Toro Lawn-boy - Engine Smokes Excessively (Smoke is light colored, engine runs well); Engine Smokes Excessively (Smoke is dark, engine runs poorly)

TROUBLESHOOTING
10
Engine Pre-Ignites
Engine Smokes Excessively (Smoke is light colored, engine runs well)
Engine Smokes Excessively (Smoke is dark, engine runs poorly)
Possible Causes Remedies
Wron
g
spark plu
g
- too hot Install the correct type of spark plu
g
Low quality fuel (old or stale) Replace with fresh, unleaded re
g
ular fuel
Carbon buildup in en
g
ine Decarbon en
g
ine and muffler
Excessive alcohol in fuel Replace with fresh unleaded fuel havin
g
no more than
10% ethanol
Sheared flywheel key Inspect and repair
Possible Causes Remedies
Sli
g
ht oil accumulation in crankcase None; normal on start-up
Air cleaner element clo
gg
ed Clean and re-oil or replace air cleaner element, mower
only
Fuel/oil mixture too rich Drain fuel tank and fill with fuel of correct mixture
Choke is in “On” position Move to hi
g
h speed or “Off” position
Possible Causes Remedies
Carburetor runnin
g
too rich Clean and check carburetor
Choke is in “On” position Move to hi
g
h speed or “Off” position