Classic/Antique Car Repair: Ford Mustang Fuel system, engine oil pan, fuel pump filter

Question
I have a 1965 mustang, 4bbl 289 (Not Hi-po).  Currently I have an original style fuel pump / filter housing that is spitting fuel out a hole in the top aft part of the pump.

What is this indicative of, and is there any adjustments that can be made to the pump to stop this?  (although it leaves my oil filter nice and clean)

Thanks,
Marty Hill

Answer
This is actually a very common way for a fuel pump to fail.  There is no way to fix it other than to rebuild or replace the pump.  These are readily available brand new from most auto parts places; and they are cheap and easy to change.  The cost will be under $50 plus labor.

The cause of the gasoline coming out the vent hole on the side of the pump is that the internal rubber diaphragm has failed and is allowing gas under pressure to get into the actuating arm chamber.  This may also be allowing gas to flow into your engine oil pan, so you must NOT drive the car this way, and you must change the oil and oil filter immediately after you replace the pump.

Dick