Fault:
Engine does not start
Possible cause:
– Motorstop lever not pressed.
– No fuel in tank.
– Fuel line blocked.
– Inferior, dirty or old fuel in tank.
– Air filter dirty.
– Spark plug socket detached from spark
plug; ignition lead not properly fastened
to socket.
– Spark plug dirty or damaged; incorrect
electrode gap.
Remedy:
– Press motorstop lever to handlebar and
hold. (
11.1)
– Refill fuel tank. (
7.6)
– Clean fuel line.
,
– Always use fresh, good quality fuel,
unleaded petrol; clean
carburettor.
,
– Clean air filter.
,
– Connect spark plug socket; check
connection between ignition lead and
socket.
,
– Clean or replace spark plug; adjust
electrode gap.
Fault:
Starting problems or deteriorating engine
power.
Possible cause:
– Lawn mower housing blocked.
– Mowing at an excessively low cutting
height or propulsion speed is too high in
relation to the cutting height.
– Water in fuel tank and carburettor;
carburettor blocked.
– Fuel tank contaminated.
0478 111 9924 C - EN
– Air filter dirty.
– Spark plug dirty.
Remedy:
– Clean lawn mower housing (detach
spark plug socket!). (
12.1)
– Select a higher cutting height or reduce
the pushing speed. (
8.5)
– Empty fuel tank, clean fuel line and
carburettor.
– Clean fuel tank.
– Clean air filter.
– Clean spark plug.
Fault:
Engine overheating.
Possible cause:
– Oil level in engine too low.
– Cooling ribs dirty.
Remedy:
– Change engine oil. (
12.5)
– Clean cooling ribs. (
12.1)
Fault:
Excessive vibration during operation.
Possible cause:
– Cutting unit defective.
– Engine mounting loose.
Remedy:
– Check mowing blade, blade shaft and
blade fastening (blade fastening screw
and retaining washer), and repair if
necessary.
– Tighten engine mounting bolts.
Fault (MB 4 RT, MB 4 RTP):
No drive when self-propulsion lever is
actuated
Possible cause:
– Self-propulsion cable damaged
(e.g. kinked)
Remedy:
– Replace cable
Fault:
Poor cut, lawn turning yellow
Possible cause:
– Mowing blade is blunt or worn,
Remedy:
– Sharpen or replace the mowing blade
(
12.3), (
12.4),
20. Service schedule
20.1 Handover confirmation
45