Rough Engine; Low Oil Pressure; High Oil Temperature - Lycoming O-290 Operator's Manual

LYCOMING OPERATOR'S MANUAL
O-235 AND O-290 SERIES
TROUBLE

Rough Engine

Low Oil Pressure

High Oil Temperature

PROBABLE CAUSE
Cracked engine mount.
Unbalanced propeller.
Defective mounting bushings.
Malfunctioning engine.
Insufficient oil.
Air lock or dirt in relief valve.
Leak in suction line or pressure
line.
Dirty oil strainers.
High oil temperature.
Defective pressure gage.
Stoppage – oil pump intake
passage.
Insufficient air cooling.
Insufficient oil supply.
Low grade of oil.
Clogged oil lines or strainers.
Excessive blow-by.
Failing or failed bearing.
Defective temperature gage.
TROUBLE-SHOOTING
REMEDY
Replace mount.
Remove propeller and have it
checked for balance.
Install new mounting bushings.
Check entire engine.
Fill sump to proper level with oil
of recommended grade.
Remove and clean oil pressure
relief valve.
Check gasket between accessory
housing and crankcase.
Remove and clean oil strainers.
See "High Oil Temperature" in
"Trouble" column.
Replace gage.
Check line for obstruction. Clean
suction strainer.
Check air inlet and outlet for
deformation or obstruction.
Fill oil sump to proper level with
oil of recommended grade.
Replace with oil conforming to
specification.
Remove and clean oil strainers.
Usually caused by worn or stuck
rings. Complete overhaul
required.
Examine sump for metal particles.
If found, complete overhaul of
engine is indicated.
Replace gage.
SECTION 6
6-3