English
► Stop the engine.
► Detach the spark plug socket.
► Upend the lawn mower.
► Remove the blade.
► Sharpen the blade. Observe the sharpening
angle and cool the blade,
Bluing of the blade during sharpening is not
permitted.
► Attach the blade.
► If anything is unclear: consult a STIHL special‐
ist dealer.
18 Troubleshooting
18.1
Remedying Lawn Mower Faults
Fault
Cause
Engine cannot
Control bar for mowing is not
be started.
pressed.
Fuel tank is empty.
Fuel line is blocked.
Inferior, dirty or old fuel in the
tank.
Air filter is dirty.
Spark plug socket is detached
from spark plug or ignition lead
is not properly fastened to
socket.
Spark plug is dirty, damaged or
electrode gap is incorrect.
Resistance at the blade is too
great.
Engine diffi‐
Lawn mower housing is
cult to start or
blocked.
engine power
deteriorating.
Cutting height is set too low or
rate of feed is too high.
Water in fuel tank and carburet‐
tor or carburettor is blocked.
Fuel tank is contaminated.
Air filter is dirty.
Spark plug is dirty.
Engine over‐
Engine oil level is too low.
heating.
Cooling ribs are dirty.
Lawn mower
Blade is damaged.
vibrates
excessively.
Blade is not correctly attached.
Grass is not
Blade is blunt or worn.
being cut
cleanly.
32
19.2.
Remedy
► Start engine as described in this instruction
manual.
► Refuel lawn mower.
► Consult a STIHL specialist dealer.
► Use fresh, good-quality unleaded petrol.
► Consult a STIHL specialist dealer.
► Connect spark plug socket.
► Check connection between ignition lead and plug.
► Clean or replace spark plug.
► Adjust electrode gap.
► Set a higher cutting height.
► Start engine in lower grass.
Clean lawn mower.
Adapt cutting height or mow more slowly.
Empty fuel tank, clean fuel line and carburettor.
Consult a STIHL specialist dealer.
Consult a STIHL specialist dealer.
Clean or replace spark plug.
Add or change engine oil as described in the engine
instruction manual.
Clean lawn mower.
Replace blade.
Attach blade.
Sharpen or replace blade.
17 Repairing
17.1
Repairing the Lawn Mower
The user should not repair the lawn mower or
blade themselves.
► If the lawn mower or blade is damaged: do not
use the lawn mower or blade and consult a
STIHL specialist dealer.
► If warning signs are illegible or damaged: have
the warning signs replaced by a STIHL spe‐
cialist dealer.
17 Repairing
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