Reasons for Low Engine Oil Pressure

TM 9-2320-312-24-2

Testing and Adjusting Section

6. Compare the recorded engine oil pressure with

2. Start the engine. Run the engine with SAE

the oil pressure indicators on the instrument

10W30 or SAE 15W40 oil. The information in the

panel and the engine oil pressure that is

engine oil pressure graph is invalid for other oil

displayed on the electronic service tool.

viscosities. Refer to Operation and Maintenance

Manual, "Engine Oil" for the recommendations

7. An engine oil pressure indicator that has a

of engine oil.

defect or an engine oil pressure sensor that

has a defect can give a false indication of a

Note: Allow the engine to reach operating

low oil pressure or a high oil pressure. If there

temperature before you perform the pressure test.

is a notable difference between the engine oil

pressure readings make necessary repairs.

Note: The engine oil temperature should not exceed

115 C (239 F).

8. If low engine oil pressure is determined, refer to

"Reasons for Low Engine Oil Pressure".

3. Record the value of the engine oil pressure when

the engine has reached operating temperature.

9. If high engine oil pressure is determined, refer to

"Reason for High Engine Oil Pressure".

4. Locate the point that intersects the lines for

the engine rpm and for the oil pressure on the

engine oil pressure graph.

Reasons for Low Engine Oil

Pressure

NOTICE

Keep all parts clean from contaminants.

Contaminants may cause rapid wear and shortened

component life.

NOTICE

Care must be taken to ensure that fluids are contained

during performance of inspection, maintenance, test-

ing, adjusting and repair of the product. Be prepared to

collect the fluid with suitable containers before open-

ing any compartment or disassembling any compo-

nent containing fluids.

Refer to Special Publication, NENG2500, "Caterpillar

Tools and Shop Products Guide" for tools and supplies

suitable to collect and contain fluids on Caterpillar

products.

g00866125

Illustration 67

Engine Oil Pressure Graph

Dispose of all fluids according to local regulations and

mandates.

5. The results must fall within the "ACCEPTABLE"

range on the chart. A problem exists when the

Engine oil level is low. Refer to Step 1.

results fall within the "NOT ACCEPTABLE" range

on the chart. The problem needs to be corrected.

Engine oil is contaminated. Refer to Step 2.

Engine failure or a reduction in engine life can

be the result if engine operation is continued with

The engine oil bypass valves are open. Refer to

oil manifold pressure outside this range.

Step 3.

Note: A record of engine oil pressure can be used

The engine lubrication system is open. Refer to

as an indication of possible engine problems or

Step 4.

damage. A possible problem could exist if the

oil pressure suddenly increases or decreases

The oil suction tube has a leak or a restricted inlet

70 kPa (10 psi) and the oil pressure is in the

screen. Refer to Step 5.

"ACCEPTABLE" range. The engine should be

inspected and the problem should be corrected.

The engine oil pump is faulty. Refer to Step 6.

Engine Bearings have excessive clearance. Refer

to Step 7.