Well I found a small crack between 3 and 4 on the bottom and decided I'd still bring the head to the shop anyways. I'm sitting in the machine shop and the guy said the head is bent like a banana and looks like it had been cooked!!

At this point should I be concerned that the previous owner had driven it like this for 5-10k or more in regards to the condition of the lower engine components?

I might just sell the thing and buy a different XJ if this could've damaged the lower end. As you can probably tell from previous pics this thing is dirty as all hell and clearly hadn't been properly cared for (oil, cleaning, etc.) so it may be best to find a better cared for one..

Cool, can I ask what J&C is? Maybe a link to something?

$390 shipped isn't terrible if it's a non-0331

 

Ok. So the head is toast and you need a new one. With the head, gasket, bolts and hardware you're north of 600 bucks just there. If you do the water pump and related cooling components and other miscellaneous stuff it's another 200 bucks plus. So you'll have a minimum of 800 in this rig and you don't know how long the bottom end will last. Plus, you said it has rust.

You've already spent a bunch of bad money buying this heap. You need to decide if it's worth chasing it with good money now.

 

The water pump was done about 15-20k ago but I definitely see your point here. I've found a new casting version (aftermarket TUPY if you will) for $400 on eBay here:

http://www.ebay.com/itm/NEW-4-0-AMC-...EwAsPg&vxp=mtr

So I could get that plus head bolts and gasket which I was quoted would be another $120 and perhaps be all finished with $525 down the drain? I haven't touched the lifters yet, but could get a new set for $42 according to the shop if need be...

So at least $570 if I'd like to keep this and make it run right.


On the other hand:

I could potentially buy some crap used head or a remanufactured eBay head, cheaper gasket set, reuse headbolts and only be out $350, and then sell the thing running to someone who would just use it as a beater and invest in a different XJ.

Cheap rebuilt head:

http://www.ebay.com/itm/REBUILT-4-0-...FRU06u&vxp=mtr


Either way, I'll be on the lookout for local deals on a TUPY head. Is it alright to pull one from the junkyard, or are those likely wrecked too?

 

5-10K miles on a bad head/gasket is a recipe for disaster.
$266 for a rebuilt head isn't bad though.
How much did you pay for the jeep,and how about some pics of the body/interior.
You'll get some good advice then.

 

Quick update, I ended up going to three different junkyards and eventually finding a grand Cherokee from '03 that had front end damage with a. Good motor and TUPY head. Pulled that sucker off and had it machined at a local shop, put a new set of gaskets on, reused the old rockers and push rods and got new head bolts to throw it all together.

It runs pretty well, much better than before, but it's got a decently loud tick to it now. Felt very powerful driving around for the first 15 or so miles and now have a code for engine misfire at 4th cylinder and a TP sensor circuit low input. Replaced the TP sensor and still no better....

Could the tick be a bad lifter causing a 4th cylinder misfire? I didn't have the misfire before rebuilding the top end although there was a slight tick... And how do I fix a low sensor circuit input since I already replaced the actual throttle position sensor??

Progress is still progress though! Learned a lot pulling apart the junkyard engine and rebuilding my own. It was actually really fun since I had the time

 

Well **** I am probably in the same boat as your sons jeep now then.... Should've listened, was trying to stretch my budget. Seems like terrible timing though, I didn't have this 4th cylinder misfire before the head was replaced..

 

If it runs now, dont worry about the lifter too much (Personally it was a mistake not to replace them but ok.) Drive it. It will loosen up. Change the oil. Are you sure you're not hearing a bodacious exhaust leak from the infamous cracked manifold problem,? This one can really fool you into thinking you have a lifter. And have you double checked all the intake exhaust bolts?
Open the hood at night with it running and see if you have any wires sparkling.
I hate to think you have a valve hanging up.

 

Thanks for the reply. I'll definitely drive it around, change the oil and maybe add seafoam to try to work the lifter back.

I occasionally get a code for major EVAP leak, could that be an exhaust manifold crack? I know there's a small hole in my muffler, too. I torqued all bolts appropriately but I'll check them again tomorrow to see if they're shifted with heating and cooling.

And I just cranked up the engine and couldn't see any wires sparkling, just a dark engine bay with a loud tick and a disappointing misfire! ...

Edit: I'll do a compression test in the morning to rule out exhaust leak on the 4th cyl (I think that would make sense?)

 

Yes the compression test would make sense to rule out a sticky valve. I'm now leaning toward a misfire problem as the source of your noise. Do you have coil packs? Are they all connected correctly? Could the connectors to the injectors have gotten switched where they break out of the wire loom? The valve train noise could be a symptom of the misfire, and once you fix that the noise will go away. I assume the plugs are good. ? After a big job like that you may expect problems, take time and go through it again. I wouldn't drive it too much though until you sort it out.