Dolmar MS-4300.4R, Original Instruction, Page: 29 / 228

29
TROUBLESHOOTING
Before making a request for repairs, check for trouble by yourself. If any abnormality is found, control your machine according to the description
of this manual. Never tamper or dismount any part contrary to the description. For repairs, contact Authorized Service Agent or local dealership.
State of abnormality Probable cause (malfunction) Remedy
Engine does not start.
I-O switch is set to STOP. Set the I-O switch to OPERATION.
Failure to operate primer pump. Push 7 to 10 times.
Low pulling speed of starter rope. Pull strongly.
Lack of fuel. Feed fuel.
Clogged fuel filter. Clean.
Bent fuel tube. Straighten fuel tube.
Deteriorated fuel.
Deteriorated fuel makes starting more difficult.
Replace with new fuel. (Recommended
replacement: 1 month)
Excessive suction of fuel.
Set throttle lever from medium speed to high
speed, and pull starter handle until engine
starts.
Once engine starts, cutting tool
starts rotating. Pay full attention to cutting
tool.
If engine will not start still, remove spark plug,
dry the electrode, and reassemble them as
they originally are. Then, start as specified.
Detached plug cap. Attach securely.
Contaminated spark plug. Clean.
Abnormal clearance of spark plug. Adjust clearance.
Other abnormality of spark plug. Replace.
Abnormal carburetor. Make request for inspection and maintenance.
Starter rope cannot be pulled. Make request for inspection and maintenance.
Abnormal drive system. Make request for inspection and maintenance.
Engine stops soon.
Engine speed does not increase.
Insufficient warm-up. Perform warm-up operation.
Choke lever is set to “CLOSE” although
engine is warmed up.
Set to “OPEN”.
Clogged fuel filter. Clean.
Contaminated or clogged air cleaner. Clean.
Abnormal carburetor. Make request for inspection and maintenance.
Abnormal drive system. Make request for inspection and maintenance.
Metal blade does not rotate.
Stop engine immediately.
Loosened metal blade-tightening nut. Tighten securely.
Twigs caught by metal blade or dispersion-
preventing cover.
Remove foreign matter.
Abnormal drive system. Make request for inspection and maintenance.
Main unit vibrates abnormally.
Stop engine immediately.
Broken, bent or worn metal blade. Replace metal blade.
Loosened metal blade-tightening nut. Tighten securely.
Shifted convex part of metal blade and metal
blade support fitting.
Attach securely.
Abnormal drive system. Make request for inspection and maintenance.
Metal blade does not stop immediately.
Stop engine immediately.
High idling rotation. Adjust.
Detached throttle wire. Attach securely.
Abnormal drive system. Make request for inspection and maintenance.
Engine does not stop.
Run engine at idling, and set choke lever
to “CLOSE”.
Detached connector. Attach securely.
Abnormal electric system. Make request for inspection and maintenance.