Hole in piston

[Colin Cheesman]

My gut feeling is that the top of the piston has been over skimmed probably in an attempt to correct the deck height after skimming the block, this has left the crown of the piston too thin causing it to overheat and hole. I can not see evidence of it running excessively weak, if it were that and or timing issues I would expect all other cylinders to be effected, it will be most interesting to see further pictures once you have it apart. If I am correct a hone and new pistons should cure, BUT i would place a shim under the block rather than skim excessive metal off the pistons.
Keep us posted please.

Thanks Ian, what you say makes complete sense, hopefully should have the engine apart by the end of the week and will report back, our club has shims available so should be able to fix.

Colin