There are two "filters" on your ZJ, a strainer sock inside the tank, and a filter/regulator assembly on top of the pump. Yes, you would need to drop the tank to get at either of them, but only the filter/regulator is available separately from the pump, as far as I know. The replacement filter/regulator is half the price a new Bosch pump (includes new filter), so if you're hell-bent on replacing it I'd recommend just replacing the entire pump if you're going to drop the tank anyway.

 

^ agree, and don't buy a cheap fuel filter/regulator in the 'can' on top of the pump module or you'll be sorry. Just too many problems with them and fuel pressure will be all 'over the board'. The SMP filter/regulator alone is $76 on Rockauto and I wouldn't install it to begin with. Plus don't think you want to drop the tank multiple times.

The best price on the new Bosch 67649 fuel pump model with filter/regulator and a new tank seal for your 97 5.2 is through Rockauto at $160. Bosch is OE and Mopar just relabels them while often selling them for 2x the price.

http://www.rockauto.com/en/moreinfo.php?pk=978065&cc=1182237&jsn=397

At checkout you can enter in discount code 5573649049747010 in the "How did you hear about us?" box for 5% off which will cover most the shipping costs.

Just curious if you've checked your fuel pressure at the rail to make sure it's the fuel filter, regulator, and/or pump causing your problems? Spec is 49psi +/- 5psi and pressure should not drop below 24psi after 10-20 minutes or the check valve on pump outlet could be bad. Good luck.

 

Out of curiosity, why not just replace the fuel pump motor itself? More so if check valve and such is working as intended.

Edit: Im a little confused... There is a regulator/filter that sits atop the tank, right? Then there is a separate fuel pump, of course, with a strainer on the bottom, correct?

So why do you keep saying just get it over with and replace the pump with a bosch unit? Does the new bosch pump come with the regulator on it?

Edit #2: Ive attached a page from the 98 parts manual.. I assume it comes with the fuel filter.... Very odd design really...

 

As I already mentioned this Bosch module does come with the new filter/regulator; "new Bosch 67649 fuel pump model with filter/regulator and a new tank seal for your 97 5.2", in addition to a new tank seal. The new filter/regulator is also shown in the Bosch module link I posted.

And if you dropped the tank to replace just the fuel pump, and perhaps strainer, would you not replace the filter/regulator at the same time? I've seen the cut-away view of these filters/regulators in the 'can' for the 97-98. The filter is round paper folded like a bellows around the inside of the can. You can bet after 20 years the filter material doesn't flow like new and the reason most change out their fuel filter more than the life of their ZJ.

I also talked to a Bosch rep extensively about their 97-98 fuel pump module. In addition to the check valve on the pump outlet the regulator diaphragm also functions as a check valve in helping to keep fuel in the lines for short periods after shut-down.

If you bought a new Bosch fuel pump alone, and a new filter/regulator you don't even know is going to work, you'd have as much money invested in this as the whole new module.

Maybe you're comfortable in having to drop the tank multiple times but it sounds like the OP is new to this. And I for one found dropping the tank to replace the pump module on my 96 4.0 a royal pain and would like to get it over with in buying a new Bosch module.

I have nothing to gain in telling members to buy the whole module and replace it with a Bosch. Just trying to help members out in finding the best deals from different vendors.

Also note I asked the OP about testing first so his fuel pressure is within spec and the check valve is holding pressure as it should.

Odd design indeed and more of a p***-poor design in having to drop the tank to replace the filter/regulator if that is the problem. Again, I'd replace the whole module for as much work it is to drop the tank and after all it is 20 years old.

I've never seen a new Bosch module not come with a new tank seal but the nylon locking ring is not included.

I hope this explanation points out I don't hap-haphazardly run around on this forum telling member to buy unneeded parts or more than they actually need. Plus better to be safe than sorry.

PS. the price of these new Bosch pump modules for the 97-98 was a little easier to swallow when they were $120 just 2-3 years ago but unfortunately the price has gone up to $160.

 

yes a new unit will be complete with filter/regulator, pump, gauge sending unit, strainer sock, gasket and lock ring. just hook up your fuel line and electrical and you are done. to replace the pump you need to take the whole unit apart to get to it.

 

yes a new unit will be complete with filter/regulator, pump, gauge sending unit, strainer sock, gasket and lock ring.

Don't rely on it coming with a new gasket and lock ring. As the illustration in the Mopar catalog indicates, the gasket and ring are separate items to the pump assembly. And some people who've replaced their pump have said that they had to buy a new ring after they damaged their existing one trying to get it released - the new pump didn't come with one.

 

Ohh I wasn't insinuating that you hap-haphazardly do anything, I was just confused. Ive never dropped a tank on a 97-98 but I have my 94, so I wasn't sure how it was setup. I always imagined the filter just being situated above the tank so that you couldn't get to it, I didn't know it sat right on top of the pump like that.

 

Poor choice of words on my part and now realize that wasn't what you were insinuating. Know it adds to some confusion how the filter/regulator is attached to the top of the pump module. At least the Jeep rocket scientists saw the errors in their design in having to drop the tank to change the filter/regulator out. They moved the filter/regulator into a half-normal 'can' housing in front of the tank on the WJ's so you could get to it w/o dropping the tank.

 

So after looking today and doing some research I found out my zj has a fuel filter inside of its gas tank. Being 20 years old and in such an inconvenient place, it's probably never been replaced.

I've heard I need to drop the tank to get to it but what do I do when I get to it? Replace it like I would if it wasn't in the tank? Would removing the tank be like removing a fake rock off of the pipes on the side of my house?
As in will it be fixed into the jeep or into the tank?

If it's fixed into the jeep I assume I don't have to replace the fuel tank and vise versa if it's not. I appreciate all the advice

You must drop the tank, or cut an access hole in the floor. (Drop the tank.)

The fuel pump module mounts into the top center of the tank. In the bottom of the module there are 2 filters (socks/strainers/meshes). There is an "internal" one connected to the bottom of the pump itself, and then out on the bottom of the module housing there is another one. These are available separately. These 2 obviously filter the fuel being sucked into the pump.

On top of the pump module, outside of the tank, there is the metal canister filter/regulator. This filters fuel coming out of the pump. It is replaceable without removing the pump module from the tank. It is held on by a metal strap and plenty of friction on its O-rings. Careful use of prybars will likely be required.

You can get away with spending less than $100 if you have time to mail order the in-tank strainers, and disassemble the pump module. The strainers are a couple of dollars on RockAuto, but ~$30 at a parts store. The filter/regulator is what kills you . . . ~$80 for a decent American brand (i.e., GP Sorensen). (DO NOT buy one from Herko!!!!)

So if you absolutely must keep the spending to a minimum, you can go this route. Otherwise, listen to Uniblurb and buy the whole new Bosch module.

strainers on Rock:
http://www.rockauto.com/en/moreinfo.php?pk=1112760&cc=1182226&jsn=380

filter/regulator on Rock:
http://www.rockauto.com/en/moreinfo.php?pk=1319645&cc=1182226&jsn=386

OK, I was wrong. Strainers at AutoZone are $9.99 for the same Delphi as the Rock link. p/n BFS0112. O'Reilly's was near $30 a few years ago.

WOW! the GP Sorensen filter/regulator is $113.99 now (p/n 800-430).

EDIT: more to this story
Dropping the tank is not that bad. You don't want to have much gas in it. The most aggravating part to me was getting the stupid pump wiring connector plug undone. IIRC, it is one of those with the little slider tab you have to get to release, then pull apart a grimy, stuck plug. (Something not easy to see and get to up under there. Use plenty of light.)

You'll want to clean out the tank while it is out and empty. I siphoned all the gas out and used carb cleaner + rags. The pump module hole is large enough you can get your arm in, unless you're a body builder. Some early ones had faulty linings which come lose over time (the yellow ones, IIRC). There was a recall I think, so it likely was fixed.

The entire new pump is really a "no-brainer", because as mentioned above, with the tank removed, you'll want to clean it out, so you'll remove the module anyway. There's little point in changing the regulator/filter (the outlet filter) unless you change the strainers too (the inlet filters), so that would mean disassembling the module. I mean, its not difficult, but you're not saving much money for the extra hassle.

Yeah, "much" is a relative term. I've been in the situation many times where $5 was "much".

 

Some good info RedRiver and Rockauto used to carry 2-3 filter/regulators for the 97-98 but phased out selling them when they became $100+.

I have a pretty good memory and know why you said to avoid the Herko filter/regulator altogether when your fuel pressure ended up in the mid-50's.

But as mentioned in one of my above posts I remember seeing a cut-away view of the filter regulator. That would be you and real good photo of the filter/regulator below with the top cut off!

http://www.jeepforum.com/forum/f13/fuel-pressure-fluctuating-wildly-leaking-injector-bad-regulator-something-else-2813538/index2.html#post28631201

If you live in the salt/rust belt it makes the tank more difficult to drop. The 'J' bolts on the front of my tank straps were so rusted I had to use a wire wheel on the threads. And after soaking with rust cutter for a while I still had to loosen the nuts just a little going back/forth while cleaning the rust off with a small wire brush clogging the nut threads. I had a pair of vice-grips clamped above the threads to hold the bolts so I didn't rip the slots out of the unibody. Luckily you only have to have the nuts loosened about half way on the threads then can lift the bolt head up out of the slots. I turned the straps completely sideways and removed them from up behind the bumper where there's only slots.

Then the hose clamps on the tank hoses were so rusted they were seized too. And it didn't help the clamps screw/hex head was on top assembled that way from the factory. I removed the back of the driver's side rear wheel well and removed the clamps/hoses from the fuel neck & vent tube. Then I pulled the tank out with hoses still attached to the tank through the oval frame hole.

It helps at the beginning in doing it by yourself to have a square piece of plywood under the plastic tank cut so it fits between the straps with floor jack underneath.

My 96 had the TSB issued for the fuel pump overheating and failing. Since I had fine black residue in the tank I washed it out with dawn dish soap, hot water and a rag. Then rinsed it out good and let it sun dry before installing.

The internal baffle in the tank where the filler tube hose attaches makes it a little difficult to siphon gas out along with dumping water out.

Luckily I didn't have the tank skid plate and was able to work around my trailer hitch w/o taking it off. Only wanted to do this job once.

 

Wild that the filter is so small. The filter on my 94 is a good sized fuel filter and it was BLACK when I cut it open. From what I remember, I know my dad changed the filter at least once from 94 till ~2013 or so. Its possible he changed it again, but I dont recall. I changed it in 2013 and thats when I cut it open. That fuel pump has no sort of strainer/sock though so the filter is the only thing it has.

It was quite horrible trying to drop my tank by myself. The hardest part for me was dealing with the fill/vent tubes. My tank was about half full though, fun times.

 

Yeah jeepjeepster, that filter does look pretty darn small. That according looking paper element reminds me the bottom of rotten mushrooms growing in the woods here.

That 'diaphragm' in the bottom/left of the photo look more like a metal or plastic disk with a rubber o-ring on it. The purpose of it is to open/close for spec pressure with any excess fuel going back into the tank hence no need for a return fuel line. Plus it's supposed to close down when the fuel pump is shut down to keep the lines full of fuel for a while. I can see where that rubber o-ring may become hard or brittle from age/heat like many rubber o-rings.

My 96 fuel pump was still working half-way and luckily I was able to pump most the fuel out of the tank into gas cans before dropping it.

I also had a heck of a time getting those rubber hoses off the filler neck and vent pipe. Even with the rear wheel well removed I had to spray rust cutter on the metal and let it try to seep down where they meet the metal. Had to stick a small screwdriver down in there since they did not want to turn with channel locks and was about ready to rip the hoses. Believe many don't even mess with removing the hoses on the filler neck but I couldn't remove them from the tank due to seized clamps.

My 96 fuel pump module did have a screen/filter in the very bottom of the module as can be seen below. Some may refer to this as a 'sock' because of the shape but it didn't look like the larger ones I've seen in some modules.