Mechanics

FUEL PUMP ISSUES ONCE AGAIN

1991 Nissan Pathfinder • 100,000 miles

So I have no idea why this is happening on a regular basis but I just had my 3rd fuel pump go out in my truck im getting really pissed off now and am tired of buying all these fuel pumps. I dont know what whould be killing them and im not sure what info is needed to help diagnose this problem other than it keeps happening.

if u have any ideas please let me know and if u need more info on it just tell me what u wanna know cause I have done more things in an attempt to fix this then I wanna type right now
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Scottscott07
June 29, 2012.




Have you determined how they are failing? Open circuit in the motors? Sparks like normal when you connect it to a power source but the motor won't run? Is the motor running but no fuel is being pumped?

If the motor runs but you get no fuel, you may be replacing just the pump inside the housing. That housing will have a pickup screen that can collapse or get plugged.

If the motor doesn't run but there is a spark when you connect it, the impeller may be getting stuck. Chrysler used to have a problem with that. By about the fourth or fifth pump in a couple of months, you buy one from the dealer and have no more problems. In fact, it wasn't that the pump came from the dealer. It was that the microscopic debris in the tank had all been collected in the previous pumps and any new one would have worked. Chrysler pumps are built with very close clearances to make them quiet but that leads to the impellers locking up from that debris. The cure is to have the tank steam-cleaned at a radiator repair shop, then install the new pump.

If you can't hear the motor run, connect it externally to a battery before removing it from the tank. If it does run that way, suspect a poor ground or bad connection in the 12 volt feed wire. Those can be irritated enough to make them work for a while when you remove the pump.

Caradiodoc
Jun 29, 2012.
OK I've been told to clean my tank already and currently am doing so but I'm wondering if it could be the fuel pump housing that is bad because I had to go get one from a junk yard cause the one I had in the vehicle had a melted wire on it and wouldn't work. So is there anyway that could be the problem
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Tiny
Scottscott07
Jun 30, 2012.
Sure, but I'd have to see it. Wires for the fuel gauge sending unit won't melt because there is very little current going through them. The pump motor, however can draw 6 - 10 amps and that will overheat terminals that have a less than perfect connection. That goes back to the last paragraph in my first reply.

Caradiodoc
Jun 30, 2012.

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