Service Manual

TROUBLESHOOTING
8
Engine Lacks Power
Engine Surges
Engine Backfires
Possible Causes Remedies
Dull blade Sharpen or replace blade, mower only
Housin
g
choked with
g
rass and debris Clean housin
g
thorou
g
hly, mower only
Plu
gg
ed exhaust system Clean exhaust ports
Muffler plu
gg
ed Clean or replace muffler
Flywheel key sheared Replace flywheel key
Carburetor dirty Clean carburetor
Intake air leak Repair or replace failed components(s)
Low compression See “En
g
ine Has Low Compression” table
Possible Causes Remedies
Fouled idle circuit Clean idle circuit
Air leak Check sealin
g
surfaces, oil seals,
g
askets, and port plu
g
s
Restricted fuel flow Check filters and fuel line
En
g
ine RPM low Adjust to proper specification. Note: A sli
g
ht sur
g
e at no
load is normal.
Governor link misadjusted (R tek) Adjust
Air vane stickin
g
Clean or replace
Possible Causes Remedies
Flywheel key sheared Replace key
Muffler filled with carbon Clean muffler
Exhaust ports plu
gg
ed Clean ports
Air leak to crankcase Replace seals or re-seal crankcase to cylinder
Spark plu
g
partly fouled Clean or replace