Oil leaking from fuel pump on my 67 mustang

[Loumav]

Hi guys,
First time posting.
I have had trouble with oil leaking from the mechanical fuel pump on my 67 mustang coupe. It was leaking around the rim where the upper and lower parts of the housing is sandwiched together so I replaced it with an aftermarket one. The new one worked well for about 50km but then it also started leaking as well, but through the two vent holes.

Anyone have any ideas as to why?

 

[B67FSTB]

2 different problems with the pump so I guess your new fuelpump already had a problem prior installation. I would install another new one.

Verstuurd vanaf mijn SM-A605FN met Tapatalk

 

[Starfury]

Hmm. Maybe blow-by?

What condition is the engine in? And do you have a pcv valve and breather installed?

 

[Loumav]

Hmm. Maybe blow-by?

What condition is the engine in? And do you have a pcv valve and breather installed?

Engine has done about 30K miles. Only driven on occasions. Has pcv valve which i also replaced and tried the old one again just to make sure. Leaked oil with both. Taking oil filer cap off does not or exhibit any back pressure through the covers.

 

[Horseplay]

Sad state of the parts quality these days would be my guess. If excess oil/crankcase pressure were a part of the cause you would be experiencing other signs/problems. As you describe the issues, it would seem to be simply poor quality control during manufacturing on the two pumps.

 

[Loumav]

Opened up the pump and the top half has two holes (breather) which seem to just vent the top of the housing. Seems that any oil pushed through the levering arm cavity would end up spilling out through these holes which is what I believe is happening. But the question is should oil be traveling into the housing to vent or is it a bad design? Maybe I should block the holes and try it again? Any thoughts?

 

[Loumav]

Opened up the pump and the top half has two holes (breather) which seem to just vent the top of the housing. Seems that any oil pushed through the levering arm cavity would end up spilling out through these holes which is what I believe is happening. But the question is should oil be traveling into the housing to vent or is it a bad design? Maybe I should block the holes and try it again? Any thoughts?