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Roger Moss

It is a preferred option when I rebuild engines to substitute the hard screwed rings on the back of the crank that form the rear retaining wall to the main bearing rollers with a bronze ring that performs the same duty. The back side of this ring acts to control end float of the crank assembly and so does away with spring loaded hard metal to metal face glands which are intolerant of oil starvation and alignment inaccuracies, if the flywheel tapers have bee compromised as many have.
I fit a bronze insert in the cup centre bore which is a housing for a synthetic seal. The whole system is completed with a non return valve under each oil feed elbow on the inner top of the case. If you have oil leaks then either your gland is not seating due to taper axis errors in the flywheel, or more likely the old problem of the crankcase metal expanding when hot and providing a small gap between the cup and the cup bore at the inside rear of the cup, where the oil hole is very near the inner edge. Scotts tried to allieviate this by spinning a groove but it was not successful. A modern cure is a thorough degrease and apply a good wiped bead of RTV silicone to fill the corner betwwen cup and case. This will expand and contract with temperature variations. Try this first as the system I use is really part of a rebuild. Roger Moss