OK,so I've learned so much over the past 6 months or so with my abused XJ one reason why after a month or so I joined.

Codes and lack of PO maint have gotten me to this point. It's running horribly at idle... getting about 12 mpg and just seemed not quite right. I recently pulled the valve cover and gasped and the caked build up.

I've got spring break and normally bike to work alot so.... I've decided with 252K on the clock, the ticking, missing, continous P0303, low compression on #3 that pulling the head seems the way to go.

Have a good shop here in the ATL that will do a direct swap for $325 or will take a couple of days to go completely thru my head for $250. Have read thru my Service Manual and have found a couple threads and read what others have done. Not my first rodeo but honestly...nothing mentions setting TDC or anything...basically keep the push rods in order. Pull it off, put it back together with the "new" parts.

IS IT REALLY THIS STRAIGHT FORWARD?

(It has taken me about 35 mins to get it down to popping the head bolts and yanking it off. )

Considering new lifters @ ~$5.00 each and new rockers pivots and bridges for $12 a cylinder. ( Or put mine thru a carb cleaner in a bucket bath ).

Plan to use Fel-Pro Head Gasket with new Head Bolts.

Have I horribly missed something?

 

Did you determine the cause of the low #3 compression?

 

Radi, honestly not for sure. The Jeep runs pretty good after 1K rpms. My thought was a possible weak spring. The springs rockers and valve train are pretty ugly looking but still puddle oil in the tops of the rockers. Due to this visual I am leaning to the head rework. Last week I had found a post regarding the tick possibly being a intake/vaccum leak. I've searched all over the engine for the vaccum leak and really thought that could be the cause of my issues but never found anything solid. Also with the same post was bad fuel mileage due to exhause leak or cracked manifold. I was REALLY hoping to find obvious signs on the intake/exhaust gasket but did not. The gasket does look like it was installed totally dry. I have always used a good coating of Copper Spray A Gasket on these gaskets on prior Jeep 6 cyl with great results. I am still even thinking about putting it back together after cleaning what I can up. Meaning cleaning both manifolds up good. New gasket. Cleaning all the rockers and pivots and push rods. I have been using Marvel Mystery Oil in place of 1/2 quart of oil for the past two oil changes trying to slowly clean up the engine. I also replaced both motor mounts and the transmission mount with the tear down thus far. The drivers side mount was shot. The passenger side look dry but not tore up like the driver's side. The transmission mount looked mostly in one piece but with some slight cracking. The only other area I'm not sure of the impact is the PCV system. The PCV looked like it had never been changed. I am having the valve cover itself vat cleaned at the local machine shop. Had also read that the "meter air" of this system needed to be truely functional and I doubt it was.
Thanks for helping with my double check. Trying not to use a 10lbs hammer on an 8oz problem.

 

OK...so yanked the head off today. Worst thing....check out the pictures in this Flickr photostream... You will see the reason I would like to take a baseball bat to the PO and their lack off prevent. maint. I will be spending ALOT of time cleaning out sludge. Part of me says just yank the damn short block on out and rebuild the damn thing.

http://www.flickr.com/photos/90926892@N04/

 

I went with a donor 4.0 if ur gonna do a full rebuild u would be just about as cheap to do a long block. I got my donor for free so made my decision easy.

 

Honestly at 252K miles and a history of bad maintenance, I'd rework the whole thing. These motors live a long time, but that one has been seriously neglected. Lord knows what the bottom end, cam, etc. looks like.
I'd hate to see you put $300 into the top end and have the bottom fail a week later. I suspect it'll be rings next, then bearings... it'll nickel and dime you. While it's not cheap, it is less costly to do it all at once.