
RENR9968-02 43
Testing and Adjusting Section
2. Start the engine. Run the engine with SAE 10W30
or SAE 15W40 oil. The information in the engine
oil pressure graph is invalid for other oil viscosities.
Refer to Operation and Maintenance Manual for
the recommendations of engine oil.
Note: Allow the engine to reach operating
temperature before you perform the pressure test.
Note: The engine oil temperature should not exceed
115°C(239°F).
3. Record the value of the engine oil pressure when
the engine has reached operating temperature.
4. Locate the point that intersects the lines for the
engine rpm and for the oil pressure on the engine
oil pressure graph.
g01046794
Illustration 36
5. The res
ults mu st fall with in the “ACCEPTAB LE”
range on the chart. A problem exists when the
results fall within the “NOT ACCEPTABLE” range
on the
chart. The problem needs to be corrected.
Engine failure or a reduction in engine life can be
the result if engine operation is continued with oil
manif
old pressure outside this range.
Note: A record of engine oil pressure can be used as
an indication of possible engine problems or damage.
A possible problem could exist if the oil pressure
suddenly increases or decreases 70 kPa (10 psi) and
the oil pressure is in the “ACCEPTABLE” range. The
engine should be inspected and the problem should
be corrected.
6. Compare the recorded engine oil pressure with
the oil pressure indicators on the instrument panel
and the engine oil pressure that is displayed on
Cat ET.
7. An engine oil pressure indicator that has a defect
or an engine oil pressure sensor that has a defect
can give a false indication of a low oil pressure or
a hig h oil pressure. If t he re is a n otable difference
between the engine o il pressure readings make
necessary repairs.
8. Refer to “Reasons for Low Engine Oil Pressure” if
you determine that the engine oil pressure is low.
9. Refer to “Reasons for High Engine Oil Pressure” if
you determine that the engine oil pressure is high.
Reasons for Low Engine Oil
Pressure
NOTICE
Keep all parts clean from contaminants.
Contaminants may cause rapid wear and shortened
component life.
NOTICE
Caremustbetakentoensurethatfl uids 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 Pu blication, NENG2500, “Caterpilla r
Dealer Service Tool Catalog” for tools and supplies
suitable to co llect and contain flu ids on Caterpillar
products.
Dispose of all fluids according to local regulations and
mandates.
•
Engine oil level is low. Refer to Step 1.
•
Engine oil is contaminated. Refer to Step 2.
•
The engine oil bypass valves are open. Refer to
Step 3.
•
The engine lubrication system is open. Refer to
Step 4.