I've got a 76 motorhome 440 with a seriously seized ring. The guy I bought it from says mice pissed in the cylinder but I'm pretty sure thats not possible considering the amount of rust I had to bore off the cylinder wall. Either way the top piston ring on cylinder 1 is rusted to the piston and after soaking it in oil for a week and trying to knock it loose with a hammer I'm pretty sure there's no way I'm freeing it in one piece. I'm looking for a single replacement piston ring but can't seem to find one. I was also wondering if replacing just one piston ring is advisable or if I need to do the whole piston or all 8. Thanks.
