my door sticker on my jeep says it was made 3-99

so do i have the 0630 cylinder head?

im assuming i dont have to worry about the late 1999 with the 0330 head right?

i have a cap and rotor...with plug wires...not the coil pack ignition


any info would be great

 

Your safe. Lots of info on it already on the net.

 

I would think a 3/99 build date would be a late build '99 XJ.....just ahead of the '00 XJ that probably started being built in late summer '99. My guess is '99 model XJs were at the dealers starting +/-Sept. of '98. That's usually when the new models r 1st introduced........late the previous calender year. Don't know how late '99 XJs could have gotten a 0331 head or if any '99 XJs got a 0331 head.

 

Good info man. IIRC it was XJ's produced in late '99 that had the 0331 head. It would make sense, too, that the ones built in late 99 were the new models for 2000...

 

I have yet to see ANY concrete evidence of a 99 with an 0331 head. They have the 0630. If you have a distributor and not a coil rail, you have the 0630 head.

But don't take my word for it. It's very easy to verify. On the drivers side, halfway back on the head is the casting number.

You will need to clean that area thoroughly with a rag or use degreaser if very dirty. Then use a GOOD light and you will be able to read the head casting number.

If yours is a 99, that head casting will say 0630.

 

Just because a Cherokee was built in '99 doesn't mean it's a '99. Cherokees built mid to late 1999 were actually 2000 models.

 

<--- Build date is 2/99 and I have the 630

 

Huh???

 

I have a 99 xj, as far as I know I do not have the dreaded 0331 head.

 

Great! Yall have me worried now. My XJ is built in 11-99 and has the coil rails. Now what is the issues with the late 99s?

 

That's a 2000 model year XJ then, the head with coil rails is known as 0331 which is infamous for a casting defect between cylinders 3 and 4. It is prone to cracking when overheated. Many threads on here about this... be extremely vigilant about cooling system maintenance and check the level of coolant frequently. If it just starts disappearing and you don't see any leaks this is cause for concern.

This is aside from the added fun with the two pre-cats in the exhaust manifold boiling the fuel

 

Mines got a build year of 98 but it's a 99. Just giving some input.

 

If any of you are worried then pull the valve cover off and look for the number, either 630 or 0331. You're valve cover is probably leaking anyways... lol

 

Broken Nose.....Please check the head CASTING NUMBER midway back on the head as I explained in post #5 for absolute verification of the head. Will only take a couple of minutes and you do NOT have to remove your valve cover. The number is on the lip of the head about midway on the outside edge.

Please report your findings back here!

 

Can it be replaced with a 630 without any issues with the fit.