I just got myself a '98 XJ, last night, with 205,000 miles for $500! But, I believe it is in desperate need of a new radiator and tstat, so I am in the process of that fix but I think I have a worse problem. When I bought the XJ I drove it home (about 10-15 miles from purchase place) and when I got home there was a lot of smoke/steam from the passenger side of the radiator? Hoping this is caused by what I am already fixing but I started to hear after about 10 minutes of engine running a light knocking sound? I changed the oil, oil filter and air filter last night immediately and took her for a ride! Everything was running fine until we turned around to head home and the knocking came back. We stopped at a stop sign about 1 mile from home and she DIED! Engine would try and turn over but failed to until the battery was done! I'm hoping this "new" problem can be fixed with a new battery and alternator? And also is the knocking something terribly wrong in the engine? Sorry this is so long but I had a lot to say.....thanks for any replies/help and if I missed anything or if you need more info I will supply it!

 

I picked up my 98 last week, my 6th XJ. Anyways knocking is generally a bad sign. On the bright side, for 500 bucks if the rest of Jeep is in good shape its still not a bad deal even if you have to replace the engine. You might not get many replies as without being there its hard to diagnose an issue.

 

I also dont think a battery and alternator are in order to fix the "died at a stop issue" if you really think its one of those, take it to your nearest parts store when you get the battery charged and have them run a check on them but I dont think thats your issue.

 

Probably shouldn't have taken out for another ride if, you know, it was overheating like that. Also, knocking is usually a really, really, bad sign (somewhere up there with fire and brimstone raining from the sky, the seas turning red as blood, plagues of locusts, ect).

How's the oil look now, milkshaky? Is there oil floating on top of the coolant in the radiator?

Honestly it could be a lot of things, but from the information given my gut is telling me that a starter or alternator is not going to fix your issue. I think the first thing you need to do, after verifying that the oil and water didn't mix, is a compression test.

 

Did it have oil pressure?
The first knock being hot could've been because the oil was HOT and thin, but now it sounds like you might have an oil pump out.
Reasons:
It died, then knocked again, then it was hard to turn over like the engine was seizing up.
But on the bright side you can find an engine or another trashed jeep for the engine.
Good Luck with it.
I paid $500 for an 87 with 3/4 of the engine parts gone. So your still not to bad if your handy with a toolbox.

 

A great many jeep six cylinder motors have piston slap and it doesn't hurt them a bit. It could also be loose torque converter bolts. NBD there either. I doubt it is an engine knock. Serious engine knocks don't come and go. If it is something that fresh oil hides, it is pretty mild. Like the guy noted above, maybe the oil "thins" with heat and then you notice the noise. If that's the case, it ain't much of a knock. Finally, even if it DOES knock...who cares? Let it knock. Just don't run off on a cross country trip expecting it to go 6000 miles. Enjoy the jeep. For $500, you can't lose. Geez, you're in California - no rust, etc. You could short block that motor and not lose a dime.

 

Thanks everyone for all the replies! To go further with my battery replacement reasoning was because there was corrosion like crazy! The radiator has holes in the front?! But ad far as the knock I appreciate everyones responses and I'll certainly take them all into consideration! I have a pick-n-pull JY like 10 miles from home so I can get some cheap replacements!

 

The JY has a bunch of Cherokees but they are years ranging from 87 - 95, are parts interchangeable on my 98? I hope so because they are sooo cheap! Thanks again everyone!

 

Up to a point, 91 and newer yes, 87-90? Some parts will be, some won't. As long as it's a HO 4.0, though, most parts are interchangable. Things like sensors, wiring, and the ECU are more year specific.

For example, say you bought a '93 engine for your '98. You'd unbolt all the accessories and sensors from the '98 and bolt them to the '93.

 

Any year 4.0 short block will work in your 98. Use a H.O. head though.

 

I'll make ya feel better...I paid 5995 for a spotless 01 with new tires, mag wheels, and beautiful sparkling steel blue color. I have spent ~$1000 on a new A\C system, a front end part, stereo, etc. I'm 62 years old and this is the coolest, most fun vehicle I have ever owned. I had no buyers remorse, and have to fight my wife to see who gets to drive it. Fix er up, you wont be sorry.

Jack
Another proud and happy owner

 

That's pretty good deal imo. Post some pics when you get a chance

 

As far as the HO Heads go, will be able to tell if the 95 Cherokees Heads are the same? Is it easy to tell?

Jack,
Thanks for the support, I will have to admit that my wife said I shouldn't get this XJ but I insisted and now I've got a bit of buyers remorse! Right nkw I plan to fix 'er up and get her driving like new but it starting to look like a daunting task! :/ I feel like I'm in over my head right now but I might be able to dig out! Haha

Thanks a lot everyone!
- Billy