Exhaust manifold, fuel injecter quick-connect o-ring

Hi All,

Yes, another exhaust manifold. Replaced mine about 50K ago, but the old girl sounds like she has blew it again. Must say that I couldn't visually identify any cracks, but I guess at 200K she deserves a little attention again, and I can't think of anything else that would sound like this.

So last time I didn't replace the fuel quick-connect o-rings, simply because I didn't know about those when I started the job, so just plugged them back on and prayed. Got lucky then, no leaks. This time, since I know, I feel I should plan ahead a little. So two questions,

1) Do I need to replace them at all? Haynes and FSM seem to think so, but what is the general consensus here (based on experience), yes or no?

2) Where do I get them? Dealer only? Any aftermarket places carry them?

Oh, yeah I'm talking about an l6, 4.0, 1992, limited edition, with 200K miles.

Thanks for any input!

NAPA or autozone will have the o-ring set, about $8. lube em up good with vaseline to avoid any tears on re-install. it can still tear, so make sure theres no leaks. i also like to clean out the cups of the fuel rail with scotchbrite, fuel crust forms here overtime

yours can be soft or rock hard, it depends. i like having new ones on hand. its typically a special order part so i keep an extra set in the shop.

how are your motor/transmission mounts? might explain the chronic cracked exhaust mani's?

You might also try checking to see if maybe the bolts have simply worked loose first..before pulling everything apart.

Great guys, thanks for the input. I will get o-rings this week and get an extra set for backup.

Yes, both points are well taken, motor mounts could be bad, will check, and I will check torque on manifold bolts. For torqing down those bolts I suspect that I will still have to tear some things apart though? Anyway, will give it a try before ordering a new manifold. By the way, I don't usually would suspect the exhaust manifold right away, but when I had the problem the first time it took me some time to figure out that the manifold was cracked (I suspected loose bolts or broken gaskets) and after some reading it was my understanding that they crack 'all the time'. Maybe I took that too literally.

Thanks again guys!

dutchjeep said:

Great guys, thanks for the input. I will get o-rings this week and get an extra set for backup.

Yes, both points are well taken, motor mounts could be bad, will check, and I will check torque on manifold bolts. For torqing down those bolts I suspect that I will still have to tear some things apart though? Anyway, will give it a try before ordering a new manifold. By the way, I don't usually would suspect the exhaust manifold right away, but when I had the problem the first time it took me some time to figure out that the manifold was cracked (I suspected loose bolts or broken gaskets) and after some reading it was my understanding that they crack 'all the time'. Maybe I took that too literally.

Thanks again guys!

Click to expand...

Pull the airbox out and you'll have enough room (with a couple of extensions and a wobble on the end of them of course!)

Ok, checked motor mounts (ok) and torqued down all bolts. Was hopeful since the connecting bolts from manifold to exhaust pipe were not too tight, but to no avail. When torquing the bolts I did see a crack along one of the welds on the manifold. Not the one where they all come together (that's where it cracked last time), but where the rear header pipes come together. So it looks like it's manifold time again. Guess I will then also finally put that Borgeson steering shaft in that has been waiting for this for a while.

So I called Napa about the o-rings (for the fuel injector to fuel line connectors), but they said they couldn't get those. Called the local dealer, and they want $15 for 2 o-rings, so that would $45??!! Wow, these rings must be made out of some pretty special stuff! Does that price sounds like about right, or did they look at the wrong part? Anyway, I don't think I have much of a choice in any case. $45 is still way better than an engine compartment on fire.

Any recommendations on where to get a good exhaust manifold (if there is such a thing for the XJ)? I think I got the last one from autopartswarehouse, but I'm not really sure.

Thanks for thinking along guys!

Are you looking for the o rings that actualy go on the injector? or the disconects on the ends of the rail? if its the O rings on the injector... Check with Napa Again When I did my 88 a few years ago thats where I got mine. I do seem to remember them coming in a strange number though.
http://www.naxja.org/forum/showthread.php?t=914093
If it is the disconects, then be prepared to drop at least 20 a piece on either dealer or aftermarket, and more likely than not shipped.

EDIT... If you do a little searching here there was a guy that replaced all of his fuel clips with newer AN fittings and braided line. it wasnt more than a couple of months ago and I think it only cost 60 bucks or so? If I had to do it again thats the route I would go.

yeah... that sounds waaay high. i think i remember paying $8 for the entire set?

think i bought em at autozone (their site shows em, as out of stock, but ask in a local shop). i really think napa is only as good as the guy behind the counter. ive had em tell me stuff was only available at the dealer as an excuse for them to not look harder...

i run AN fuel lines, love em, but they only delete the fuel quick disconnect o-rings, still need all the injector stuff.

Yeah I know. I think I found them a little cheaper (not by much though) on www.wholesalemopar.com, but still discussing with them whether they are the right item. I'll try a few other napa's too, good idea.

In the meanwhile I ordered a new manifold from APN and will just go ahead and replace it, even if I can't find the o-rings. Want the o-rings as a backup in case a leak does develop after re-connecting fuel line (will check carefully when testing).

I was going to suggest the Dorman manifold. They changed it within the last couple of years to include 2 flex joints. I went through two APN's..the first got taken out when my drivers side motor mount seperated, and the second had a casting flaw right where the flanges for runners 1-3 and 4-6 join which prevented it from sealing to the head properly. With the new motor mounts and the dorman manifold, all is well.

GP Sorensen #800-9220 Is the part number for the o ring kit at autozone I beleive. The part numbers in my thread may be off? I just checked them against my parts catalog, but realized its an 88-90 catalog so the factory numbers may have changed. Also remembered that the O rings that I got, and most aftermarket are going to be all the same color, not 6 brown-6 black like the factory manual says.

Ok, took out the old exhaust manifold and now had a closer look at the motor mount on that side, in particular on the back side that I couldn't see very well before. And yes, it turns out to be broken. So you were right XCM, that probably explains why I lost another manifold. Thanks for pointing it out! I wouldn't have looked so carefully if you hadn't mentioned it. I'll get new motor mounts tomorrow morning. Does anyone know of a good writeup on replacing these? Thanks again!

I don't remove the intake manifold from the vehicle when I have changed manifolds. Nor do I disconnect the wiring or fuel lines. You can snake the exhaust manifold out and it saves a bit of time.

for the motor mounts, what i do is put a wood block on a floor jack, loosen up the thru-bolt, and the 1 bolt, and 1 nut on one side at a time, then lift the floor jack a lil bit to lift the motor mount off the frame rail, then replace. you may have to man handle the motor to get it to sit back down right, but generally it's pretty easy. also, on my 90, the oil filter is in the way on the passenger side, i cant remember if i had to pull the oil filter neck, or just the oil filter... if you do the neck, might wanna swap out the o-rings as well.

WHEN YOU PUT THE BOLT BACK, put it facing the other way, that way you dont have to pull the oil filter, should you have to do this again.

Just a quick follow-up. I replaced the exhaust manifold, and when I pulled it off, the motor mount on the driver side turned out to be toast. I didn't check carefully enough when I looked before. Was actually kind of happy with that since at least the problem of the cracking exhaust headers seems solved. So I replaced the motor mounts also. Yes the oil filter adapter needs to come off, but other than that was a pretty easy job. The headers turned out cracked at several places and that explains why it had gotten pretty loud lately.

For removing the intake manifold I disconnected the quick connects, but the injectors can stay in place. I guess you could probably leave the fuel lines attached to the rail, but I like to get the manifold out of the way, so that wouldn't work well for me. After all was done I re-attached the quick connects very carefully and never replaced the o-rings as they seem fine (no leaks).

Anyway, operation is done. Engine runs silky smooth again, and all seems well. The headers must have been cracked longer than I realized since I don't recall the XJ being this quiet en smooth.

Thanks for all the input guys!