Britbike forum Forums British Motorcycle specific Brands Bsa bulletin board a10 chain case leak

hi all im new to the forum, can any one please help with a question i got.my bike is a gf52 plunger, i am having trouble sealing my chain case housing and i have been recommended to use a cork gasket as i have tried a card and liquid gasket , i can only find one to fit a swinging arm bike while mine is a plunger is the gasket the same for both types what is the difference or has anyone any other ideas to solve the problem ??, many thanks gary...

Gary;

The plunger has a shorter chaincase than does the swingarm as the gearbox is bolted right to the back of the engine. You should be able to dress out any imperfections on the cover using a large piece of plate glass and a sheet of fine emery paper. With modern gasket material to make a gasket you should be able to make it oil tight. Do you know where the oil is coming from? The cover seam? Could it be from the where the mainshaft enters the chaincase area behind the clutch? Is there a breather pipe?

Gordo

thanks gordo, the leak seems to be coming from one of the screw holes at the bottom , i have tried gaskets on each face to no avail, any way off to italy tomos for a week on holiday will pick it up on return thanks gary...

Where, exactly, is the location of the leak? Are you certain it's at a screw hole?
Gordo's correct re resurfacing the cover. A warped inner cover or a crack at that screw hole can also create the problem. Multiple gaskets will not avail you not; a gasket is only intended to make up for manufacturing tolerance spread.
The root of the problem is right there in front of you. Look closely and you'll find it.