1996 XJ fuel pump and pressure regulator repair details

[Anak]

I spend far more time looking for information here than I do offering it, but this was today's project, and I hope it might be of use to someone else with a '96. Some of these details are things I really wish I would have known in advance, others are things which are out there to be found, but I could not find them all in one place. Other things may just be clarifications.

The 1996 Cherokee is a bit of an odd year out with regard to the fuel pump and regulator assembly. Prior years have a fuel supply line, a return line and a regulator on the fuel rail. Later years have a completely different tank and completely different pump/regulator assembly. '96 is all by itself.

Much of the information I came across said that a regulator for a '96 could not be obtained all by itself, or that it was not even a replaceable part. This was a bit disturbing, particularly since some of these sources cited the differences in fuel pressure for a '96 vs the prior years (a '96 should be 49 psi +/-5 psi), yet when I looked at parts offerings, the regulators I could find were listed as being correct for '91-'96. And then there is the question of whether or not some '96s had the regulator on the rail, and so would there be two different regulators? And was I not able to find the unique one I needed?

I couldn't find definitive answers, so, I tore into the job with the parts I could find. There's always learning the hard way.

Problem history: Vehicle was getting to be hard to start. After the first time it surprised me by not starting up right away I did some research and found out about the problem of a leaking check valve. The poor man's solution was to let the pump prime the system first. Not a problem. I have diesels. I am used to letting the system take its time getting ready. But then it got progressively worse. I would have to turn the key on and off multiple times before it would finally start. Sometimes I would get it to start and then it would die on me for want of fuel. I would have to go back to priming it all over again. Finally, it died entirely. Fortunately at home, but unfortunately with a half tank of gas.

Everything I have read says that it is better to drop the tank than to try this job with the tank still in the vehicle, but with a half tank I wasn't too keen on trying to drop it. I did attempt to set up a siphon, but I couldn't get a line through the filler neck and into the fuel. I tried disconnecting the line at the fuel filter and tried to get it to siphon, but no luck there either. At that point I decided I would try the job with the tank still in place.

With the fuel line removed and the pump harness unplugged it wasn't particularly difficult to remove the pump assembly. Fortunately the fuel level was low enough to not be up to the height of the access hole for the assembly. The only challenge was figuring out which way to turn the assembly to get past each hang-up it offered on the way out. I did not come across much in terms of pictures of this assembly. Here are some of my own pics for those who may want to see what this unit looks like (note: the modified regulator is not what you should find--this is another version of hack and tap).

I suspect that modified regulator was a previous owner's attempt to increase fuel pressure. It is entirely possible that they came up with the same quandary I did and concluded that the only regulator they could obtain was the earlier, lower pressure version. I have no idea how they would have gone about adjusting pressure on an inaccessible regulator. I don't even want to think about it.

I went with the only version of a regulator I could come up with, ordered from Morris 4x4. It is a Crown 53030001. Those numbers matched the hacked one I removed. This is what the correct fuel pressure regulator should be:

Note that flat rubber gasket on top--that is the old one. I did not receive a new one. The new regulator came with new O-rings, but not that gasket. On the other hand, that gasket should be a very easy one to make, and I think it does little more than serve as a spacer.

Break here--before I max out on the number of images I can put in a post.

 

[Anak]

Continuing...

The pump I ordered off ebay. It is a Bosch. It came with a couple different socks, or pre-filters. Here is the correct one for my application:

There's a little retaining clip on the bottom. I didn't initially find that part with the new pump. Instead I used a tool like a dentist's pick to carefully pry off the old one and transfer it to the new pump:

However, I did later find the part that was supposed to do that job. It just doesn't quite look the same:

The biggest challenge was trying to figure out what to do about the vacuum fitting on the top of the regulator. There is simply no place to connect it. After searching for answers I found a youtube video here: http://www.youtube.com/watch?v=lvnISRKGFxw

That video shows a pump assembly being pulled out and it shows the un-connected vacuum port. I am hoping that is indeed the way it is supposed to be. That is how I am now running mine. (Note: Don't follow the removal sequence shown in that video. You will note he gets a face full of gasoline. Much better to disconnect the hose at the filter first and drain as much of that fuel out as possible, then disconnect the hose from the pump/tank, then pull out the pump assembly.)

I should note that swapping out the regulator is a fairly simple matter. This is a plenty replaceable part by my standards. The regulator is held in place by a cap which is retained by four tabs. Careful prying with a pair of screwdrivers will release those tabs one at a time. The cap lifts out and the regulator then lifts out. Just be sure to check and make sure that both O-rings come out with the regulator. I had to go fish the smaller one out of its bore. I installed the new regulator with just a drop of oil rubbed on the new O-rings. That part of the job was easier than opening a retail blister pack.

I should also note that the new pump did not come with a new O-ring for the gas tank. I picked up one of those at Napa:

Beyond that, it was just a matter of carefully fitting everything back into the tank and making sure the new O-ring was propery set in its groove. I didn't have any trouble with it. We'll see if I think differently after I top off the tank, but I really do think it all went back together just fine. I don't think dropping the tank needs to be the preferred way to do this job.

I also took care of the fuel filter and fuel hoses while doing this. I don't know if I found erroneous information, or turned dyslexic, or if something is different about my particular setup, but the information I took with me to the parts store said I would need about 2' of 5/16" fuel line and 6" of 3/8" line. In my case those numbers needed to be the other way around. The outlet for the pump is 3/8", the inlet for the filter is 3/8", the outlet for the filter is 5/16" and the hard line going up to the fuel rail is 5/16". I had to go back to Napa to get a longer piece of 3/8" fuel injection rated fuel line.

That wasn't entirely a bad thing however. I was also able to find some replacement plastic straps for the fuel line and wiring harness. The originals were already broken before I got to them. I couldn't get exact replacements, but I am happy with what I found.

I also got some better clamps for the fuel line:

Previously things were held up by some old electrical wire. This looks much better:

I think I have hit max on images...one more post to finish this up...

 

[Anak]

One more shot of everything all together:

Note that the new filter has a ridge around the middle. I wasn't too pleased with that. The old one mounted better as it could be centered in the bracket. Here's a pic of the old and the new:

If someone knows a better part number for the old style I would appreciate it.

I did add some foam cushioning to the mounting bracket. It is simply an adhesive backed weatherstripping:

The last step was to fire it up and find out what my fuel pressure would be. It is supposed to be 49 psi, but this is the same regulator that is supposed to give about 10 psi less on the prior years. The only difference is the lack of a connection to the vacuum port.

It took a few turns of the key to get fuel up to the rail, but once I got it started this is what I got:

And this is what a '96 fuel rail looks like:

One line, no regulator.

For anyone who may care, build date on this particular XJ is 4/96.

In spite of some of the information I have seen, it appears the '96 fuel pump assembly is indeed serviceable.

I would love to hear if there are some details I have missed, or corroboration of what I have found. I will update if I learn something more in this process.

 

[Runnin'OnEmpty]

Super job Anak, and very informative to those of us that
own 96 XJs. Regarding the lip on the fuel filter, my
original OEM filter had the lip as did the replacement,
and it fit fine.

I see you replaced the screw type hose clamps with the
true F.I. clamps. Good job. That keeps stress off the
hose ends.

I would recommend using hose rated SAE 30R9 for the
soft lines, rather than the more commonly found 30R7.
Both are fuel injection hose, but the 30R9 is rated for
much higher pressure.

Great work on the pics.

 

[four_shot]

Maybe the lower rating is due to the regulator being set up for operation under vacuum?

and thanks for the pics, very helpful!!!

 

[Anak]

Thank you for the kind words.

I have been running this fuel pressure regulator for about a year now. It certainly seems to be working. I believe the presence of a vacuum line, or the absence thereof, is what creates the difference in pressure regulation that we have between the '96 and the earlier H.O. years.

I appreciate the additional info on fuel line types. From what I can tell SAE 30R7 is a non-fuel injection hose type.

From Gates:

Standard fuel and oil (SAE 30R7) hose is rated for low-pressure applications at 50 psi​

working pressure up to 3/8” size, and 35 psi for sizes over 3/8”. This general-purpose​

hose contains a light reinforcement, and the rubber materials can be any compound that​

is suitable for fuel, oil and vapors. However, Gates engineers warn that this hose is not​

suitable for use on any fuel injection system—even as a return line.

And:

Fuel injection (SAE 30R9) or MPI (multi-port injection) hose is reinforced to handle​

higher pressures up to 180 psi. It can be used on all injection systems that use hose​

clamps, but it should not be used to replace coupled assemblies on fuel injection​

systems.

I didn't know to inquire about SAE type, but I did get fuel injection hose, and it appears to be Gates brand. It was what the local Napa had on hand. I will try to pay attention to this detail next time I am dealing with fuel injection hose. Hopefully that won't be anytime soon.

Gates link if anybody wants to take a deeper look: http://www.gates.com/oreilly/tech_tips/PermeationResistantFuelLineHose.pdf

It appears the SAE 30R9 is also a good choice for alcohol and diesel.

 

[Runnin'OnEmpty]

That's good info on the SAE hose types. I mentioned
it because a counter person tried to sell me the 30R7
as being fuel injection hose. Luckily I knew the difference
between the R7 and R9 ratings and found some R9 that
was pre-packaged on the shelf. (The rating will be printed
on the side of the hose every few inches.)

As a side note, my 96 had the screw-type clamps on the
fuel filter and tank fitting from the factory. Guess those
newer type F.I. clamps hadn't been invented yet in 1996...?
Every fuel pump I've bought lately has now included the
F.I. clamps and the 30R9 hose.

 

[StoobyMcdooby]

Anak, I am going to do this in a few days time. I will follow up with results. Thanks for the great write up!

 

[Anak]

Please do post back your results.

I would be particularly interested in the part numbers to be found on the O.E. fuel pressure regulator that you take out.

Additionally, going through my original post and looking at the Gates hose specs there is a better choice of hose for the short bits inside the tank:

Finally, for submersible applications such as in-tank fuel pumps, only SAE 30R10 hose​

should be used. As gasoline comes in constant contact with the outside of an ordinary​

fuel line hose, it can swell and prematurely fail. And when the hose fails, the pump will​

fail.​

Specially engineered to be submersible, Gates Submersible Fuel Line Hose exceeds the​

SAE 30R10 rating and is capable of handling gasoline, alcohol-extended gasoline or​

diesel fuel in fully immersed, mobile, stationary and marine applications.

I don't know how hard it may be to find that particular type of hose, but it would be worth looking for. I doubt what I used was up to that spec. We'll see if I find out about it the hard way.

 

[four_shot]

Please do post back your results.

I would be particularly interested in the part numbers to be found on the O.E. fuel pressure regulator that you take out.

Additionally, going through my original post and looking at the Gates hose specs there is a better choice of hose for the short bits inside the tank:

I don't know how hard it may be to find that particular type of hose, but it would be worth looking for. I doubt what I used was up to that spec. We'll see if I find out about it the hard way.

I'm surprised the pump didn't include a new short section of hose for inside the tank. I know when I replace an in-tank pump @ work, the hose is included w/the new pump. hmmm must be a 96 thing...lol

 

[Anak]

Maybe the pump did come with that section.

I am horrible about remembering that sort of detail. I didn't take a picture of the package and what came with it, so there is no way I am going to recall whether I provided that bit of hose or if it came with the pump. When I did this job the fuel pressure regulator was my big concern. I will hold out hope that you are correct about the bits of hose coming with the pump.

 

[Runnin'OnEmpty]

All the pumps I've bought recently, for different vehicles,
have included the hose running from the pump to the
in-tank regulator. The hose running from the regulator
to the hard line is not included, and the included hose
isn't long enough to cut to make two. Therefore the top
hose isn't normally changed, but it's just as prone to
failure as the bottom hose.

As mentioned in another post, I recently changed a
Ford(cough) Ranger pump, and
noticed a tiny split in the top hose. After that, I always
keep a hose supply in the garage and change out all
the soft lines when doing a pump replacement...

 

[bugout]

Anak, AWESOME JOB! Great pictures and instruction! Better than ANY FSM I've ever thumbed through.

 

[Southwest Chuck]

Thanks for taking the time to post this for us '96ers ! I have yet to replace the OEM pump/regulator in mine, but being 18+ years old does bring the issue to the top of my mind.

 

[Anak]

Here is one person who has struck out on the attempt to service just the fuel pump and regulator. I don't know what difference there may be in the parts, but something does matter. The good news is that a complete '96 fuel pump assembly was able to be obtained.

This is the combination that did not work:

Sorry for the delayed response. Fuel pump Bosch 69544 and regulator BWD 23020. That is what the local Advance Auto had listed for a 96 so I took a chance to see if I could get the parts locally and not have to wait for parts by mail. So, I am out the cost of those parts, but now we know they did not work. My suspicion is the Bosch pump is fine, but the regulator is not. I would have ordered the correct regulator, but I got the confirmation email that the sending unit was shipping so just waited on it. So, Quadratec can get the full Carter fuel sending unit for anyone who needs one and is willing to wait for it. Only around $235 shipped too. Direct plug and play and everything worked as it should.

Entire thread if someone wants the context: http://www.naxja.org/forum/showthread.php?t=1118332

 

[gradon]

Yesterday I swapped in a 97+ plastic tank since the baffle/tray in my 96's tank was loose(also wanted to lose weight). I had already upgraded the pump to a 255lph Walbro, so that along with the sender is available if someone is looking for a working used 96 setup.

 

[Dragonslayer]

gradon - I had been thinking about swapping in a later model plastic tank into my '96, too,
but I didn't know how much work was needed to do this. Were there any special mods needed to do this? What were they? Thanks.

 

[Dragonslayer]

gradon - I had been thinking about swapping in a later model plastic tank into my '96, too,
but I didn't know how much work was needed to do this. Were there any special mods needed to do this? What were they? Thanks.

 

[gradon]

You need the two filler hoses from the 97+ XJ(smaller hose necks up at tank and bigger hose is smaller than 96's). You need a smaller hose from external fuel filter to fuel pump nipple/barb(I had 2' of 5/16" fuel hose left over from a $3 pack in AA's help aisle). You need to to move pins around on the 97+ pump harness to match the 96's wiring(I'll post them tomorrow) and pull 6" of the 96's harness closer to the tank(my interior is stripped, so was easy--it's under the passenger rear left seat's carpet).

 

[Anak]

Sounds like some good information. Count me as interested too.

I have given serious thought to a GenRight 30 gallon (or whatever it works out to be) tank. They list the tank as only being for 1997+, but I would think a '96 could be accomplished too. The details you ran into would probably be the same ones to come up with the GenRight.