering system damaged
Metering system incorrectly
assembled
Leaking control diaphragm/cover
plate
Needle valve assembly sticking
Blocked silencer
Adjust H screw
Blocked fuel tank vent
Blocked fuel filter
Impulse channel leaking
Impulse channel blocked
Loose cover on carburettor pump
side
Faulty pump diaphragm
Blocked air filter
Needle valve assembly sticking
Leak in metering system (air or fuel)
Metering system incorrectly
assembled
Loose diaphragm rivet
Hole in diaphragm
Leaking control diaphragm/cover
plate
Blocked fuel tank vent
Blocked fuel filter
Fuel line blocked
Loose or damaged fuel hose
Impulse channel leaking
Impulse channel blocked
Loose cover on carburettor pump
side
Faulty pump diaphragm
Leaking air intake hose (rubber)
Loose carburettor mounting bolts
Needle valve set too low
Leak in metering system (air or fuel)
Metering unit incorrectly
assembled
Loose diaphragm rivet
Hole in diaphragm
Leaking control diaphragm/cover
plate
Will not run
at full throttle
Low power
Will not
“four-stroke”
High rpm