mechanical fuel pump question
 

I've got a carved 86. It has functional dual tanks and a quadraje 825 cfm? Its the big one. Anyway I keep burning up today's junk fuel pumps they sit over winter and done-zo I can hear my tanks switch and I have at least 5 gals of fuel in tank. But no fuel delivery. My question is on the three orafice pumps am I correct in saying one line in for inlet one for return and one for the feed to Carb. Do I need the return line? If that's what it is. I ask because I have a nice Carter pump on the shelf but its only two orafice. Can I use it?
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Re: mechanical fuel pump question
 

I'm running a dual tank truck with a two line pump. In and out. Just block off the return line and your good
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Re: mechanical fuel pump question
 

I am also using a high preformance fuel pump on my 85/ with Dual Tanks. Same as INSID, just plug that smaller (1/4 inch iirc) line and your good.

Re: mechanical fuel pump question
 

Thanks guys I was figuring but sometimes the unknown can happen and asking is easier than fixing. LOL thanks again
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Re: mechanical fuel pump question
 

Check the fuel lines on the suction side of the pumps;we are finding cracks in the lines that allow the pump to suck air and will act like a fuel pump failure.
Late model fuel pumps from brand name suppliers have internal components that are compatible with todays fuel so you should not be seeing multiple failures.
It is possible to have issues with trucks sitting over the winter;a fuel stabilizer should be used for storage over 6 months.

Re: mechanical fuel pump question
 

I threw my Carter pump on this morning. And plugged the return. Now I've got a major back firing issue especially at idle. Some background....a just changed intake and Carb a couple days ago. Its got a fresh quadrajet on it. Is it possible with out a return that the pressure of a high output after market pump is to much and forcing to much fuel in to detonate violently when that cylinder hits?
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Re: mechanical fuel pump question
 

Ha never mind I had 1 n 8 backwards on the dizzy Not sure how but oh well
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Re: mechanical fuel pump question
 

Just for background information, too much fuel delivery will not cause it to detonate. It would run like crap, it would idle very rough if it idled at all, and it would bumble and accelerate very slowly and be overall down on power.

A LEAN condition, not enough fuel, would cause detonation and backfiring.