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New XJ, New Problems (Head Gasket)

Xj_idget

NAXJA Forum User
Location
Cincinnati
Hi All -

I am hoping someone can help me with a decision I need to make with my "new" 2000 XJ limited (4.0/AW4/129K miles). I live in Cincy, purchased from Florida and drove it about 1000 miles back to Cincy. About 1/2 way home, the check engine light came on, but...blah, blah, blah...long story-short: driving around town it overheated and turns out there is likely a blown head gasket involved.

My mechanic (I know I won't have time to tackle a head gasket myself at present) says that it will take about $1400 for a head gasket replacement (including zyglo'ing/refreshing the cylinder head). HOWEVER, he does not recommend it on engines with over 100-110K miles or so, because according to him there is a likelihood of increased oil consumption afterwards.

I would not have thought replacing a head gasket (assuming it's done right) would cause oil usage (whether through excess blowby, or whatever) unless a cylinder wall has been scored or something. Here are my questions:

1. Does it makes sense to expect increased oil consumption after a head gasket change on a 4.0

2. I'm sure many have changed 4.0 head gaskets. Has anyone experienced more blow-by or other oil loss after a head gasket replacement?

Bottomline, I don't want to spend $1400 just to come out with a compromised engine. If I'm getting into that territory, I might consider another engine instead.

Any and all help much appreciated, this community is awesome!

~ Steve
 
Last edited:
this an '00 it very likely the head has cracked causing the gasket to fail because the castings suck for that year

you can get one from clear water cylinder head or Alabama cylinder head for about ~$400 shipped and return slip for the core with an improved cast
 
Thanks guys, I appreciate the cyl head info, but for me the critical questions are:

1. is there any reason to expect increased oil consumption after a head gasket replacement on engines with greater than 100K miles?

2. has anyone replaced a head gasket and then seen an increase in oil blowby or other increased consumption?

Thanks ~ Steve
 
is it OK to replace with another 0331 though?
you can do the tuppy ones from the TJs but even still its like $150 for a junkyard one plus you need to get it machined and magnaflux it for another $100+ and no guarantee that wont be cracked cracked as well plus you be using old valves and seals or get a new cast with new valves and everything and not have to revisit a issue with the head
 
Thanks guys, I appreciate the cyl head info, but for me the critical questions are:

1. is there any reason to expect increased oil consumption after a head gasket replacement on engines with greater than 100K miles?

2. has anyone replaced a head gasket and then seen an increase in oil blowby or other increased consumption?

Thanks ~ Steve

The fellas wre just trying to point out that your particular year of 4.0 is prone to head gasket and or head cracking problems due to casting problems.

So, if one were to pull this head off due to such problems you might upgrade (with little or no price increase from $1400) to the new and improved design.

"Search" the site for all your needs.
 
!. Why would there be more oil consumption ?

2 Find a new mechanic.

The cylinder head seals the combustion chambers and the water passages, there is no reason to say that oil consumption would increase. If you drove an excessive number of miles with a failed head gasket or cracked 0331 head, you would have coolant mixed with your oil, and the possibility of cylinder damage or bearing damage is possible. Bearing damage would be evidenced by low oil pressure after the cylinder head/head gasket replacement.


Find a 2002+ TUPY 3001 head from a Jeep 4.0L. Have it tested and refurbished, and then install it. Inspect for cylinder and bearing damage.
 
Thanks for all the input. I think I caught the problem before much oil/water mixing occurred, so I will check into an appropriate replacement head and go from there. I've not seen the term TUPY before, but I'll do a search and see.

Thanks again ~ Steve
 
When Jeep became aware of the 0331 head cracking issue they re-designed the 4.0L head and added the letters TUPY to the casting.

The improved TUPY 0331 head is much stronger and less prone cracking.

.
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!. Why would there be more oil consumption ?

2 Find a new mechanic.

This. Run far away from that mechanic. If he thinks replacing a head gasket leads to an increase in oil consumption than he is doing something wrong.
 
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