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MG MGA - oil leaking from Bellhousing

Finally, after rebuilt motor and chasse I just had to take her for the first spin. Yee ha! Quite a thrill.
My question is:
It appears a little bit of oil is leaking from the bell housing. Could this be from the tranny of which I did nothing to, or my main seal which needs breaking in? Or (Please say it ain’t so) a damaged main seal. Your input is appreciated, Bill
Bill

Bill, there is no rear main seal in an "A" engine, just a reverse scroll and an oil slinger built on the crank. Excessive clearence between the scroll on the crank and the rear main bearing block could result in leakage, it shouldn't be any worse than it was before you rebuilt it. A pluged oil breather on the engine can also cause excess crankcase pressure which may force oil out the rear main. It could also be the front trans seal. Once you run it long enough to dirty the engine oil, check your leak for color, the oil in the trans stays rather clean compared to engine. Any time I pull an engine I replace the front trans seal weather the car is new, old, stick, or automatic. Its really cheap insurance given the cost and pain of pulling the engine.
John H

Thanks John! I will try and determine the color tonight!
Bill

Are you absolutely sure that it is coming from inside the bellhousing. New clean engine and clean oil becomes very difficult to locate an exact source. Common places are tappet chest side covers and of course the oil travels down the block, round the sump joint and drips from the lowest point - the bell housing. Make sure also that the sump joint is dry. Check the front of the engine backplate for tell tale signs.
Iain MacKintosh

I "cured" nearly all my MG oil leaks by replacing the front oil seal with a "RED" (Better Quality) seal in place of the "BLACK" one, and coating all my cork gaskets and paper seals with DOW CORNING DC-4 SILICONE GREASE before assembly. DC-4 is especially good for the VALVE COVER GASKET. That is Silicone GREASE, NOT the Silicon RUBBER, which I.M.H.O. is useless as a sealant! Also works great for lubricating the distributor Cam, used sparingly. Some claim it will keep water out of the Electrical Pop Connections, too, but I've not tried this.
OLD BILL-67

Thanks All!
It was the Front Tran seal which will require me pulling the engine AGAIN!. So I am going to try to get right on this while I am still trying to convince myself this is supose to be a fun hobby!

PS The side covers were also leaking but required just a little tightening.

Thanks again, Bill
Bill

This sould serve as a reminder to us all. When there is access to an old seal replace it. The labor you save will be your own. Penny wise is pound foolish.
Randy
R J Brown

This thread was discussed between 31/10/2005 and 12/11/2005

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