I just bought a 2001 XJ today, haven't picked it up yet. It turns over, but won't start. The guy said the previous owner had overheated it and after that it didn't start back up. When it turns over, it turns over really slow, even with a good strong battery (the one the guy had on his XJ), almost like it's jumped timing. I know head gaskets and coil packs are great places to start because they're notorious for them. I won't be picking it up for a couple weeks, but I thought it'd be good to start getting some ideas bouncing around to start with. Thanks

 

If it was overheated, it very likely has a cracked cylinder head. The 00-01 from the factory came with the 0331 head, which has a casting defect between cylinders 3-4. That area often cracks upon even a single overheat.

You need to educate yourself about the 0331 head issue. Instead of rehashing it here, use the SEARCH function for threads on this forum. Also check out this thread.

http://www.jeepsunlimited.com/forums...d.php?t=391831

The hook with this cracked head is it leads to coolant in the oil, which leads to toasted engine bearings if not caught QUICKLY.

 

make sure your getting spark and good fuel pressure at the rail. it could even be a bad starter. i just recently got a new starter because mine was turning over so slow. also check your grounds. start simple then work your way up.

and there is a good chance it has a cracked head. which if so and the owner didn't drive it you would just need a new head. if they drove it you could have bearing wear.

 

^^Start here^^ If they cracked the head and it has been sitting for a while the internals of the engine could be covered with water and rust giving you the slow turn over. I wouldn't try starting it anymore until you can start ripping into it. You can cause a lot more damage if it isn't already completely crapped out.
Hope you didn't put out to much money for it. Because it really does sound like your in for a complete rebuild.
Good luck and let us know the out come.

 

^^true when i bought my 2000 it had a cracked head and had sat for 3 years without running. by the time i got it it was so seized up it wouldn't turn over with water on top the cylinders when i started taking it apart.

 

Alright, thanks guys! I will definitely check that out first thing, I did pull the dipstick on the motor, the oil doesn't have any water in it from what I saw. I only paid $900 for it, so even if the motor is gone & I have to fork out another $900, that's still a 2001 XJ for just $1800. I'll check back once I get it & have a chance to really tear into it. One question, since the 00-01 motors had that weak head, would it be possible to put an older head on it and hook all the coil packs to it? Just curious

 

Read the thread to which I provided a link to in Post #2.

It discusses engine options in that thread.

 

Yeah I read that right after I posted haha, thanks ya'll! Once I get started I'll keep you posted

 

Well, If you only paid $900 and everything else is in good shape such as body and interior. Throwing a grand at it for another engine you still got a pretty good deal.

 

That was my train of thought, it's solid as a rock & the interior is freaking amazing, power everything, couple of dings on the body but nothing too noticeable at all

 

So I FINALLY picked it up today and started to look around at what the problem might be. There is no water in the oil, at all, so I doubt it's the head or head gasket, but it still turns over slowly, and it fires once or twice but won't start. I'm thinking that it could've jumped timing because it fires and has good fuel pressure, or I also think it could just be the starter dragging, any ideas?

 

Get a rubber mallet or hammer and hit the starter a couple of times and then try starting. If it looks like it has more power starting you have corrosion in the starter that is creating some resistance. Sometimes when you have a problem with the starter, hitting it will cause it to work.

Also put a compression tester on the cylinders and see what readings you get. It may show all is well or if you have a problem.