Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here XJ (84-01)
All OEM related XJ specific tech. Examples, no start, general maintenance or anything that's stock.

99 xj 4.0 radiator issues

Thread Tools
 
Search this Thread
 
Old 02-17-2013, 09:22 AM
  #16  
Newbie
Thread Starter
 
persnickety's Avatar
 
Join Date: Aug 2012
Location: Central Illinois
Posts: 9
Likes: 0
Received 0 Likes on 0 Posts
Year: 1999
Model: Cherokee
Engine: 4.0l
Default

I haven't been able to get to the shop yet. The same situation has happened twice more. The shop I was recommended was booked up on the days I could part with the jeep so I've had to wait and try to limp it along. It'll be dropped off tuesday morning and hopefully it'll end with a cheap resolution. I'll post results when things are figured out.
Old 02-17-2013, 09:48 AM
  #17  
Member
 
Bob98Classic's Avatar
 
Join Date: Dec 2012
Posts: 200
Likes: 0
Received 2 Likes on 2 Posts
Model: Cherokee
Default

Originally Posted by persnickety
Driving home this morning coolant spewed from I think the sprung cap valve. The temp gauge never read higher than 220, which is a tiny bit hotter than usual, but not extreme. After the spew the temp read about 230 until I got home. I couldn't look at it too much until tonight.

Started up the jeep to let it warm up. Waited 10 minutes, temp gauge didn't budge. I figured I mistimed it and headed out. Within a minute or so the temp ran up to about 230 and I turned on the heater to cold air. I got home, turned it off and I can hear wet air leaking from somewhere. The top radiator hose is soft.

I'm assuming there's an air pocket in there. Right? So I'll try burping.
Anything else I should check for?
What made the valve go?
I need to get to and from work, 15 miles each way at highway speeds, through tuesday.

It had a dexcool mud problem when I bought it used, so I've had the radiator flushed a few times in the last 5 years trying to clear it up. The last coolant change was last spring. I've had some weird temp issues on and off, but nothing my mechanic is ever worried about.
You said, "I turned on the heater to cold air". Do you mean, you turned the heater control to cold, or you turned on the heat, and cold air come out?

If cold air came out, either no antifreeze in heater core, or control not working, or blockage.

If you have been running for some time, at hot temps this time of year, I would install a new thermostat for sure.

If your hose is soft, time to replace...

Until you can get a repair, you can run with the rad cap in a loose position. Any excess antifreeze should still travel to the overflow container.... I ran a 1500 mile trip like that, putting in water every 100 miles,, small leak.
..
good luck...
Old 02-19-2013, 02:52 PM
  #18  
Newbie
Thread Starter
 
persnickety's Avatar
 
Join Date: Aug 2012
Location: Central Illinois
Posts: 9
Likes: 0
Received 0 Likes on 0 Posts
Year: 1999
Model: Cherokee
Engine: 4.0l
Default

Bob - the heater was set to hot, but only cold air came out.

I stopped at another shop today and he's thinking pretty much that it's either full of sludge or that it might have a cracked cylinder head. He's going to have it next tuesday and he's going to do some compression tests and a radiator flush at least.

What sort of money is this going to cost if it ends up being a cracked head?
Old 02-20-2013, 07:03 AM
  #19  
Member
 
Bob98Classic's Avatar
 
Join Date: Dec 2012
Posts: 200
Likes: 0
Received 2 Likes on 2 Posts
Model: Cherokee
Default

I have not read of any cracked heads on the XJs, but several cracked head gaskets. A cracked head gaskets can make for over heating
problems. Hot gases get into the coolant, causing excess heat which boil away your coolant.
Hopefully the compression test will give you some answers, and a system
flush is always a good thing.
I do not know what a shop charges for anywork, since I do my own
repairs...
good luck..
Old 02-20-2013, 07:35 AM
  #20  
CF Veteran
 
Cherockee's Avatar
 
Join Date: Aug 2010
Location: Williamsport, Pa
Posts: 1,168
Likes: 0
Received 3 Likes on 3 Posts
Year: 1997
Model: Cherokee
Engine: 4.0L
Default

Cracked heads are not common on that particular year model, unless you have a late year model that came with an 0331. I haven't seen and 0331 head on a 99 but I have read that it might be possible.

Aside from that, a bad head gasket could be the problem. There is a "block" test that can easily be done first. The test involves checking for exhaust gases coming out of the radiator, which would tell you a combustion chamder has found a way to get to a coolant passage. The tool I used to do this involved a glass tube with a one way valve on one end. That end is placed on the filler neck of the radiator and the tube is filled with a blue chemical. While the engine is running, and if exhaust gasses are present in the coolant, the blue chemical will turn green. This test will not tell you wether the head is crack or if it's just the head gasket. But once you determined there is definately a problem the head has to be removed. People will tell you this is easy to do, and the process seems simple, but it's time consuming. At repair shop prices it could cost a couple hundred dollars. If it's not the gasket ($50) then the head must be suspect and it will need to be checked for cracks. Replacement heads and related parts could run upward of several hundreds of dollars.

But let's not put the cart before the horse. If your coolant is low the heater inside will not work. If by filling the radiator back up causes you to have heat inside again then it's not clogged- no need to start needless work tearing that apart.

It sound's obvious you're losing coolant somewhere, you just need to find out where.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Aryl
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
12
05-05-2024 10:29 PM
rgr4475
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
9
08-31-2015 01:53 PM
David Chauncey Clothier
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
2
08-29-2015 09:31 PM
bfh_american
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
10
08-22-2015 12:15 PM
Kevin Icenhour
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
2
08-21-2015 08:22 PM

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 


Quick Reply: 99 xj 4.0 radiator issues



All times are GMT -5. The time now is 06:43 PM.