ISC, ISCe, QSC8.3, ISL, ISLe3, ISLe4 and QSL9 Engines – 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 Section TS before using this 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 007-037 and 007-009.


Lubricating oil pressure is below specification

Check the oil pressure. If the pressure is low, refer to Procedure 007-037.


Lubricating oil is thin or diluted

Refer to Procedure 007-083. If the oil pressure is low, refer to the Lubricating Oil Pressure Low symptom tree.


Block stiffener plate is misassembled

Remove and inspect block stiffener plate. Refer to Procedure 001-089.


Lubricating oil suction or transfer tube misassembled

Remove and inspect the lubricating oil suction or transfer tube. Refer to Procedure 007-035.


Crankshaft journals are damaged or out of round

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


Connecting rod capscrews are loose or not tightened correctly

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


Connecting rod is bent or out of alignment

Remove and inspect the connecting rods. 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 001-014.

Last Modified:  29-Jul-2005