Save The Piston, Remove The Pins
Before removing press-fit pistons that we plan on reusing, we immerse the piston in a coffee can of motor oil. You only need enough oil to submerge the piston. We use synthetic oil for the EP and high temperature qualities. We then heat it to about 250 degrees. This expands the piston away from the pin to minimize scratching of the pin bore and lubricates the pin in its travel through the rod end. Our hotplate is an industrial type with a thermostat, so we set the temp and don’t have to worry about overheating the oil and having it burst into flames. By using this method, we seldom have to pin hone the pistons, and have never distorted one, but polishing the pins is still re- quired. Many of the engines that need to be balanced use inexpensive pistons with broached slots in the pin bores, which makes pin honing difficult.

Timm Jurincie
Tuff-Enuf Auto & Marine Performance
Avondale, AZ
November, 2015