fuel pump question

Hi,

I tested my fuel pump, and it is weak. The quantity of fuel is around 1L/min, but the pressure is between 20-25 psi.
So, here the fuel pump costs around 150$ or if I order it form rockauto then it comes over 120$ (expensive)
Is there any possibilty to replace it with other cars fuel pump? Also it has in tank fuel pump, is it possible to build it out of tank?

Any expierienses?

kkerem said:

Hi,

I tested my fuel pump, and it is weak. The quantity of fuel is around 1L/min, but the pressure is between 20-25 psi.
So, here the fuel pump costs around 150$ or if I order it form rockauto then it comes over 120$ (expensive)
Is there any possibilty to replace it with other cars fuel pump? Also it has in tank fuel pump, is it possible to build it out of tank?

Any expierienses?

Click to expand...

That's about what the pumps cost here. You could theoretically use almost any other (external) fuel pump and just mount it externally and then just make a pickup inside the tank so that it's always where the fuel is.

Also what year is your jeep? Check the voltage at the pump and make sure you're getting 12V on the pump: maybe your wiring is shot someplace or maybe your balast resistor is not making a good contact (btw, not all jeeps have a balast resistor)
Lastly check the fuel filter to see if it's not clogged. Older jeeps have the fuel filter on the frame rail on the drivers side and they also have a "sock" on the pump intake, newer ones (97+?) only have a "sock" on the pump intake in the tank.

Before figuring out that my jeep may have fuel pump problem I change allmost anything, fuel filters, wires etc.
I havent checked does it have 12V, this is good point to check.

One more question, how big should be the resistance of the resistor? Also, what happens, if I just pass the resistor? Just if the fuel pump is too weak, may be passing the resistor helps.
One guy here sells me the pump, but it takes a little time, but I hate to drive, when it is choppy

The resistor reduces the voltage to the pump at idle after about 1200 rpm there is a relay that raises the voltage to 12v I have had mine bypassed for some time now without any problems.

73's KG4BET

I am having the same problem 1987 4.0 Renix system. I can't find the resistor, there is no resistor on the driver side fender, there is a relay and the EGD solonid, I even pulled the washer bottle, relay pulls in for three seconds when key is turned but no pump sound. Pump is new, so are filter and relay.

Hi again,

can anyone tell is the AIRTECH?, not sure if I wrote it correctli, is a good fuel pump or?

langer1 said:

I am having the same problem 1987 4.0 Renix system. I can't find the resistor, there is no resistor on the driver side fender, there is a relay and the EGD solonid, I even pulled the washer bottle, relay pulls in for three seconds when key is turned but no pump sound. Pump is new, so are filter and relay.

Click to expand...

There is no resistor on an 87, which is why you can't find it.

kkerme: I had a simlar problem you had on my 89 XJ. I figured it was the fuel pump going bad. So I planned to replace the pump... but I decided to pull the pump first before buying a new one, NAPA told me there were 2 diffrent ones for my Jeep and should get the right one.

So.... I pulled the pump out of the tank and immediatly noticed the rubber fuel line was not completly on the pump all the way. So I slipped it back on and tightened down the clamp, reinstalled the pump. BINGO ! I had my fuel pressure back and my Jeep was all good to go again

I'd say its worth a try to check the hoses on the fuel pump before buying a new one. Its not that hard at all to get the pump out.

Dan

Matthew Currie said:

There is no resistor on an 87, which is why you can't find it.

Click to expand...

I traced all the wires and figger that out. Is that why the fuel pump for a 87 is the $189.00 Bosh unite?