MTD 521 Operator's Manual page 11

Troubleshooting Guide
Problem
PossibleCause(s)
CorrectiveAction
Engine fails to start
Dirty air cleaner
Engineneedsto be primed
Fueltank empty
Stalefuel in gasolinetank
Spark plug wiredisconnected.
Spark plugfouled
Engineflooded
Referto the EngineManualpackedwithyour unit.
Pushprimerbulb two or threetimes.
Filltank withclean,fresh gasoline.
Draingasolineand refilltank withclean,freshgasoline.
Connectthe spark plug wire to the spark plug.
Clean,adjust gapor replacespark plug.
Referto the EngineManualpackedwithyour unit.
Engine runs erratic
Spark plug wire loose
Stalefuel in gasolinetank
Ventin gas cap plugged
Wateror dirt infuel system
Dirty air cleaner
Carburetorout of adjustment
Connectand tighten sparkplug wire.
Draingasoline& refilltank with clean,fresh gasoline.
Clear vent of anydebris.
Drainfuel tank. Refillwith fresh fuel.
Referto the EngineManualpackedwith yourunit.
Referto the EngineManualpackedwith yourunit.
Engine Overheats
Engineoil levellow Fillcrankcasewith properoil.
Air flowrestricted Clean the area aroundthe engine'scoolingfins.
Dirty air filter Replacethe engine'sair filter.
Carburetornot adjustedproperly Referto the EngineManualpackedwith yourunit.
ExcessiveVibration
Edgerbladebent or damaged Replaceedgerblade.
Bladespindlebentor damaged Contactan authorizedMTDservicedealer.
Drivebelt Slips
Belt wornor stretched Replacedrivebelt.
11
eshooting
Guide
Forparts and/or
accessories please
carl 1-330-220-468&
or 1-800-800-7310
www.mtdproducts.com