My new XJ is a "Heinz 57"

Just acquired a 2000 XJ project with 133K miles, PO said the transmission was bad. After cleaning the gear position sensor, the transmission is no longer bad.

However, Murphy wasn't done with me yet. After a few minutes, the power fell off and the temp gauge went up. I coaxed it back home and investigated.... exhaust coming out of my radiator cap.

It was suggested to me that I was the newest member of the 0331 club, which has been a going concern for a few years.

I peeked around under the hood and did a few hasty visual checks to identify the engine - noticing 2-piece exhaust and DIS spark, and ultimately decided to order a new head from Clearwater rather than mess around with changing over to one of the older style heads.

The new head is on the way so I figured on getting started. Once I got the intake manifold out of the way, I noticed a blob of plastic melted onto the head, apparently from the plastic shroud for the injector wiring. A screwdriver easily removed it. This is where it gets freaky... under the melted plastic was a casting number.... 7120.

Fasced with this new information, I checked the rail the holds the coil packs to see how that assembly was mounted.... it wasn't. The whole thing was just poked onto the spark plugs and was not mounted to anything.

At this point, I am sort of relieved - a 7120 swap is what I had originally intended to do. I decided against it to avoid having to source a different exhaust and the possibility of ticking off the ECU.

Looking this gift horse in the mouth, and with the intake and exhaust out of the way, I see that the casting number on the engine block also indicates a 1991-1995 model.

Upon removal of the head, I discover a crack in the #1 cylinder head, about an inch long and a millimeter wide. No surprise there, was a large amount of exhaust in the cooling system.

------

Now the decision: I understand that the 1999-up engines had a different cam grind to match the smaller exhaust ports of the 0331 head. If I go ahead and use the new 0331 head, will I be leaving a wad of torque on the table? I am assuming the cam in this engine is also 1991-1995 vintage.

I have a 7120 head available, should I stay with that type given the block and cam?

Captain Obvious says: Your engine was replaced at some time in the past.

There was a late change to try and regain some torque that was lost to emissions compliance, the intake manifold change for instance. The HP didn't change, just the power curve if memory serves me right--and it doesn't always.

Here are some numbers:

Renix 87-90, 177 HP @ 4750 rpm; 220 ft lbs @ 4000 rpm.

HO 91-95, 190 HP @ 4750; 220 ft lbs @ 4000 rpm.

HO 96-01, 225 ft lbs @ 3000 rpm.

Those numbers are from "High Performance Jeep Cherokee Builder's Guide" by Eric Zappe.

I'm not 100% sure, but having an engine that is older than the body, may be a inspection failure as well. I know in Cali and NY it is at least. You may be forced into a new engine.

Altus, huh? My grandparents eloped there in the middle of the night (from Olton, TX) and got hitched.

Since it has ECU / injection / exhaust / sensors / DIS from the 2000 model I bet the question won't come up. It looked totally stock to me when I picked it up, but I wasn't at all educated in the subtle differences between the non-Renix models. I just noted that it had DIS so assumed (incorrectly) that it was all stock. When I discovered exhaust in the coolant, that _really_ made me assume that it was a 2000 model with the dreaded 0331 casting.

I sent an e-mail to Clearwater advising them of my mistake and will be returning the new head and eating the freight and restocking fees, etc. A buddy here in town has a 7120 head, will take it down to the machine shop and get it worked over with a 3-angle valve job, new seals, etc.

I'll post up some pics of the carnage later.

If I do get forced into a new engine to pass inspection, I foresee me taking it out to a gas station in BFE for all inspections. Otherwise, this XJ will be forced into a new career as a rock crawler. Wifey won't like that.

As far as I can tell, emissions inspections vary in Texas depending on your proximity to a major city, but in my area, if the damn thing has a horn, wipers and lights that actually turn on, you will likely pass. Some inspectors glance under the hood but I'm not absolutely sure what they are looking for. They did away with the headlamp aim requirement years ago. I actually thought that was one of the more useful parts of the test although you always had to pay the station a few bucks to aim your lights. At least there was a slightly better chance that you weren't going to be blinded every time you met a bubba in his giant pickup.

This has been mentioned before--year of the engine vs. legality for inspections. Too many darn states and not enough interest on my part to look into it thoroughly, but how would an inspection station know if you have the wrong engine installed--by year--if all of the correct year emissions equipment is installed, the engine is the correct size--a 4.0 is a 4.0--and the ENGINE number is not part of the VIN number?

If we have any emission station inspectors on the forum could you provide any details for your state or specific county/city if the standards differ there?

Replaced head (7120), thermostat, water pump, radiator, serp belt and spark plugs, so engine is happy as a clam. Took it to the A/C shop today since the A/C blows a choice of hot and hotter. After the A/C is done will take it for safety inspection, it has been expired for a year. The station I usually go to is not very forgiving with problems, hopefully they won't find anything bad to say about the rig.

Might I suggest a different inspection station might be a better choice? Just kidding. Good luck.

spctrbytz said:

Replaced head (7120), thermostat, water pump, radiator, serp belt and spark plugs, so engine is happy as a clam. Took it to the A/C shop today since the A/C blows a choice of hot and hotter. After the A/C is done will take it for safety inspection, it has been expired for a year. The station I usually go to is not very forgiving with problems, hopefully they won't find anything bad to say about the rig.

Click to expand...

If all of the emissions equipment are there...; then there shouldn't be anything to tip off the guy as long as NOx and CO are within spec.
One way to look at this would be; if this station can't find anything wrong then no one short of a knowledgable Jeep tech would find anything wrong either....

CharlesS said:

...there shouldn't be anything to tip off the guy as long as NOx and CO are within spec.

Click to expand...

No inspection here in Abilene checks emissions anyway, so won't have to dodge that particular bullet.

Haven't taken it to inspection yet, it is currently under the knife at the air conditioner repair shop... 105 degrees here and the power windows are inop... priorities!

CharlesS said:

If all of the emissions equipment are there...; then there shouldn't be anything to tip off the guy as long as NOx and CO are within spec.
One way to look at this would be; if this station can't find anything wrong then no one short of a knowledgable Jeep tech would find anything wrong either....

Click to expand...

X2.

There are no significant changes to the longblock from 91 till 99 (aside from 0630 vs 7120? I don't know head casting numbers well, is one of those RENIX and one OBD?) that I know of, aside from NVH stuff and possibly something for the newer intake manifold. Hell, if I was a little more motivated at the moment I'd check the parts catalogs for year splits. As long as your emissions equipment, vacuum lines, cat, O2 sensors etc are all in the appropriate locations and you pass emissions... you are golden.

spctrbytz said:

Haven't taken it to inspection yet, it is currently under the knife at the air conditioner repair shop... 105 degrees here and the power windows are inop... priorities!

Click to expand...

Power windows and A/C are inoperable too !!! OUCH.....

I have driven thru Big Spring and Odessa numerous times during the summer months; A/C is a must.....

If you need assistance troubleshoot the power windows; don't hesitate to post....

Charles

CharlesS said:

Power windows and A/C are inoperable too !!! OUCH.....

I have driven thru Big Spring and Odessa numerous times during the summer months; A/C is a must.....

If you need assistance troubleshoot the power windows; don't hesitate to post....

Charles

Click to expand...

Yep, I remember when the a/c went out in the Conestoga wagon, and then it happened again in the Model A! Those were rough times! :roflmao:

joe_peters said:

Yep, I remember when the a/c went out in the Conestoga wagon, and then it happened again in the Model A! Those were rough times! :roflmao:

Click to expand...

You probably remember when Moby Dick was a minnow!! :laugh: