CONDITION | POSSIBLE CAUSES | CORRECTIONS |
NOISY VALVES | 1. High or low oil level in
crankcase. 2. Thin or diluted oil. 3. Low oil pressure. 4. Dirt in lash adjusters. 5. Bent push rods. 6. Worn rocker arms. 7. Worn tappets 8. Worn valve guides. 9. Excessive runout of valve seats on valve faces. |
1. Refer to Group 0, Lubrication and
Maintenance. 2. Change oil and filter. 3. Check oil pump, if Ok, check rod and main bearings for excessive wear. 4. Clean lash adjusters. 5. Replace as necessary. 6. Replace as necessary. 7. Replace as necessary. 8. Refer to Valve Service in this section. 9. Service valves and valve seats. Refer to Valve Service in this section. |
CONNECTING ROD NOISE | 1. Insufficient oil supply. 2. Low oil pressure. 3. Thin or diluted oil. 4. Excessive bearing clearance. 5. Connecting rod journal out-of-round. 6. Misaligned connecting rods. |
1. Refer to Group 0, Lubrication and
maintenance. 2. Refer to Group 0, Lubrication and maintenance. 3. Change oil and filter. 4. Replace as necessary. 5. Service or replace crankshaft. 6. Replace bent connecting rods. |
MAIN BEARING NOISE | 1. Insufficient oil supply. 2. Low oil pressure 3. Thin or diluted oil. 4. Excessive bearing clearance. 5. Excessive end play. 6. Crankshaft journal out-of round. 7. Loose flywheel or torque converter. |
1. Refer to Group 0, Lubrication and
maintenance. 2. Refer to Group 0, Lubrication and maintenance. 3. Change oil and filter. 4. Replace as necessary. 5. Check No. 3 main bearing for wear on flanges. 6. Service or replace crankshaft. 7. Tighten to correct torque |