Originally posted by Drew, II # 4211:
I'm curious: Did removing the plug wire thereby omit the plug firing and reduce the piston pressure thus lessening the force on the wrist pin bushing? And then the sound lessened?
Yes. I had the engine running, pulled the plug wires one at a time. When I found the cylinder that seemed different with the plug off, I set the plug wire on, and then off, repeated until I was sure I'd found the noise. Plug on=bad noise, plug off=no noise.
Since I had already pulled the pan and measured and inspected the bearings with plastiguage, I knew it had to be in the piston.
I was fortunate that the wrist pin and piston were fine. I was worried that the pin had "walked" to one side, and was chewing into the cylinder wall. Since the only thing wrong was the bushing, I had it replaced and back on the road without too much trouble.
