Getting fed up now!!

[hendy]

You are putting the seal in correctly? Spring side to crank web.

Well I think so, but I'm questioning everything in my head now.

I will rig up a leak test though next time

+1

I couldn't believe how many leaks I found on my current build despite being fastidious about fitting seals and gaskets well. If your castings have damage, even if it's minor then you can get a leak.

[bazza3004]

Sorry if you have already answered this but are you using the original crank ? Only ask as i rebuilt a resto scoot for a mate and used the original crank as bigend was fine. This smoked like a mill chimney and after stripping crank out again found wear marks where the drive side seal runs, swapped cranks and all was good .

[jonashford]

have u tried a different seal plate like a MB or AF stainless remade one?

[Ilango]

Start the engine. At idle drain the oil from chain cover. As the oil gets emptied the idle speed tends to increase, which indicates a problem with drive side seal.
Could be due to the seal placed wrongly or lose bolts on the seal retainer plate.
Any which ways it is not going to self heal. The engine has to be opened up again.
While installing the crank apply a thing film of grease on the crank interface with the seal. While pulling the crank towards the drive side, slowly rotate the crank as the crank is being pulled. This way any folding on the seal lip could be avoided.
Hope this helps.

[Shipleystevep]

Last play today, checked breather all ok. Drained oil smoking stopped.
Looks like strip and re-build. I used Viton seals so will try Rolf
Just ordered bits to make a leak test kit, will test before I strip it then see what I can find.
Thanks very much all for your inputs, much appreciated
Cheers
Steve

[roadrunnerian]

I put Viton oil seals in a t5 vespa engine took them out straight away they leaked straight away