oil leak fuel pump-C-1

[Richard P.]

Oil is leaking out of vent holes in the top casting of my long screw fuel pump (1956 -265 cid). I replaced the top with one from a pump I had on the shelf that was OK when removed from a different engine. Soon I had the same problem. Engine oil pressure is 15 PSI at 600 RPM and 40 PSI at 3000 RPM. Am I missing something? A coincidence? Thanks for any insight

[Clem Z.]

Re: oil leak fuel pump-C-1

Oil is leaking out of vent holes in the top casting of my long screw fuel pump (1956 -265 cid). I replaced the top with one from a pump I had on the shelf that was OK when removed from a different engine. Soon I had the same problem. Engine oil pressure is 15 PSI at 600 RPM and 40 PSI at 3000 RPM. Am I missing something? A coincidence? Thanks for any insight

make sure the oil drain back hole in the push rod cavity is not blocked

[Richard P.]

Re: oil leak fuel pump-C-1

Thanks Clem, Will check it out this week. BTW My picture at Watkins Glen was taken about 5 years ago.

[Roy B.]

Re: oil leak fuel pump-C-1

Your pump seal is worn

[Edward J.]

Re: oil leak fuel pump-C-1

Richard, I think Roy is correct, even with a pin hole in the pump diafram it will draw oil from the block push rod area and pump it out the air bleed hole. Ive seen this before with alot of mechanical pumps.

[Anthony P.]

Re: oil leak fuel pump-C-1

I just had that same exact problem and had to replace my pump. Just a very small amount of oil was comming out.

[Richard P.]

Re: oil leak fuel pump-C-1

Followed Clem's advice since same problem had occured with two different pump heads. There did seem to be some interference when I pushed a flexible jacketed wire into the drain hole. Besides this was much easier than rebuilding pump. As indicated by article in recent Corvette Restorer. It took about 500 miles for the leak to reappear so it may be a couple weeks before definite answer to this question. Thanks for all the responses.