Probable Causes
Vibration Damper
- Inspect the vibration damper.
Engine Mounts and Brackets
- Engine supports
- Driven equipment
Engine Misfiring or Running Rough
- Engine misfiring
- Running rough
Recommended Actions
Inspect the Vibration Damper
Check the vibration damper for damage. Install a new vibration damper, if necessary. Inspect the mounting bolts for damage and/or for wear. Replace any damaged bolts. Refer to the Disassembly and Assembly manual.
Engine Supports
Inspect the mounts and the brackets while you run the engine through the speed range. Look for mounts and brackets that are loose and/or broken. Tighten all of the mounting bolts. If necessary, replace any damaged components. Check the alignment of the following before operating the engine under load for any length of time:
- Mounts
- Coupling
- Crankshaft deflection
Driven Equipment
Inspect the mounting bolts for the driven equipment. Inspect the alignment and the balance of the driven equipment. Inspect the coupling. If necessary, disconnect the driven equipment and test the engine.
Engine Misfiring or Running Rough
Refer to Troubleshooting, “Engine Misfires, Runs Rough or Is Unstable”.