Actually, there is NO oil seal as such. Oil is rerouted back into the engine by a spinning ring. This ring is part of the crankshaft and as oil tries to move to the rear, it is deflected by this spinning ring and tossed into a circular trough then directed back into the crankcase.
Do not rely on the oil level floater, it is notoriously inaccurate.

Where Are You From? Texarkana, TX

Do You own a car built by Durant? Several