<VV> Question from Newbie concerning annoying oil leak

[solidgrd25 at comcast.net]

Greetings!

I'm a newbie to the ownership of a 64 convertible equipped with a 95 HP engine and 4 speed manual trans. The previous owner rebuilt the motor about two years ago and did not drive the car much since then. The motor is leaking a fair amount of oil between the engine and the clutch housing as the car is being driven... otherwise it runs fine. This leak occurs while the car is running and the engine is warm. The motor does not leak when the car is parked and turned off. I have checked the plugs for oil pooling and have found nothing. I'm concerned that this may be a crankshaft main seal leak? The thing I'm puzzled about is that the oil is a dark grey and does not smell like regular engine oil. Could this possibly be a transaxle oil leak instead of an engine main seal leak? The engine oil is fresh as it was just recently changes. I would appreciate any feed back and thoughts on this concern. Thank you in advance for helping a frustrated "newbie"

Kind regards,

Serge