Section 12 Troubleshooting Guide - Makita PLM4627N Instruction Manual

12. TROUBLESHOOTING GUIDE
PROBLEM
Engine does not start.
Engine difficult to start or loses
power.
Engine operates erratically.
Engine idles poorly.
Engine skips at high speed.
Engine overheats.
Mower vibrates abnormally.
PROBABLE CAUSE
Throttle choke not in the correct position
for the prevailing conditions.
Fuel tank is empty.
Air cleaner element is dirty.
Spark plug loose.
Spark plug wire loose or disconnected
from plug.
Spark plug gap is incorrect.
Spark plug is defective.
Carburetor is flooded with fuel.
Faulty ignition module.
Dirt, water, or stale fuel tank.
Vent hole in fuel tank cap is plugged.
Air cleaner element is dirty.
Spark plug is defective.
Spark plug gap is incorrect.
Air cleaner element is dirty.
Air cleaner element is dirty.
Air slots in engine shroud are blocked.
Cooling fins and air passages under
engine blower housing are blocked.
Gap between electrodes of spark plug is
too close.
Cooling air flow is restricted.
Incorrect spark plug.
Cutting assembly is loose.
Cutting assembly is unbalanced.
CORRECTIVE ACTION
Move throttle choke to correct position.
Fill tank with fuel: refer to ENGINE
OWNERS MANUAL.
Clean air cleaner element: refer to
ENGINE OWNERS MANUAL.
Tighten spark plug to 25-30 Nm.
Install spark plug wire on spark plug.
Set gap between electrodes at 0.7 to
0.8 mm.
Install new, correctly gapped plug: refer
to ENGINE OWNERS MANUAL.
Remove air cleaner element and pull
starter rope continuously until carburetor
clears itself and install air cleaner
element.
Contact the service agent.
Drain fuel and clean tank. Fill tank with
clean, fresh fuel.
Clean or replace fuel tank cap.
Clean air cleaner element.
Install new, correctly gapped plug: refer
to ENGINE OWNERS MANUAL.
Set gap between electrodes at 0.7 to
0.8 mm.
Clean air cleaner element: refer to
ENGINE OWNERS MANUAL.
Clean air cleaner element: refer to
ENGINE OWNERS MANUAL.
Remove debris from slots.
Remove debris from cooling fins and air
passages.
Set gap between electrodes at 0.7 to
0.8 mm.
Remove any debris from slots in shroud,
blower housing, air passages.
Install RC12YC or QC12YC spark plug
and cooling fins on engine.
Tighten blade.
Balance blade.
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