rogiii

I'm changing theleaking o-rings on my dads cherokee 88 4.0 he brought the o-rings from auto zone they are all brown in colour. When I took the injectors out I noticed the upper o-rings were Black and the lower were brown does this matter? Is there a differance in size? Because when I pressurized the system I'm having aproblem with the upper rings on all six injectors leaking the lower rins or all dry I followed the manuel rut motor oil on upper & lower they all poped into place nice . Help Would be Greatly appreciated THANKS

Abovetimberline

They are the same,I have used both in upper or lower,I have removed them from other xjs for spares and found them all black,some brown,it did not make any difference when I installed them.

bleedheavymetal

Same here. I replaced all my injectors because they started leaking. I used the autozone o-rings and i have not had any leaks. That was about a year ago. Although I did break the quick connect for the fuel line and had to chop it and hose clamp it back on. A little oil on the rings also helps them go on easier.

rogiii

thanks for the response!!! A little frustrated I went back out to go back over my work and verify the leaking. Upon closer examination the leaking isn't coming from the upper o-rings I just assumed thates were they were leaking from rather it's coming from between the metal injector body and where the upper plastic part of the injector com toghether is there a fix for that? does that area come apart where there is an o-ring there that can be replaced? or is it time to get new injectors? If so what kind of injectors should I get? I'm new to this fourm and Jeeps but lst night I was reading on the fourm where guys were pulling injectors out of fords with the four hole spray pattern. I have a pick a part 1 mile down there a few cherokee's one is a 89 pretty simular with a 4.0 should I try that . Problem is I'm trying to do this on the cheep thats why I'm considering that please way in!!!

bleedheavymetal

That is exactly why I replaced mine. I am pretty sure the only thing you can do is replace them. Even if there is some way to patch them it definitely wouldn't last long. When I replaced mine I had 2 leaking and replaced them. Immediately after I replaced them another 2 started leaking and I replaced them. Then the last 2 started leaking so I ended up replacing all of them. $50 bucks a pop at autozone, be sure to use your rewards card to rack up points, lol.

bleedheavymetal

oh, and on the ford parts. I haven't heard of that. I myself wouldn't replace injectors with junkyard parts. I would rather pick new ones and not have the problem back shortly down the line. But that is just my opinion.

5-90

1) The dimensions are the same. Older kits would come with six "high-temperature" o-rings and seven "low-temperature" (the odd one was for the FPR at the front of the rail,) but they've started throwing thirteen HT o-rings in the kit instead to keep it simple (at least, for the dealership kits. Aftermarket probably similar, except for the FPR o-ring.)

2) You've got an 88 - that's RENIX. Are you sure they're leaking from the O-rings, and not from the crimped seal on the injector body? Check to see if they're original - OEM RENIX injectors have a metal lower body crimped to a plastic upper body, and that crimped seal tends to leak. The only fix is replacement - you can use Ford/Chevvy SB fuel injectors (19-20#/hr delivery, most OEM units) or some later 242ci Jeep units to replace them. Make sure they have the same electrical connector - they're Bosch units.

If the injectors are leaking from the body seal, do not drive the vehicle until you have replaced the injectors! A leaking injector will drip fuel right onto the exhaust header - and engine bay fires suck!

If you want sets for a decent price, you can check out FiveO Motorsports (www.fiveomotorsports.com, I believe) and order from them. They stock "pulls" that are reconditioned and matched - so you're getting a "like-new used" injector vice something you'd pull at the boneyard. They're checked to hold pressure and for delivery rates, so you'll be fine there. And, they list kits for the 242ci Jeep engines, so you're good there as well!

Abovetimberline

88 and 89 xj 4.0s are the same,if you can get the injectors that is what I would do if you are on a budget,I would also take the orings for spares,I have a baggie full of them,I would not use injectors from anything else other than an xj from 87-90,I put injectors from an 91 in my 89 thinking it would have more power,it cost me fuel mileage,they are bigger injectors. I use many parts from the pki-n-pul because I have to,and I also carry spares of everything.

rogiii

5-90 I must have RENIX because the leaking is exactly how you discribed it between the injector body andwere the plastic uper body meet. thanks everybody for your response. while I was out in the garage I lifted the front on jack stands my DAD was complanig of a woble coming from the steering I checked and started pulling & tugging everthing looks tight except the left front wheel king pins or big yoke look good lug nuts tight the axel nut with cotter pin good it's coming frome behind the axel nut that little axel that conects to to the long axel were there is a u-joint the little axel and I can see the rotor move together I doublel checked the axel nut I was expecting to find that loose but looks good. Any Ideas Im using this Haynes manuel doesn't show much.