OutdoorKing Repair Forum Forums General Discussion Forum Off Topics Stuck Piston - Rudge Motor

My brother rang from Sydney today with a problem with a stuck piston in a 1937 Rudge motor. Everything is rusted up as well as the crank. In trying to get it apart so far in the pics I noticed a fin has been broken off in 3 pieces. Now I have welded small broken fins off before, but I have only put small welds on them to prevent any heat distortion. I'm wondering if after tacking the fin pieces into position with small welds, does anybody know if something like JB Weld could be used to fill in between the welds and would it be able to handle the heat. The barrel is cast iron and if it is ever running again I would only expect it be run for display or short club events

If it's cast iron the best thing is to use oxy acetylene or oxy lpg and braze it. Clean thoroughly and preheat the parts and use a good flux and brass rod. Some high temp paint afterwards and no one will ever know.

+1 to aussietrev here. Don't know of any type of glue that would take the temperatures that cylinder fins can reach.

I have suggested that they soak the barrel/piston in ATF/Acetone mix for a few weeks, (suits the owner because he works offshore) and hopefully when he gets back they may be able to free the piston up

I used ATF & thinners for three weeks on a Villiers Midget that was seized up with no success so the threw the whole thing into a bucket of diesel for a further three and a bit weeks. I was suprised to find that it was free enough to turn and get the piston out at the end of this soaking. Don't know if it was one or the other or a combination of both that did the trick but that motor is now running on my Ransomes Minor Mk 7 so be prepared to try everything if one doesn't work.