| • | 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 grounded out. Cold engine piston knock which disappears in 1.5 minutes should be considered acceptable. | 
| • | Bent connecting rod. |