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Im not sure why my big block (1967 427/435HP Coupe) is leaking oil at the point where the bell housing and engine meet. I have attached a few pictures. Is this an easy fix, like a rear seal or something else.
i can see its not dripping from the top of the valve covers since that is clean and dry, though I do see some oil near the starter motor some of the time.
Any chance it's coming from the trans...leaking out the countershaft front hole and running down the bellhousing to where you see the drips? If so, since it's an interference fit, there is no fix other than to have the trans main casing bushed.
Hopefully it isn't from the rear main seal but not the end of the world if it is. Before you take that plunge, can you see down behind the intake to see if the rear seal (or silicone seal) is not working? Might be tough (or nearly impossible) if the BB ignition shielding is in the way. As for the valve covers, you said you looked and didn't see anything but since the valve cover flanges extend 'over' the sealing surface of the heads, you can reach down and run your fingers up underneath the edges of the valve covers to see if they are leaking.
When I got my 66 L72, now running a mild 396, the passenger side valve cover gasket was leaking quite a bit. The gasket turned out to be almost petrified, rock hard. Replaced it and no more leaks...well, no more leaks from that valve cover ;-).
Mike T - Prescott AZ
valve cover gaskets on stamped steel valve covers are notorious for leaking. I would double check them. I never had any luck with the rubber style. I always had good luck with cork. the only other locations are the oil plugs in the block and the real main seal.
I replaced the valve cover gaskets this summer with cork ones. I guess when i start it up next time, its in bed for the winter here in NH I will try to trace it down. I have a 4 post lift but really can't see where its coming from. Im hoping its not the rear main seal. After my last ride on thanksgiving morning I wiped it down but as you can see there is a drip on the end of the bell housing. I will wipe it down again and see if i can trace it.
It's a good chance it's the rear main seal. The lack of use on the cars, sitting for long periods of time, brings on the leaks as seals contract. Dennis
All the above are possible sources of a leak. You can rule in, or out, the transmission by giving the leaked drops a good sniff. Gear oil and motor oil dont at all smell like each other. Agree in full about cork gaskets for your valve covers. I never had luck with rubber ones, either.. Self stick cork seems to do a better job on the block valley surfaces (seal to the intake manifold) as well. Another place to look is the oil pan. Stock style 4 piece gasket sets are leak prone. You might have a leak at the back of the block where its joined to the oil pan.
427 engine leak help?
Dennis
