fuel pump went bad today

[Car RamRod]

My fuel pump decided to give up on me today, my truck's down at work now.

 

I called the parts distributor and they have two pumps listed, which are not interchangeable. One is a walboro and the other a bosch. I'm using a pump from an 87 in my truck, is there anyway to tell which one I'd need before taking mine out?

 

Also, I put the 87 pump from a smaller tank, into the 18 or so gallon tank in my 86, could that have caused a problem?

 

Thanks,

Matt

[Pete M]

Are you sure it's the fuel pump and not the relay or wiring?

[Car RamRod]

I have juice and a ground right up to where it goes into the tank. I don't know what else it could be.

[comanchedude]

RockAuto has a good deal on a complete Fuel Pump Assembly

 

 

AIRTEX Part # E7091S More Info {Fuel Pump Assembly (Pump & Sending Units)}

Choose:

 

Part Image

$63.79

[MiNi Beast]

 

Also, I put the 87 pump from a smaller tank, into the 18 or so gallon tank in my 86, could that have caused a problem?

 

Thanks,

Matt

 

 

 

No that shouldn't make a difference your just holding more fuel is all. But if you didn't change the pump filter that could have cloged it and burned it out. But do you hear the fuel pump at all when you turn the key on? If not and you got power to tank maybe wiring came loose on the inside. And how did she sound before it went out? Or did it just not work at all instantly?

[Car RamRod]

But if you didn't change the pump filter that could have cloged it and burned it out. But do you hear the fuel pump at all when you turn the key on? If not and you got power to tank maybe wiring came loose on the inside. And how did she sound before it went out? Or did it just not work at all instantly?

 

There's no noise at all when I turn the key to on.

And it started as usual an hour earlier, then like that.....dead.

[JeepcoMJ]

what motor is it?

 

I have a brand new, zero miles but previously installed fuel pump (junked the truck so I could build the 3800 to 4wd with the parts).

 

-Pat

[MiNi Beast]

yeah what JeepcoMJ had said what you working with? Motor? Tranny? Anything out of the ordinary leading up to this? And you said it started then just died? So it sometimes runs then like stalls out and can't start? Have you checked fuel filter and have you checked the fuel pressure?

[TNT]

FYI, if you need to drive it to were you need to work on it have some crank it while you hit the tank with a rubber mallet. It cause the brushes to move around and the pump will start running. Just don't shut it off untill you get to where you need to work on it.

[jtdesigns]

FYI, if you need to drive it to were you need to work on it have some crank it while you hit the tank with a rubber mallet. It cause the brushes to move around and the pump will start running. Just don't shut it off untill you get to where you need to work on it.

 

And have someone following you! :cheers:

[Duner]

I posed this question a couple of weeks ago about the:

 

AIRTEX Part # E7091S (this pump is sold by every auto store and rockauto is the cheapest source if you have time)

 

This assembly does not fit my 1990 short box comanche pioneer - it sorta fits after you relocate the filter to the other side and fool with the sending unit and bend the arm to better angle the rubber isolater into the hole in the tank.

 

I'll stand by my experience with this pump - it is a cherokee assembly and does not properly fit the comanche tank.

 

I will be pulling my airtex out this weekend and returning it to autozone and getting them to replace it because the sending unit gave up already.

I will then disect the new assembly and retrofit it to my original comanche bracket assemby and hopefully all will be well.

 

So if your sending unit works just replace the pump and filter sock and retain your original assembly.

[Car RamRod]

yeah what JeepcoMJ had said what you working with? Motor? Tranny? Anything out of the ordinary leading up to this? And you said it started then just died? So it sometimes runs then like stalls out and can't start? Have you checked fuel filter and have you checked the fuel pressure?

 

renix 4.0/ba10. It was running and starting just fine. Only thing out of the ordinary was that I was down at work to pick up my toolbox to bring home, so the truck was saggin back pretty well. Even though I had over 1/4 tank, I put 5 more gallons in just to make sure that wasn't the problem.

 

It doesn't start at all, it had been starting just fine, then all of a sudden, nothing. The fuel filter was changed 150 miles ago, and I don't get much fuel pressure at all at the shraeder valve.

 

Thanks for the heads up on that Duner, I'm gonna get the pump from the distributor at cost.

 

 

Thanks for the help,

Matt

[MiNi Beast]

yeah what JeepcoMJ had said what you working with? Motor? Tranny? Anything out of the ordinary leading up to this? And you said it started then just died? So it sometimes runs then like stalls out and can't start? Have you checked fuel filter and have you checked the fuel pressure?

 

renix 4.0/ba10. It was running and starting just fine. Only thing out of the ordinary was that I was down at work to pick up my toolbox to bring home, so the truck was saggin back pretty well. Even though I had over 1/4 tank, I put 5 more gallons in just to make sure that wasn't the problem.

 

It doesn't start at all, it had been starting just fine, then all of a sudden, nothing. The fuel filter was changed 150 miles ago, and I don't get much fuel pressure at all at the shraeder valve.

 

Thanks for the heads up on that Duner, I'm gonna get the pump from the distributor at cost.

 

 

Thanks for the help,

Matt

 

Assuming she is cranking and not just starting, have you checked the fuel rail when was running to see if gas shoots out> Check your CPS just in case, had that be the problem before. Check resistor on the fender wall. Just check everything before go tearing apart the tank and putting out $ for something your not totally sure about. As better to take extra time to check those little simple things then wasting money fixing something that doesn't need it.

[Car RamRod]

Assuming she is cranking and not just starting, have you checked the fuel rail when was running to see if gas shoots out> Check your CPS just in case, had that be the problem before. Check resistor on the fender wall. Just check everything before go tearing apart the tank and putting out $ for something your not totally sure about. As better to take extra time to check those little simple things then wasting money fixing something that doesn't need it.

 

I agree. I checked the fuel pressure at the fuel rail, and there is none; it just drips out. I haven't checked the CPS yet.....how do I go about doin this?

[HOrnbrod]

yeah what JeepcoMJ had said what you working with? Motor? Tranny? Anything out of the ordinary leading up to this? And you said it started then just died? So it sometimes runs then like stalls out and can't start? Have you checked fuel filter and have you checked the fuel pressure?

 

Assuming she is cranking and not just starting, have you checked the fuel rail when was running to see if gas shoots out> Check your CPS just in case, had that be the problem before. Check resistor on the fender wall. Just check everything before go tearing apart the tank and putting out $ for something your not totally sure about. As better to take extra time to check those little simple things then wasting money fixing something that doesn't need it.

 

X2. I know you said you have power and ground at the pump, but try bypassing the ballast resistor (inner drivers side fender, engine compartment) by shorting the two wires together and swapping out your fuel pump relay with a known good one next to it. Might save you some $$ and time.

[Car RamRod]

I tried a new relay there. (On the inside of the DS fender right). Didn't help. I'm gonna bring it home in a while so I'll have a better idea.

[MiNi Beast]

Assuming she is cranking and not just starting, have you checked the fuel rail when was running to see if gas shoots out> Check your CPS just in case, had that be the problem before. Check resistor on the fender wall. Just check everything before go tearing apart the tank and putting out $ for something your not totally sure about. As better to take extra time to check those little simple things then wasting money fixing something that doesn't need it.

 

I agree. I checked the fuel pressure at the fuel rail, and there is none; it just drips out. I haven't checked the CPS yet.....how do I go about doin this?

 

 

Pretty much first check to see if it's tightly screwed to the bellhousing then unscrew it and check with a good one, there is a way to check it but I've never relied on that, I always just bought a new one for thirty dollars. The CPS is worth more to just trough money at even if it's still good,you can always use a new one and an extra one at that, as well as it's a cheaper part. But like I said check those other thing under the hood first. Perferbly the resistor. My proplem ended up being that resistor, after I had replaced the CPS, but I didn't tear into that fuel pump like some thought it was. You seem to get gas just not all the time, so got to follow the system to elimanate problems.

[Car RamRod]

I'm not really sure if we're on the same page here......the engine does not start at all. It turns over but never fires at all. Even when I'm cranking, fuel pressure at the rails is nothing.

[MiNi Beast]

I'm not really sure if we're on the same page here......the engine does not start at all. It turns over but never fires at all. Even when I'm cranking, fuel pressure at the rails is nothing.

 

 

 

Right but do you have spark tough? You must check the easy stuff before tearing things apart. Check spark if you have that then check fuel.

 

Ok pull the Fuel filter line and try staring get any gas, no then replace the damn pump.

 

:headpop: I hate changing the fuel pumps, better to pull tank trust me, Changed mine out six times before changing the gas tank out with new pump/unit.

[Car RamRod]

I'll check for spark.

 

I just hauled to truck home from work. I picked up a replacement pump, so I'll knock the feed line off first and see if the current pump pushes any gas out with the key on.

[CWLONGSHOT]

I changed mine last summer easily. Never had to touch the tank!!

 

Good luck.

CW

[MiNi Beast]

I changed mine last summer easily. Never had to touch the tank!!

 

Good luck.

CW

 

 

 

 

 

 

JK. Changed first two out no problem too, but the third was a pain so just puled tank to do it and that way I could inspect the tank inside and out before new pump went in. And found it to be less stressful then putting a kink in my neck. But its one thing if you got good amount of gas in it.

[CWLONGSHOT]

Hell yea... you NEED TO DO this when the tank is near empty!!! don't even think of dropping the tank with a large amount of fuel in it!!! :eek: :eek: :eek:

 

In my case, it went very easy with out dropping the tank.

 

BTW, why the hell did you have to change your so many times????????????

 

CW

[Car RamRod]

uhhh I got it up on the lift today, and bam.....turn the key, fuel pump on, and she fires right up :nuts:

 

I pulled the pump anyway, and there were no loose wires, grounds, etc., the sock was still attached and not dirty, and everything seemed as it should be.

 

I want to get to the bottom of what got me stuck the other day still. I'm gonna order the correct pump and put it in regardless. Any thoughts? What's the story on that CPS sensor?

 

 

thanks for all the help,

Matt

[MiNi Beast]

Hell yea... you NEED TO DO this when the tank is near empty!!! don't even think of dropping the tank with a large amount of fuel in it!!! :eek: :eek: :eek:

 

In my case, it went very easy with out dropping the tank.

 

BTW, why the hell did you have to change your so many times????????????

 

CW

 

 

Some moron before me pulled the tanks and to clean it I guess cut the top of the gas tank off then did welded it back together. Little did I know this but the pump kept burning out, So said screw it, thats when I finally pulled the tank, to make sure it wasn't rusty on inside as someone suggested. So bam I instantly saw the problem, one hell of shizty weld job, I can't weld but I could have done better with JBweld, So anyways went to rinse her out and found nice 7 holes throughout the weld lines. Yeah so rinsed everything out in a big storage bucket to find I had two handfuls of sand in the tank. :mad: So didn't have the $175 TO BUY a tank so rinsed it out real good, put a tube of seal all over and around the seams, let dry then a can of rubberized undercoating over the whole tank. Beautiful fixed never had a problem for about a year. Then was picking engine up from a old MJ guy and he had a brand new tank said only $50, so I got yeah. But the sending unit in it was rusty so hole came tough to spit gas, so have seal all and JB weld on that holding it till Spring to change it out.

 

 

 

And the CPS retards the engine thingy and makes it fire when the gas is shot in, very important, been dealing with it for the last couple months to finnaly have it fixed. CHECK IT! CHECK IT!