1998CherokeeXJ

I'm pretty sure my head gasket is goin on my cherokee, it's got a 4.0 with 158,000 miles on it. Is there anything else I should replace or upgrade while I'm in there? This is the first time I've ever tore apart this motor or any for that matter.

Bustedback

Why do you think you need a head gasket?

Fred/N0AZZ

This is not what you should consider as a "First Time Project" either as knowing exactly if its the problem for one.

Then do you have all the proper tools and knowledge to do this job. You will need machine work to the head while it is off and usually a valve job.

XJwonders

Fred, on the contrary. I think it's perfect timing for him to do it. That way he can learn about his XJ. If he's motivated to do so, he can do anything.

And doing a head job on 4.0 is really easy compared to other engines.

southsidecatac

Holy crap! You're really suggesting that someone who's never torn into a motor should go for a cylinder head removal? Uh, no. Even doctors practice on cadavers before they are allowed to cut open live patients. That kind of advice will likely turn that XJ DOA.

1998CherokeeXJ

I've helped do head gaskets on numerous other vehicles before, but why do I need the head machined and a valve job just to do the head gasket? Or is it somthing that if should consider doing?

XJwonders

I know a few guys who did just that and it sparked enough interest that they went and became ASE mechanics.

And I did the exact same thing myself.

JeepMN

The only way you're gonna learn is to try it. Don't listen to the naysayers. Just read read read, and then read some more and just go for it.

Literally though, read these forums. It has helped me personally so much in just general mechanics of a vehicle.

Good luck

Turbo X_J

How many miles or hours on this engine, what's the compression numbers? Chances are it's really tired, having the head mating surface cleaned up and renewing the valves while the head is off are just part of it. Plus having the head checked over before the machine work will tell you if you need a new head.

1998CherokeeXJ

I'm not sure of the compression but the engine has 158,000 miles on it

Turbo X_J

Lets start at the beginning, why do you suspect the head gasket has failed?

southsidecatac

Ok dude. You're up! Talk the guy through all of the diagnostic procedures to troubleshoot his problem. Then you can give him the list of tools and parts he will need to begin the repair. Then you can tell him where to get the tools and parts. Then you can provide step by step procedures for tearing the head off of his jeep. Then you can advise him of how to go about checking the head and getting it machined. Then the reassembly process. Don't forget that some intermediate mechanic tricks need to be divulged such as frozen/broken bolt extractions and how to prep close tolerance parts for reassembly. Perhaps the best post yet is asking the dude WHY he thinks the head gasket is "going".

Bustedback

Same thing I asked but never got an answer. 158k on a pre 2000-01 4.0 is pretty low, not very common for it to have a failed head gasket unless it was abused.

southsidecatac

OP must be doing something else. Like drinking beer. Cheers!

Parsnip

I did a head gasket as my first job in the driveway...and now I'm doing motor swaps and tranny rebuilds...just my 2¢