Knocks at Idle Hot

- Loose or worn drive belts. Adjust tension and/or replace as necessary.
- A/C compressor (if equipped or generator bearing. Replace as necessary.
- Valve train. Replace parts as necessary.
- Improper oil viscosity. Install proper viscosity oil for expected temperature. Refer to Maintenance and Lubrication for engine oil specifications.
- Excessive piston pin clearance. Replace piston and pin.
- Connecting rod alignment. Check and replace rods as necessary.
- Loose crankshaft balancer. Torque and/or replace worn parts.
- Piston pin offset to wrong side. Install correct piston.