Centinel System – Repair Manual – Engine Noise Excessive — Main Bearing

Interview the operator to verify the complaint

Refer to Driveability-General Information, the Driveability/Low-Power Customer Complaint Form, and the Driveability Checklist at the end of Section TS. Follow the instructions on the forms before continuing with this tree.

Electronic fault codes active or high counts of inactive fault codes

Refer to Section TF Section TF in the Troubleshooting and Repair Manual, CM870 Electronic Control System, Signature and ISX Engines, Bulletin 4021334, or the Troubleshooting and Repair Manual Electronic Control System Signature ISX and QSX15 Engines, Bulletin 3666259, or the Troubleshooting and Repair Manual, Power Generation Control Systems QSX15, QSK23, QSK45, QSK60, QSK78, and QST30 Series Engines, Bulletin 4021419 for fault code troubleshooting.

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 Procedure 007-009 and 007-037.

Lubricating oil pressure is below specification

Check the oil pressure. If the pressure is low, refer to Procedure 007-028.

Flywheel is loose or damaged

Check the flywheel. Refer to Procedure 016-005.

Torque converter is loose

Check the torque converter. Refer to the OEM service manual.

Main bearing capscrews are loose, worn or not tightened correctly

Check the torque on the main bearing capscrews. Inspect the capscrews for wear. Refer to Procedure 001-006.

Main bearings are damaged or worn, or the wrong bearings are installed

Inspect the main bearings for damage, excessive wear, and the correct part number. Refer to Procedure 001-006.

Thrust bearings are damaged

Inspect the thrust bearing for damage. Refer to Procedure 001-007.

Internal engine damage

Analyze the oil and inspect the filters to locate an area of probable damage. Refer to Procedure 007-013.