Main Bearing Noise

MAIN BEARING NOISE

Possible Causes
1. Insufficient oil supply.
2. Low oil pressure.
3. Thin or diluted oil.
4. Excessive 6earing clearance.
5. Excessive end play.
6. Crankshaft journal out-of-round, worn.
7. Loose flywheel or torque converter.

Correction
1. Check engine oil level.
2. Check engine oil level. Inspect oil pump relief valve and spring.
3. Change oil to correct viscosity.
4. Measure hearings for correct clearance.Repair as necessary.
5. Check thrust hearing for wear on flanges.
6. Grind journals or replace crankshaft.
7. Tighten to correct torque.