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Replacement Cylinder Head Question

pajeepman

NAXJA Forum User
Anybody have any experience with aftermarket 4.0 heads. I need one for my 2000 XJ. I won't used a reconditoned one because of the poor history of them, unless it was from an '04-06 engine. Hesco is WAY TOO expensive. I was looking at clearwater cylinder heads or Alabama cylinder heads.
ANY experience with either or another company.
 
If you have studied the threads, you know that you can also use an older head. '98 or earlier. I got one for $50 for my 2000. People have posted results for clearwater and alabama. As a matter of fact, I see a thread below about Alabama heads.
 
Reports from the field are good from ACH - I'm not sure if they're new or inspected/remanned, tho.

You can use 2002-2007 WJ/WK/TJ heads (#0331) as a direct replacement. If you go with an earlier head, you may have a bit more work - the #0630 heads (1996-2000) have the same size exhaust port exits, but the #7120 (1991-1995) are larger and will require a block-off plate so the exhaust won't leak at the primaries. Information on that can be found here, I think someone was making "#0630 to #7120" adapter kits that should work with the #0331 heads as well.

The only true "aftermarket" head I can confirm as new production is the aluminum job being sold by HESCO and Patriot Performance - which is probably the same head from both shops (and I'd like to know who's casting them and how they got the idea - we were bashing this around on the "Strokers" egroup back around 2001, then I took the info gathered to Russ Flagle at Indy Cylinder Heads...)
 
I talked to he guys at ACH at length about their heads before I ordered one for my '01. I ran mine pretty hard out to Moab and back shortly after install an had no issues. Direct bolt on and a good quality piece for the money.
 
D'oh, Jon they didn't make the 4.0L past '06 and they didn't use them in the WK. :)

Ah - so "cancelled for 2007," not "cancelled after 2007," then. Got it.

I'd always thought that production life of the thing was 21 years - 1987-2007. I guess it was an even twenty. Pity - it deserved far more. Look how long the SBChevvy, Ford Windsor, and Chrysler LA-block were around!
 
You can use 2002-2007 WJ/WK/TJ heads (#0331) as a direct replacement. If you go with an earlier head, you may have a bit more work - the #0630 heads (1996-2000) have the same size exhaust port exits, but the #7120 (1991-1995) are larger and will require a block-off plate so the exhaust won't leak at the primaries. Information on that can be found here, I think someone was making "#0630 to #7120" adapter kits that should work with the #0331 heads as well.

You are close, but IIRC, the 0630 (96-99 1/2?) also have the larger exhaust ports. A block off plate or just using a 91-98 header will work to adapt exhaust. I plan to change to an older header and adapt to the exhaust with the 0630 replacement head.
 
You are close, but IIRC, the 0630 (96-99 1/2?) also have the larger exhaust ports. A block off plate or just using a 91-98 header will work to adapt exhaust. I plan to change to an older header and adapt to the exhaust with the 0630 replacement head.

Pthargh. I have got to finish my head collection. Anyone have a warped/cracked 7120 or 0331 (or two) lying about anywhere near San Jose, CA?
 
winterbeater is right about the 0630 being near identical to the 7120. I'm willing to give you the 00 cast 0331 I pulled off the 01. It has at least 3 valves that don't seal. I don't see the common crack on top b/t 3 and 4, but there are hair-line cracks that emanate from 3 of the coolant port triangles, so I could see the possibility of a HG not being able to stop coolant from getting in the cylinder or gas-air mixture in the coolant. I'm opposite coast in MD. . .
Oh yeah, I bought a J&W thicker cast 0331 head for the 01 for $369 shipped(no core charge--they don't recon, 2 yr warranty). Odessa also had one for $375 w/ a 1 yr warranty, and Clearwater had them for $400 w/ a 5 yr warranty.
 
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Ah - so "cancelled for 2007," not "cancelled after 2007," then. Got it.

I'd always thought that production life of the thing was 21 years - 1987-2007. I guess it was an even twenty. Pity - it deserved far more. Look how long the SBChevvy, Ford Windsor, and Chrysler LA-block were around!

I wish they had modernized it like GM's 4.2L inline six or even better. I think the guys at Chrysler didn't like it because it wasn't their own motor, pity in was the best motor Jeep had.
 
Oh yeah, I bought a J&W thicker cast 0331 head for the 01 for $369 shipped(no core charge--they don't recon, 2 yr warranty). Odessa also had one for $375 w/ a 1 yr warranty, and Clearwater had them for $400 w/ a 5 yr warranty.

I couldn't find J&W, did you mean J&C($369)?
Oddessa($369) is the same place as Clearwater($425)(Oddessa is the ebay company) I asked the guy what the difference was and he said they are the same head, just the CCH one has a 5 yr warranty vs 2yrs from Oddessa.
Alabama uses all new parts, the other places use old valves and springs.

Which would you choose?
 
Alabama uses all new parts, the other places use old valves and springs.

Which would you choose?

I would definitely go all new, it's only $100 more for a new re-enforced head with all new valves, springs, seals, retainers and clips. Come on now that's not even really worth debating is it? But it's your money and ultimately your decision.
 
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I would definitely go all new, it's only $100 more for a new re-enforced head with all new valves, springs, seals, retainers and clips. Come on now that's not even really worth debating is it? But it's your money and ultimately your decision.

It's actually $150 more than the the head from CCH with the 2 year warranty. I do like the idea of all new parts. My friend that works a machine shop said they use used parts all the time. I just gotta figure out how much I want to spend, it's gonna be another $100 for gaskets and head bolts and misc stuff.
 
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