2000-2001 Cherokee head issue

[ArmyGuy45]

So I have heard that the 2000-01 Cherokee heads can crack when they over heat. Is there a fix to this or do you just swap heads?

[slvmart]

Cylinder Head Casting # 0331 (stamped on Driver's Side at top, middle at valve cover edge. Used from 2000-2001
NOTE: "0331" used a mounting boss for the Coil Pack. Switching to an earlier Head ("0630") will require special brackets to Valve Cover to support Coil Pack.


In 2002/2003, Jeep switched to a different casting ("TUPY") from Brazil. Supposed to be stronger, better than "0331" '99-'04 Grand Cherokees's use "0331".


"TUPY" casting is visible through Oil Fill Cap, looking straight down at Head


SYMPTOM:
Unexplained coolant loss.
Oil pressure may go down after starting, warming up.
No heat; Low coolant.
Poor idle; Misfire. Check Engine Light.


Try this : http://www.cherokeeforum.com/f2/00-01-xj-cracked-cylinder-head-overview-118922/

[ArmyGuy45]

Cylinder Head Casting # 0331 (stamped on Driver's Side at top, middle at valve cover edge. Used from 2000-2001
NOTE: "0331" used a mounting boss for the Coil Pack. Switching to an earlier Head ("0630") will require special brackets to Valve Cover to support Coil Pack.


In 2002/2003, Jeep switched to a different casting ("TUPY") from Brazil. Supposed to be stronger, better than "0331" '99-'04 Grand Cherokees's use "0331".


"TUPY" casting is visible through Oil Fill Cap, looking straight down at Head


SYMPTOM:
Unexplained coolant loss.
Oil pressure may go down after starting, warming up.
No heat; Low coolant.
Poor idle; Misfire. Check Engine Light.

Try this : http://www.cherokeeforum.com/f2/00-01-xj-cracked-cylinder-head-overview-118922/

Thanks for the link. I followed the directions and I have 63769D near the rear of my valve cover and dead in the middle I have 53020323. Neither one of these are the numbers described in the link. So where is the number at?:bang:

[msmoorenburg]

So I have heard that the 2000-01 Cherokee heads can crack when they over heat. Is there a fix to this or do you just swap heads?

Swap heads

[4.3LXJ]

Once they crack, then swap the head

[ArmyGuy45]

Do I have one of those weaker heads?

[4.3LXJ]

Yes you do. If you don't have to pass smog, you can do a little work and put the 96 and up HO heads on and pick up a few ponies.

[ArmyGuy45]

Yes you do. If you don't have to pass smog, you can do a little work and put the 96 and up HO heads on and pick up a few ponies.

I do, sadly. It wont pass with the new head? There is no fix? They cant add more metal to it?

[4.3LXJ]

I do believe there is an updated head with a little more metal in it. But as for adding metal to cast iron, difficult to impossible. But I did see an engine once that was a Model B Ford with the inner water jacket bored out and another block cast around it. It had 5.25" pistons, a couple of 2" pipes for an intake manifold. Still a flat head, but held a local track record in a Valiant for many years.

[Mudderoy]

Yes you do. If you don't have to pass smog, you can do a little work and put the 96 and up HO heads on and pick up a few ponies.

How would they know? The heads look the same.

[4.3LXJ]

How would they know? The heads look the same.

It would pass the visual, however the changes to the intake and head were to pass the more stringent smog regs. I would assume that they wouldn't pass with the older head. I think that at some point, they knew they would not be able to make the 4.0 pass as requirements were upped. I think that is the main reason they went to the 3.8L

[Mudderoy]

It would pass the visual, however the changes to the intake and head were to pass the more stringent smog regs. I would assume that they wouldn't pass with the older head. I think that at some point, they knew they would not be able to make the 4.0 pass as requirements were upped. I think that is the main reason they went to the 3.8L

Oh wow so what you are saying is eventually a perfectly legal vehicle that was 25 or 30 years old would just eventually not be able to meet the tighter and tighter restrictions.

My God we need to get rid of these people in our Government.

[Sneedle Vision]

Oh wow so what you are saying is eventually a perfectly legal vehicle that was 25 or 30 years old would just eventually not be able to meet the tighter and tighter restrictions.

My God we need to get rid of these people in our Government.

Is it necessarily that? Or could it be that as time goes by and technology changes that they're looking to cut out shortcuts? Just saying.

But I do agree that changes are due.

[4.3LXJ]

Oh wow so what you are saying is eventually a perfectly legal vehicle that was 25 or 30 years old would just eventually not be able to meet the tighter and tighter restrictions.

My God we need to get rid of these people in our Government.

Not really. At least here in smog land, the emission standards you have to meet are for the year of the engine. So in my case, since I have converted the engine I have to meet the emission standards for a 94 engine even though it is in an 86 Jeep. In his case, he will have to pass 00 emissions standards, so I am doubtful that he can use the earlier head. So far, I exceed those standards by a fair amount. I plan on putting on 99/00 Vortec heads in the future which will improve that more and hopefully make up for the cam that will go with them. You can go forward with tech and parts, buy not backward in the smog world

[XJ Wheeler]

Hey Steve, is it true in "smog land" when doing an engine swap the donor engine has to be newer than the vehicle its going into? Something i heard a while back and was wondering if its true.

[4.3LXJ]

Here it has to be the same year or newer. If newer, it has to include all emissions equipment including the stock air box and transmission if different. When you get into OBDII that would also include the gas tank.

[XJ Wheeler]

Here it has to be the same year or newer. If newer, it has to include all emissions equipment including the stock air box and transmission if different. When you get into OBDII that would also include the gas tank.

That's nice... and ridiculous.

[Carves]

So I have heard that the 2000-01 Cherokee heads can crack when they over heat. Is there a fix to this or do you just swap heads?


FWIW ... the easiest fix is not to overheat it.

... which means ensuring the cooling system - is matched/upgraded to the driving tasking, you intend doing.

Thats not to say the head will always be OK ... but its probably the best way to extend its service life.

[ArmyGuy45]

FWIW ... the easiest fix is not to overheat it.

... which means ensuring the cooling system - is matched/upgraded to the driving tasking, you intend doing.

Thats not to say the head will always be OK ... but its probably the best way to extend its service life.

Ya I can agree to this, but this is something you cant limp home on if it cracks on you. I will look for a donor head when I upgrade my exhaust.

[xjrev10]

Ya I can agree to this, but this is something you cant limp home on if it cracks on you. I will look for a donor head when I upgrade my exhaust.

O yes you can. I've heard of dudes driving their jeeps with a known cracked head, adding coolant as needed till funds where available for a reman...Guy at work just had to replace his in a 01 WJ, and stated above is what he did!! Ha!

[jeepguy702]

hi Guys....I'm working on a 99 GC Laredo
I bought it knowing I was going to rebuild the motor. I thought it was just like a JC 4.0, and internally it may well be, but the block casting is totally different. Do you know what block number you are working on? Mine is 53010327AB.
I have a 258 crank and rods for a stroker motor. This will be my second build this year.
When I took the head off the Laredo the number 2 piston was exploded gone, another problem that Im reading is common to this model motor. I'm looking for info from anyone that knows of anyone rebuilding this motor.
thanks

[Mudderoy]

hi Guys....I'm working on a 99 GC Laredo
I bought it knowing I was going to rebuild the motor. I thought it was just like a JC 4.0, and internally it may well be, but the block casting is totally different. Do you know what block number you are working on? Mine is 53010327AB.
I have a 258 crank and rods for a stroker motor. This will be my second build this year.
When I took the head off the Laredo the number 2 piston was exploded gone, another problem that Im reading is common to this model motor. I'm looking for info from anyone that knows of anyone rebuilding this motor.
thanks

Is the block any good? I would expect that cylinder to be heavily damaged if the piston failed.

[ArmyGuy45]

So when switching out heads. All you need is a donor head right? would everything switch over from the 01 head? Or is it better to have a fully built head from that year and just swap them out?

[4.3LXJ]

Matt, if you are thinking of the HO head you need a complete head. There is a little porting to be done to match the 01 intake to the HO, but very simple to do with a die grinder and carbide burr.

[ArmyGuy45]

Matt, if you are thinking of the HO head you need a complete head. There is a little porting to be done to match the 01 intake to the HO, but very simple to do with a die grinder and carbide burr.

Man I want a pre 00 head and a standard Cherokee. Maybe I should just sell my 01 and get like a 97 that is a standard. Might be cheaper!!!

[4.3LXJ]

Not really. Do some cooling system upgrades and then you will have insurance against the cracking. They only go when it overheats.

[ArmyGuy45]

Not really. Do some cooling system upgrades and then you will have insurance against the cracking. They only go when it overheats.

So bigger radiator? Electronic fan system plus the what is on it now?

[nhra13]

As it turns out I inherited a 01 XJ with a cracked head already. I have had a misfire for like two months and assumed it was the rings or something, maybe even the coil bridge. Today I had a coolant boilover and decided to pull the valve cover. What do you know... green coolant right between the two cylinders I get misfire codes on. Looks like I'm buying a new head soon.
But I have been driving on it for like two months.

[4.3LXJ]

Yeah, you can get away with driving on them for awhile. But eventually you have to address it

[ArmyGuy45]

No issues with the head yet. I plan to beef up the cooling system, seems cheaper than swapping heads.

[XJ Wheeler]

As it turns out I inherited a 01 XJ with a cracked head already. I have had a misfire for like two months and assumed it was the rings or something, maybe even the coil bridge. Today I had a coolant boilover and decided to pull the valve cover. What do you know... green coolant right between the two cylinders I get misfire codes on. Looks like I'm buying a new head soon.
But I have been driving on it for like two months.

Could just be the gasket. Never know.

[nhra13]

deleted

[nhra13]

So it seems I have confirmed the worst. Right in between the two cylinders that have misfire codes.
http://i1068.photobucket.com/albums/u446/Newandy24/photo-4_zps8f43e5d9.jpg