ISM, ISMe, and QSM11 – Engine Noise Excessive — Connecting Rod

Symptom Tree  t049

This is symptom tree t049
Cause Correction

Refer to Engine Noise Diagnostic Procedures — General Information at the end of this section before using this symptom tree.

Lubricating oil pressure is below specification

Check the oil pressure. Refer to Procedure 007-028. If the pressure is low, refer to the Lubricating Oil Pressure Low symptom tree.

 

Lubricating oil level is below specification

Check the oil level. Verify the dipstick calibration and the oil pan capacity. Fill the system to the specified level. Refer to Procedures 007-009 and 007-025.

 

Lubricating oil is thin or diluted

Refer to Procedure 007-999, Lubricating Oil System – Overview in Section F. If the oil pressure is low, refer to the Lubricating Oil Pressure Low symptom tree.

 

Connecting rod capscrews are loose or not tightened correctly

Check the torque on the connecting rod capscrews. Refer to Procedure 001-014.

 

Connecting rod and bearings are damaged or worn, are not assembled correctly, or are the wrong bearings

Inspect the connecting rod and bearings. Refer to Procedure 001-005.

 

Connecting rod is bent or out of alignment

Remove and inspect the connecting rods. Refer to Procedure 001-014.

 

Crankshaft journals are damaged or out of round

Inspect the crankshaft journals. Refer to Procedure 001-016.

 
Last Modified:  13-Oct-2005