Download Arrow VM1012-B Specifications

ENGINE
XJ
9-9
DIAGNOSIS AND TESTING (Continued)
SERVICE DIAGNOSIS—DIESEL—MECHANICAL.
CONDITION
POSSIBLE CAUSES
CORRECTION
LUBRICATING OIL
PRESSURE LOW
1. Low oil level.
1. (A) Check and fill with clean engine
oil.
(B) Check for a severe external oil leak
that could reduce the pressure.
LUBRICATING OIL
PRESSURE TOO HIGH
2. Oil viscosity thin, diluted or wrong
specification.
2. Verify the correct oil is being used.
Check for oil dilution. Refer to
Contaminated Lube Oil (Engine
Diagnosis Mechanical).
3. Improperly operating pressure
switch/gauge.
3. Verify the pressure switch is
functioning correctly. If not, replace
switch/gauge.
4. Relief valve stuck open.
4. Check/replace valve.
5. Plugged oil filter.
5. Change oil filter. Oil filter change
interval may need to be revised.
6. If cooler was replaced, shipping
plugs left in cooler.
6. Check/remove shipping plugs.
7. Worn oil pump.
7. Check and replace oil pump.
8. Suction tube loose or seal leaking.
8. Check and replace seal.
9. Loose main bearing cap.
Check and install new bearing and
tighten cap to proper torque.
10. Worn bearings or wrong bearings
installed.
10. Inspect and replace connecting rod
or main bearings. Check and replace
piston cooling nozzles.
11. Oil jet under piston bad fit into
main carrier.
11. Check oil jet position.
1. Pressure switch/gauge not operating
properly.
1. Verify the pressure switch is
functioning correctly. If not, replace
switch/gauge.
2. Engine running to cold.
2. Refer to Coolant Temperature Below
Normal (Engine Diagnosis
Performance).
3. Oil viscosity too thick.
3. Make sure the correct oil is being
used, (Refer to Group 0, Lubrication
and Maintenance).
4. Oil pressure relief valve stuck
closed or binding.
4. Check and replace valve.