**Causes:**  

A) Incorrect lubricating oil level  

B) Faulty lubricating oil pressure gauge  

C) Lubricating oil diluted by fuel  

D) Incorrect lubricating oil specification  

E) Lubricating oil temperature exceeds normal value (120°C)  

F) Dirty lubricating oil filter  

G) Worn or damaged crankshaft bearings  

H) Worn lubricating oil pump  

I) Pressure relief valve failing to close  

J) Damaged pressure relief valve  

K) Fault in lubricating oil pump suction pipe  

L) Blocked oil pan suction filter  

**Remedial Measures:**  

A) Check for lubricating oil leaks. Add or drain lubricating oil as required.  

B) Check the markings on the oil dipstick  

C) Inspect the lubricating oil pressure gauge  

D) Replace the lubricating oil. If oil becomes diluted again, contact an authorized repair service  

E) Replace the lubricating oil and verify the oil specification  

F) Inspect, clean, or replace the lubricating oil cooler  

G) Replace the lubricating oil filter  

H) Inspect/replace the crankshaft bearings  

I) Inspect, repair/replace the lubricating oil pump  

J) Replace the pressure relief valve  

K) Replace the pressure relief valve  

L) Inspect, repair/replace the suction pipe and clean the suction filter