mystery oil leak

[jerry]

I have posted about this before , 750ss has a mystery oil leak on the rear cylinder , i have removed it and replaced all gaskets and O rings and it also has a new breather assembly

still leaks on rear left hand corner and about 1/2 way up the cylinder? compression is OK so cylinder can be craked ,, now i am at a complete loss of ideas ????

[Nickj]

Just a random guess.. it's not oil seeping up between the liner, probably not but seen it on big overbores where a new sleeves been machined in OR from the oilway?

[FRASER24]

I think I can help you with that one , I had identical problem with an old 900ss, it is oil getting past the base gasket and making its way up alongside one of the barrel /head studs, to where the head joins the barrel, it then leaks out and runs out over the barrel fins. It was most noticable after a sustained high speed run, but wouldn't leak on tickover. After 2 attempts to fix it, I applied thread sealant to all barrel studs where they locate into the crankcase, I then used the recommened sealant on base gasket ( it seems almost identical to impact adhesive) put it all back together and no more leaks. I believe that crankcase pressure was contributing to push the oil up the barrel. hope this helps, Fraser

[jerry]

Thanks fraser i will look in to that solution ,,, sound very plausible i will use WELLSEAL