flap valve in crankshaft allowing oil into chain case

Information relating to the Matchless G9 or AJS Model 20 500cc twin
User avatar
ajscomboman
Member
Posts: 3963
Joined: Mon Jan 01, 1990 12:00 am
Location: HAMPSHIRE UK

Re: flap valve in crankshaft allowing oil into chain case

Post by ajscomboman »

gtx469 wrote:I see a lot of posts saying that there is a spring in the flapper valve crank nut breather. I just did the oil seal mod to my 61 G9 and my crank breather nut does not have a spring in it, just a small stainless steel plate held in by a peened edge ring. seems to work just fine blowing air out to case but seals going in. Is this nut something that was changed in 61 era?
The spring was done away with 1957 I think.
Locked