On my third fuel pump

[oilman]

I have a 91 2.9 ranger, I'm on my 3rd fuel pump. I installed the new pump it starts right up. Drive it a few times, let it sit for a few days won't start. Pulled the pump the motor was shot. This has happened 3 times.Relays are good.No ground fault that I can find. I hooked the pump up to 12v direct, nothing. I'm out of ideas. Can the computer be causing this?

 

[gabes2.3project]

i just went to the tech library and you might be having fuel inertia switch problems and as for benching the pumps im not sure why they wouldnt kick on for you

 

[WTF]

I have a 91 2.9 ranger, I'm on my 3rd fuel pump. I installed the new pump it starts right up. Drive it a few times, let it sit for a few days won't start. Pulled the pump the motor was shot. This has happened 3 times.Relays are good.No ground fault that I can find. I hooked the pump up to 12v direct, nothing. I'm out of ideas. Can the computer be causing this?

When you bench tested the pump did you try reversing the wires also? Are these new pumps you're buying? When you buy them are you sure that it's the correct pump in the box for your truck? Just stabbing in the dark here.

 

[oilman]

yes I did reverse the wires. The pumps are all new, warranty has covered the replacement. I did jump the inertia switch it was ok. This really has me stumped.

 

[WTF]

The pump should've been humming when you hooked it to 12v directly. Check the circuit at the plug that goes into the pump when the key is off to see if it's being fed voltage.

 

[Bogus123]

It sounds like one of 2 things to me, either it is getting excessive voltage, (bad regulator in the alternator) or the unit is continuing to run after the vehicle has been shut off, and will overheat from no fuel circulating through the pump while it is running, the fuel helps to keep the internals of the pump cool, try pulling the relay out when shuting it off to leave the vehicle, and I bet when you come back and plug the relay back in next time and start it it will be ok, they trouble shoot from there.. Bogus123

 

[Duane867]

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Ditto

 

[oilman]

I'll try pulling the relay as soon as I exchange the pump and get it installed. If the pump continues to run after key is off other than a bad relay what would make it do that? Regulator causing relay to short out maybe. Thanks for all the info. I'll let you know how things turn out.

 

[naford]

Are you doing this with the bed on or off?