Piper Navajo PA-31 Service Manual page 520

PIPER NAVAJO SERVICE MANUAL
TABLE VIII-II.
Trouble
Rough engine.
Low oil pressure.
TROUBLESHOOTING CHART (ENGINE) (cont.)
Cause
Remedy
Cracked engine mount.
Repair or replace mount.
Defective mounting bushings.
Install new mounting bushings.
Uneven compression.
Check compression.
Blocked fuel nozzles.
Clean per paragraph 8-49.
Insufficient oil.
Fill sump with recommended
oil.
Air lock or dirt in relief
valve.
Leak in suction line or
pressure line.
Dirty oil strainers.
High oil temperature.
Defective pressure gauge.
Stoppage in oil pump intake
passage.
Oil pressure relief seat
damaged or cocked.
Pressure relief out of
adjustment.
Inadvertant relocation of oil
pressure takeoff point on
engine.
Oil pressure improperly
adjusted.
Improper weight of oil.
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 gauge.
Check line for obstruction.
Clean suction strainer.
Remove, and replace or repair.
Adjust to proper limits.
Use only the oil pressure take-
off point approved by the
manufacturer.
Adjust.
See latest revision of S.I. 1014
for correct oil.
Remove blockage from oil
passage.
POWER PLANT
High oil pressure.
Oil passage from pressure relief
valve to sump plugged.
Revised: 9/24/81
2J22