Hey Ya'll,

I did am an electric fuel pump conversion last year, with a facet duralift. Worked fine until recently. I put the pump in the engine compartment, I think this was a mistake.

Recently, truck has started bogging down on hills and stumbling at idle. Seems to happen at random, though getting worse and more frequent.

I noticed some air bubbles in the fuel bowl on the lift pump, and have been hoping this is the culprit, as I really don't want to replace the IP.

This weekend, I moved the lift pump back to about 16 inches from the tank. Front tank only, no FSV. I also replaced the fuel supply, and main return line with 3/8s rubber fuel line.

Seems to work, though it still stumbles on a cold start (mostly if I engage the cold advance), and seems like more of a dog than ever on the hills. (I live in the olympic mountains, so no real way to avoid hills.)

I imagine the 10,000 miles of sucking instead of pushing fuel has taken some life out of that pump.

Im also wondering if the slightly larger return line could be causing some of this? Would having a 3/8 return line reduce fuel pressure @ injectors, and make the thing more of a pig on the pulls?

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Thanks,

hj

(PS I just scored the 85 Econoline electrical shop manual if anyome needs it.)

 

im running a 3/8" return line without issues.
altho rubber fuel line and hose clamps are not in my vocab,
make sure you have the correct barbs to ensure it don't suck air

 

I figured it wouldn't be a big deal, but wanted to double check w/ all you fine folks.

I should have been more clear, it was losing power/stalling, then surging on hills.

Now it climbs up steady, at about half the speed of a sloth. It's always been a pig, maybe I just forgot how bad.

 

I have never had a problem

 

mine has been mounted on the filter head for over 100k miles without any issues. it sounds to me like you were sucking air.

 

Yeah, air for sure. Ran my route today with better performance, but still a bit finicky on the big pulls with a full load. (This is a big ol box truck).

I'm guessing I wore that fuel pump out by having it so far from the tank. I got cocky and mounted it at the high end of the spec (120 inch dry prime), then ran it 5 days a week for a year...

1 hour, 8 inches of angle iron and four bolts later I've got it where it should have been all along. I think the bracket in the engine compartment cost more and took more time...

Got the new lift pump ordered tonight. Hopefully I'll get a bit more life out of this one by respecting the limits of the equipment.

I also noticed a but of oil coming up from the inside valve cover bolts on the driver side... so looks like I've got another project there too. Still holding as much oil as it normally does, but probably better get some new gaskets.

guess that'll be my next post.

 

snug the gasket bolts up first.
my 88 is still wearing the original valve cover gaskets with 495,000 miles on the engine. every year or so i need to give the bolts 1/4 turn. they just loosen up a bit over time.

 

Aye, that's thrifty, mon!

 

I'd be checking the tank to make sure the pickup is still OK and not partially clogging.

I've seen that on two trucks now; issues where it'll pull fuel, but not quite enough. So it'll run, but not have nearly as much power as it should. Same as you are getting.

 

that would usually cause enough of a vacuum in the line to turn the fuel filter light on though.

 

If it's the '85 in the OP's profile, there isn't one.

 

In theory, you are right. Assuming:
1. The sensor still exists(either didn't exist in the first place, or was removed)
2. It still works.
3. The wiring still works as well.

That's a pretty high barrier to cross in something this old, something that wouldn't get fixed if it broke because it's almost never used.