I'm sure this must have been mentioned before, so apologies if I have forgotten previously published solutions.
Last weekend I managed to remove the piston that has been long seized into the cylinder of the Lister CS 5/1 that I rescued a couple of years ago. The rings are solid with carbon and can't even see the gaps at present.
What's the best way to get rid of the carbon so that the condition of the rings can be assessed?
I saw a letter in Model Engineer recently concerning removal of carbon from inside the vapouriser coil of old paraffin bowlamps - heat to red and blow oxygen through to convert the solid carbon to CO2 - would this work for a piston, or is there too much risk of damage?