Before 6 months I dismantled the crankcases for a complete rebuild. Though I took utmost care to put them back together, I can see oil leaking between the crankcases. Not much but enough to keep me worrying. Is there any remedy for this as I do not want to separate the cases again. Please let me know if you have any advice for me.
Re: 1941 Matchless G3L - Oil Leak Between Crankcases
Very sorry to here that Pratap, after all your efforts. The original sealant was probably Shellac. Nowadays we are spoilt for choice.....Wellseal, Loctite and many others. I'm afraid I can't see any way to seal it if you can't live with it, other than strip the engine again. Ron
Re: 1941 Matchless G3L - Oil Leak Between Crankcases
Thes engines do not normally leak from this area, matchless crankcase were machined in pairs to high finish.
If it leaks then no amount of discussing fancy sealants will solve anything.
Bite the bullet and take it apart,find the cause before anything else.
Wellseal is about as near to the original shellac based sealant as you can get, but Gold size available in any artist supply shop is what used to be used in the 1920, and as good, but a sod to part later.
At risk of starting off yet another argument about it, stay away from silicone sealant in the crankcase joints.
Or alternative, degrease throughly and paint over it all with WD green paint, as the army did!!:scream:
Re: 1941 Matchless G3L - Oil Leak Between Crankcases
Agree with everything Ken said. Norton 16h's were also assembled with Gold Size, (its actually mentioned in the maintenance manual). One of the reasons I bought mine was that the engine rebuilder had also used it. It was only used on the crankcase joint as far as I know with greased paper gaskets on the others, ie barrel to crankcase.
Re: 1941 Matchless G3L - Oil Leak Between Crankcases
Yes stay away use the old crap mine has only not leaked for the last twenty years with sili gasket you have no need to put a lot on so it leaks out just enough to cover one side with a thin coat or go down the old way and have it leak again
