I've this old piston that I hope has a bit of remaining life - if I can only replace the rings! The problem is getting the old ones out. It was running on Castrol R and the top two rings are well and truly stuck; I can't get even a dentist's tooth pick in at the ring gap (probably lack of gap was the problem). Are there solvents for Castrol R? Can you use a small cutting disc to dismember the ring?
Any advice will be very much appreciated, MikeN.