Hi Me again..
So stripped the head and barrels off, camshaft and followers look OK, head needs some work but that will be another story. I am a bit confused by my Haynes manual regarding piston to barrel clearance. My manual says to put the piston without rings down into the barrel 3/4inch from top and see if its possible to insert a 0.005 feeler guage between the two - I can a 0.009 is a sliding fit - the wierd thing is I have the same gap all around the piston not just on the thrust side - I can't measure much difference between the thrust and non thrust sides. I have the same gap at the top and bottom of the bore - I cant feel any ridge between where the piston slides and the virgin part of the bore. I can see a line a slightly different colour but there doesn't seem to be any wear. Is my manual leading me the wrong way? Piston skirts have slight scuff marks on both sides about 3/4 inch wide.
Cheers
John