Classic/Antique Car Repair: Oil Pan Leak, oil pressure sending unit, thick oil

Question
I have a 66 Corvette and changed the oil for the first time since I owned bought the car

The old oil that came out was really thick. After my oil change I have a small drip around the pan. I sure I the oil pan bolt is secure into the pan

Any suggestions on what my problem is

Thanks  

Answer
It all depends on where it is leaking from.  If it is coming out around the drain plug, probably the gasket is bad, or else the threaded fitting that the plug screws into is not sealed where it is welded to the pan - which is a defect in the oil pan itself.

If it is dripping from the back of the pan, back where the flywheel is, the leak could be a bad rear main bearing seal, or it could be running down the rear of the engine block from a leak up top somewhere - for instance the oil pressure sending unit.  

If it is leaking around the edges of the pan, the pan may be loose or the gasket may be bad.

The fact that it had really thick oil in it is a worry. Usually, people put extra thick oil into an engine to hide some problem - you may have to take the car to a mechanic and have him check the bearing clearances and verify that the engine is in OK condition.

Dick