cwhitt87xj

Hello everyone, I'm once again going to try to get my cherokee running again. I made a post back last year about my cherokee burning fuel pumps up constantly, well I guess thats whats happening. I have been through 3 fuel pumps in the past 6 months and gave up on it. Anyone got any recommendations? This coming weekend I plan to drop the tank and clean it out and order another fuel pump, prolly an airtech from autozone. The question that I asking is why do the fuel pumps keep going out? I have checked the fuel pump relay and it is good, what else should I do? I love my jeep but I just can't afford to go pay a mechanic big bucks right now, college is expensive! Sorry I wrote so much, I just can't figure out whats wrong with my baby!

EVcherokee

I know renix fuel pumps use a ballast resistor located next to the air box....a lot of guys just bypass this and do fine. Do you have a ballast resistor? from what I understand its there to protect the pump.

I've also heard that the Bosch pumps are the only way to go.

cwhitt87xj

Is that the ceramic looking thing on the fenderwell? If so, I have one of those, It has an orange and black wire going to it, are you saying I should cross these? Were can I get a bosch pump at?? I'm excited! I might get this bad boy going again!

EVcherokee

No, what I"m saying is that I think its there to protect the pump, but they are prone to breakage, because their porcelain, thats why guy bypass them. Have you check to see how many volts your getting at the feed wire for your pump?

I think Napa and Carquest carries Bosch pumps. Those are the only two walk-in stores I go to. Checkers/O'Riley and Autozone......to many bad experiences with highschool kids behind the counter. I've seriously considered throwing band new bad parts through the front window on more than one occasion

cwhitt87xj

Alright, I did check the voltage a couple weeks ago and it was getting 12 volts and all of a sudden it went off, I'm guessing that means the pump is done priming or whatever it does, but the pump doesn't work. I know it needs a new pump but I checked the voltage anyways. Back last year it was only getting like 6 volts back there so I'm confused. The ballast isn't broke on my cherokee so I have no clue whats up with that!

EVcherokee

I'm confused too, you might have some electrical diagnostic work ahead of you...One thing that I've heard kills pumps is running all the time near empty too. Maybe somebody else can chime in..

rich

The gas in the tank is what keeps your pump cool if you only run a 1/4 tank of gas all the time you will burn it out.Trace your wires and look for bare wires.

cwhitt87xj

I never run it below half a tank. I've got a long weekend ahead of me I guess!

freegdr

check the voltage with a meter on both sides of the resistor

rednekwizard

Put it on a relay toggle setup, I have ran for years that way instead of chasing shorted wiring. If you do it right you shouldn't have to worry about it.

cwhitt87xj

freegdr, what should the voltage be when I check it? If it is too low what should I do?

cwhitt87xj

rednekwizard, how exactly do you do what you siad? Run a positive and negative wire from the pump to the battery and then run a wire inside the cab for a toggle switch? When you do this do u just turn the toggle switch on when you get ready to go somewere and flip the switch off when are through driving?

rednekwizard

Yup, did it with my 86 Z-28 that I just sold and it worked fine, just have to get a good high amp switch and not one of those cheap plastic things from autozone, I used a big 30 amp and wired in a relay, it never overheated the switch and worked perfect to keep fuel in the rails.

All i did was clipped the wires at the pump, leave a little on the pump for splicing just in case you ever wire back, and ran the original ground, ran a new wire from the fuse box to the toggle in the dash, ran the wire from the toggle to the hot wire on the pump, ended up tracing my issue back to some idiot stealing my car a few years ago and they shorted everything out trying to hotwire it.
The ground can be anywhere on a good bare portion of steel or you can just leave the ground connected on the pump. or wire it backwards and use the toggle as the ground breaker.

cwhitt87xj

I got to work on my jeep some this weekend and I decided to pull the fuel pump out and drop the tank before I checked any wiring. And I'm glad I dropped the tank, the gas is so bad and old that it has gummed up inside the tank, ate the hose's up on the pump, the strainer on the fuel pump fell down into the tank on it and pretty much the whole sending unit has gummy gas all over it. But wait there's more! My tank is full of rust!! I got the pressure washer out and poured some chemicals in it that my dad washes equipment motors down with and started spraying it out, I got all of the bad stuff out, but there are small flakes in it and the rust that is still stuck to the walls of the tank. I'm back at school now, so I have to wait until next weekend to start back on it. Any tips on getting rust out of the tank? And how to clean the sending unit up. Thanks.

freegdr

it should have 12 volts coming in and 12 volts going out you states it had 6 volts last year that will burn pumps up just as quick as getting to much surrent . Id replace it when you do the pump