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Putting an 0331 Head On A '96 XJ ... Nowhere For Temp Gauge Sensor?

seanof30306@yahoo.

NAXJA Forum User
Location
Tulsa, Ok
Cracked another head on my XJ. Head rebuilder on had an 0331 head, which he said was a direct replacement.

I know an 0331 is a downgrade, but this XJ is my daily driver, and I've got to get it running.

Guy doing the work just called and said there's no place for the temp gauge sensor.

Is there a fix?
 
The easy solution for the temp sensor would be to extend the wiring. But you may also have issues with the exhaust manifold.
 
The easy solution for the temp sensor would be to extend the wiring. But you may also have issues with the exhaust manifold.

I'm not understanding where the wiring would be extended to, and from where?

Apparently, 1996 was the last year the temperature gauge sensor was in the head, it moved to the thermostat housing, where the temp sensor already resides.

Great, I thought, I'll just get the later housing and move the sensor there.

Nope.

Same housing.

What I understand now is in '97 and later XJs, the gauge sensor was eliminated entirely, and the gauge reads off of the pcm, not the dedicated gauge sensor.
 
The exhaust ports and manifold are different in 2000 and later Jeeps.

You need to get a head from a 1999 or earlier, or you need to modify your exhaust.
 
The exhaust ports and manifold are different in 2000 and later Jeeps.

You need to get a head from a 1999 or earlier, or you need to modify your exhaust.

Thanks for the response.

I don't think the exhaust is going to be a problem. Years ago, my exhaust manifold cracked. I ended up buying a replacement Chinese exhaust manifold off of ebay; the one with the accordion-looking spots on #1 and #6.

I'm pretty sure it was for '91-01 XJs.

If I'm wrong, what exhaust manifiold mods would I need to make?
 
The easiest route is to add a hole to the thermostat housing. There's a nice flat spot that makes it easy.

Putting early model exhaust on an 0331 head is not a problem. Putting late model exhaust on a 7120 or 0630 is.
 
I'm not understanding where the wiring would be extended to, and from where?

Apparently, 1996 was the last year the temperature gauge sensor was in the head, it moved to the thermostat housing, where the temp sensor already resides.

Great, I thought, I'll just get the later housing and move the sensor there.

Nope.

Same housing.

What I understand now is in '97 and later XJs, the gauge sensor was eliminated entirely, and the gauge reads off of the pcm, not the dedicated gauge sensor.

But you would be extending "your" wiring, nothing would change but the length of the wire!
 
To your temp sensor in the new (thermostat housing) location.
 
Thanks for the response.

I don't think the exhaust is going to be a problem. Years ago, my exhaust manifold cracked. I ended up buying a replacement Chinese exhaust manifold off of ebay; the one with the accordion-looking spots on #1 and #6.

I'm pretty sure it was for '91-01 XJs.

If I'm wrong, what exhaust manifiold mods would I need to make?

The exhaust changed in 2000 with the introduction of new emissions. Some 2000 have federal emissions with two cast iron manifolds that go into a Y pipe. The rest of the 2000's and all 2001 have mini-cats.

You should expect to have exhaust leaks at the manifold or buy a 2000 and up manifold and fit it to your vehicle. Or buy a 1999 or lower head.
 
The exhaust changed in 2000 with the introduction of new emissions. Some 2000 have federal emissions with two cast iron manifolds that go into a Y pipe. The rest of the 2000's and all 2001 have mini-cats.

You should expect to have exhaust leaks at the manifold or buy a 2000 and up manifold and fit it to your vehicle. Or buy a 1999 or lower head.

I would add that everything on the exhaust is going to bolt up just fine, you'll notice it when you start it.
 
I know an 0331 is a downgrade

Check out 1bolt's post about half way down the page.

https://www.jeepstrokers.com/forum/viewtopic.php?t=1460

md21722, if he's putting this into one with a gauge sending unit, it's an early model. The early model exhaust works with a 0331 just fine, used the gasket to match the exhaust manifold. It's putting late model 0331 based exhaust on an early model 7120 or 0630 head that's the problem.

https://jeepexhaustadapter.com/
 
This is my CCH 0331 head that Russ did his magic on!
P1080516_zpsybaiiwn0.jpg
 
I needed to add, mines a 2000 but running a '98 header.
 
This is my CCH 0331 head that Russ did his magic on!
P1080516_zpsybaiiwn0.jpg

Don't you hate to cover that up? He did a 7120 for my stroker. I posted a bunch of pics on the jeep strokers forum. Hated to hide it under stock parts. However we have smog, and my smog guy was like "That sounds like a cam!?" me: "Do you see a cam?". Passes with flying colors.

Mark
 
I love looking at ported heads. I like engines with ported heads even better

Russ ported Edelbrock aluminum head
24405425561_3ed8faf6ca.jpg


Russ ported 7120 head
Exhaust port
43663020500_2cda765c5a.jpg
/

Intake port

38883742781_4205ee067d.jpg


1997 XJ 7120 Ported head and manifold
45429390582_82f0a87ac4.jpg


www.flickr.com/photos/lwade/sets/72157701143334781/
 
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