DIAGNOSIS AND TESTING - ENGINE DIAGNOSIS - MECHANICAL
| CONDITION |
POSSIBLE CAUSES |
CORRECTIONS |
| NOISY VALVES |
1. High or low oil level in crankcase. |
1.
(Refer to LUBRICATION & MAINTENANCE - SPECIFICATIONS) |
| 2. Thin or diluted oil. |
2. Change oil and filter. |
|
| 3. Low oil pressure. |
3. Check oil pump, if Ok, check rod and main bearings for excessive wear. |
|
| 4. Dirt in lash adjusters. |
4. Replace as necessary. |
|
| 5. Worn rocker arms. |
5. Replace as necessary. |
|
| 6. Worn lash adjusters |
6. Replace as necessary. |
|
| 7. Worn valve guides. |
7.
(Refer to 9 - ENGINE/CYLINDER HEAD/INTAKE/EXHAUST VALVES & SEATS - STANDARD PROCEDURE) |
|
| 8.
Excessive runout of valve seats on valve faces. |
8.
(Refer to 9 - ENGINE/CYLINDER HEAD/INTAKE/EXHAUST
VALVES & SEATS - STANDARD PROCEDURE) |
|
| CONNECTING ROD NOISE |
1. Insufficient oil supply. |
1.
(Refer to LUBRICATION & MAINTENANCE - SPECIFICATIONS) |
| 2. Low oil pressure. |
2. Check oil pump, if Ok, check rod and main bearings for excessive
wear. |
|
| 3. Thin or diluted oil. |
3. Change oil and filter. |
|
| 4. Excessive bearing clearance. |
4. Replace as necessary. |
|
| 5. Connecting rod journal out-of-round. |
5. Service or replace crankshaft. |
|
| 6. Misaligned connecting rods. |
6. Replace bent connecting rods. |
|
| MAIN BEARING
NOISE |
1. Insufficient oil supply. |
1.
(Refer
to LUBRICATION & MAINTENANCE - SPECIFICATIONS) |
| 2. Low oil pressure. |
2. Check oil
pump, if Ok, check rod and main bearings for excessive wear. |
|
| 3. Thin or diluted oil. |
3. Change oil and filter. |
|
| 4. Excessive bearing clearance. |
4. Replace as necessary. |
|
| 5. Excessive end play. |
5. Check thrust washers for wear. |
|
| 6. Crankshaft journal out-of round. |
6. Service or replace crankshaft. |
|
| 7. Loose flywheel or torque converter. |
7. Tighten to correct torque |