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SPFI Swap Fuel pump issue


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Hello, I have an 86 gl wagon with a new ccr engine, a 3.5/4" SJR lift, we put in power steering and recently swapped the leaky stock carb for a spfi that came off an 89 coupe.

 

The problem is we put in a brand new $250 fuel pump, we had a return line hooked up wrong so we ended up filling the charcoal canister with gas and had to put a diff one in. Then it ran like a champ with power and increased gas mileage. Then the problem started, it not wanting to start unless it was cranked on. One day the fuel pump stopped. I looked up on here and found out the pump burnt out and we got a replacement and it fired up again. But I knew there was still an issue that was unresolved. I drove it anyways since we didnt have a back up car and now Im back to it having to be cranked and cranked til it fires, which means the pumps shot again. What would cause this? We followed the spfi conversion and cant think of anything that would be wrong. Would one of the new sensors be burning it out? Theres also a dead spot in the throttle when you step on it but I think thats unrelated.

 

We are at our wits end with the car. Its my daily dr so I really need it running.... Thanks for any help

 

If you want to email instead of replying my email is bowlinatwildbluedotnet

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Volts & amps?

 

Temperature of the pump?

 

Fuel pressures?

 

Return lnes clear?

 

We are going to need more info.

 

I sugest you get some used fuel pumps or start using the Ford F150 pumps that are much cheaper.

 

The pump's are simple rotory vane pumps - they are cooled by fuel flowing through them. If there is not enough fuel flow through the pump they will overheat and fail.

 

GD

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Long cranking w/fuel injection usually means the check valve in the fuel pump doesn`t hold pressure in the fuel line w/the engine stopped.Normally unrelated to fuel pump life,but dirt /rust in the tank could be an aggravating factor for both.I`ve had check valves fail in new pumps.

 

Try priming the fuel system by turning the key to the "on" position for a couple of seconds before cranking to save starter life.

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I'll start checking things out. I dont think we have checked fuel press. or temp of pump etc....

 

As for the cranking, its a symptom that it did last time too, one month ago, about a month after swapping, it starting hard starting, long cranks and I found it odd but it still ran. Then about 2 weeks after the hard starting and getting harder to start, it died and would not start. We toke the pump off and tested it, dead in the wind. So we thought maybe it was just bad luck and tried just changing it. At first after the change it was harder starting, then it came back to normal. Now starting last week its hard to start just like before, so Im afraid the pump is gone again. A problem with the pump now is it doesnt start like it used to when you turn the key on. Only after cranking for a while does it prime it enough to run.

 

I was wondering if there is something electronic thats causing it to go out.

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Try priming the fuel system by turning the key to the "on" position for a couple of seconds before cranking to save starter life.

The fuel pump only runs when the engine turns, on the SPFI .

 

Check the screen on the fuel tank side of the pump make sure its not stuffed full of crap. Make sure there are no kinks or tight bends in any of the "new" plumbing you installed.

I had to replace my return line on my SPFI swap with a larger one because I was running at 30+psi fuel pressure at idle. I replaced everything up to the nipple on the tank and that solved it. The origional return line on my car was smaller than 1/4"

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It must have had a blockage.

It is possible, though I tried to blow it out with bursts of compressed air. It seemed like there was flow there. But it made no difference.

 

Another thought on this thread... Since the stock EA81 nonturbo fuel tank wasnt intended for F.I., running your tank on less than a 1/4 at all times probably wont be good for the fuel pump either. There are no baffles in the tank, so hard corners, stops, hills, etc. may make the pump run dry for short spells. I would think youd notice the dry spell. Its a long shot but a thought.

Edited by ihscout54
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