Knocks Cold and Continues For 2 to 3 Minutes

- Engine flywheel contacting the splash shield. Reposition the splash shield.
- Loose or broken crankshaft balancer or drive pulleys. Tighten or replace as necessary.
- Excessive piston to bore clearance. Replace the piston.
- Cold engine knock usually disappears when the specific cylinder secondary ignition circuit is 9 rounded out. Cold engine piston knock which disappears in 1.5 minutes should be considered acceptable.
- Bent connecting rod.