Hey guys, so my 2001 XJ had multiple misfires and symptoms of a blown head gasket. Sure enough, the MLS gasket blew between 5 and 6

So since now the manifolds are removed and the head is off, what else should I check for and maybe clean or replace since I'm this deep into the engine anyways?

For example, how do I check the cylinder walls for problems, or check that the piston rings aren't stuck / skirts destroyed?

Also, my block and all of the intake and exhaust ports are completely filled with carbon buildup, the PO abused this poor thing and burned oil / ran low coolant for thousands of miles. Any advice on removing that buildup without getting it into the engine too much would be much appreciated.






blew between 5 and 6



lots of crap in there... I wanna clean it but not get it into the engine on accident





could barely see the head bolts when I removed the valve cover...



Before and after me cleaning the rockers



are the white ones considered burnt valves?

 

man thats a mess in there.. looks like the PO never changed the oil...

at the very least i'd send the head out for a rebuild.. freshen that thing up.. not sure how to clean all that oil sludge though. have to be careful not to clog the oil pick up screen with all that crap..

 

I take it your replacing that head with a new one right? The old one was the 0331 I'm guessing, its a shame that you didn't try to run some engine cleaner through it before tear down to get rid of some of that crud and flush the cooling system. But it is what it is now you haven't said what the mileage is on the engine that would help us a little with suggestions.

 

I may order a remanufactured head here:

http://www.ebay.com/itm/REBUILT-4-0-AMC-JEEP-CHEROKEE-LAREDO-0331-CYLINDER-HEAD-/271941391704?hash=item3f50f85558
Originally was going to take my head into a local guy who would clean, machine, and magnaflux it for ~$445 total, but the reman'd head is cheaper.... I wanted to go the local route since it's one day turnaround and then I'd have his advice to fall back on as support, but the head is so gunked up that the reman'd one is tempting.

As crazy as it sounds, I did run engine cleaner through it, and power washed the whole bay before disassembly. It's just that full of crap!! Dropped the ball on flushing the coolant out, yes...

The engine has 225k on it and has the 0331 head. Was running very rough, w/ an engine light for misfire on 5 and 6 for 5k miles or more. The jeep is new to me and I don't have contact with the previous owner any longer.

Good news was the rockers were all solid, push rods looked clean and straight, and the bearings in the bridges between rockers were straight and not destroyed.

Thanks guys!



EDIT:

Also, just to give an idea of the extent of crap all over the place, here's a pic of the side of the engine block after soaking in degreaser for 20 min and power washing:

 

i'd probably go with a tupy head http://www.ebay.com/itm/JEEP-TUPY-4-...jrpRLQ&vxp=mtr


or the clearwater head..

 

I would but that's a bit pricey for me right now. Honestly might just reassemble this after a valve job and sell to get a different XJ... Might be cheaper for me considering the rust and crap all over this one.

$445 includes gasket set and head bolts from the local shop, so if I got a TUPY it'd be $685 plus tax once I bought the gaskets and head bolts separately


I'd be willing to spend the extra $$ if I knew the rest of the engine was gonna be fine in the long run though... How can I check for other lower end issues that might warrant looking at a different XJ? I realistically don't have the money or space to pull the engine out for a rebuild for now and want a reliable DD

 

When you want a reliable DD, $200 extra on a job like that to have a new, no issue head is cheap insurance. You may want to check on a Clearwater head. I think they are less than $500. Don't cheap out at this stage.

 

Worse case scenario is sell the head when it blows. I wouldn't put a nickel into a 0331 head.

 

Gotcha, I agree with that statement, but in reality here I don't have the money and just need to pass emissions and be back on the road as cheaply as possible. If my current head isn't warped (I'll have it checked at the shop on Monday) I'm gonna grind and seat valves myself and put it back on with new gaskets. If it's cracked I'll be forced to buy a new one and then would get a non-0331 but I might just sell the thing at that point and buy a less problematic XJ

So anything else I should check up on while the head is off?

 

Pop on the Ebay head and gasket then see where things stand. If your oil pressure is good, the engine has power and no excessive blowby or oil contamination after changing the head, I'd leave the bottom end alone for now.
The best way to clean that crap out of the block is to pull it and hot tank it. If you aren't going to do that, then resist the urge to chisel away at it...just leave it be. You don't want chunks floating around in there.
Once the engine is reassembled, run Rotella + MMO in there and it'll eventually clean things up.

 

Wow. In regards to your question about the white exhaust valves - I have that condition and posts here and elsewhere consider that normal.

 

Toss lifters in there while its apart too. wont forgive yourself if you dont. White does not mean burnt.

 

Freeze plugs in the block, easier to do with it worn down like you have it.
Lifters, I regret not doing this to my sons, It has a lifter peck in it now.
On that head you have been given some good advice, I found a 04 head and had it redone at an engine shop.

 

I am in the same boat as you, but with a cracked head. I replaced the gaskets (obviously) for everything, got a new thermostat, housing, coolant hoses, water pump. etc while I was in there. Figured if I have it apart might as well replace what I can.

 

I bought a aftermarket head from J&C two weeks ago for my daughters 01 for $390 shipped. Still wrapping up on the install because I am taking my time on installation but, I was quicker at getting the head off and sent back so I wouldn't be hit with the core charge of $150.