Noticed I had a fuel leak yesterday. Popped the hood and fuel was squirting out around the o-ring on the top of the filter housing and out the banjo bolt washers on the inlet from the lift pump. I replaced the filter today and no more leaks.

I've got the Edge sender hooked to the VP inlet and an Isspro mechanical guage hooked to the fuel filter housing outlet. Edge was showing 14psi at idle and the Isspro was showing 15.

What I'm confused about is I still had good fuel pressure past the filter, but yet I was still blowing out the seals. What would cause those to leak?

 

No ideas?

 

Was the old element ripped?

 

Had it been ripped there would be no reason for a leak.
Was the pressure reading higher before? If it decreased and leak appeared, the filter just got restrictive enough I think.
What is your lift pump? A stocker I think has a bypass and won't blow seals. If it is a stocker I would think the o-ring just bulged out for some reason. If you had a gauge pre- and post filter you would know for sure. There is a spec in FSM for max pressure drop across the filter, I think 1 psi? I can't recall.

 

Max. pressure drop acroos the filter is 5 PSI.

 

The leak will not be caused by a plugged filter. Loose banjo bolts is my guess.

 

Nope, the old element wasn't ripped. Grey and dirty, but still intact. Banjo bolts are all tight.

I don't have a pre-filter guage, just 2 post-filter. I have a stock Carter lift pump. Normal pressure at idle with a new filter is 15psi and that's what I was showing on both guages even with the leaks.

The housing was leaking both at the banjo fitting at the inlet and out the o-ring on the cap.

Only thing I can figure is the filter was causing enough restriction, the pump was pushing higher pressure to compensate. How I don't know, I thought they were a constant output pump...

 

Bizarre.
Oh well, at least you got it fixed!

 

Yeah, I'm glad it's fixed. Just really curious what caused it.