2000 tj overheating

jscusmcvet

Explorer
My son's 2000 TJ is overheating. It has 140k miles and other than this, runs like a top. Overheating happens when sitting still. You can hear the coolant boiling when engine is turned off. It seems as though the fan is operating correctly. Coolant is correct color/consistency. I have replaced thermostat. I have "burped" the air from the system. I plan on replacing the radiator cap tomorrow. The other things I can think of are paying a shop to do a full flush and if that does not work replace the water pump and then the radiator.

Are these the correct next steps? Any other suggestions? Trying to finish before Sunday when he wants to take it back to college. Any help would be appreciated.

John
 

jscusmcvet

Explorer
Upon further review, I wonder about the fan clutch. Should the fan always spin with force? If I can stop it by hand when the engine is on, does that mean it is bad?
 

s5m

New member
Upon further review, I wonder about the fan clutch. Should the fan always spin with force? If I can stop it by hand when the engine is on, does that mean it is bad?
Yes when the engine is at operating temperature the fan clutch should be locked. I would replace the radiator cap, fan clutch, thermostat and coolant. and see if that fixes the overheating issue.
Sam..
 

evilfij

Explorer
If the fan clutch is weak that will do it, but for the cost of a new rad ($150) I would change that too. That fixed my TJ's overheating issue.
 

Judoka

Learning To Live
Biggest concern is fan clutch. Easy to fix on a TJ. If that does not fix it, replace radiator and cap. Now... If it still overheats then check for blow-by which is somewhat common on the 4 liter, which is often caused by a weak head gasket. Owning two TJs will teach you about that!
 

jscusmcvet

Explorer
Little update. I appreciate the suggestions and am working my way through, as work/family/etc... allow

I replaced the radiator cap, still ran hot. Cleaned radiator/ac condenser and between them as best I could, used simple green and water pressure... definitely needed it but still ran hot. Stopped to get the system flushed at a service station, and mechanic looked at it, he said a fan clutch is next step because:
1) with the jeep at operating temperature when the jeep is restarted the fan does not lock up upon starting
2) overheating only occurs when engine is relying on the fan to do the cooling.

Made sense to me, and was next in line as far as inexpensiveness goes, so picked up a fan clutch on the way home from work. Will try to get it put on tonite when I get home from work. Mechanic suggested doing this first, then do the flush... because he is certain it is the fan clutch... I will do the flush anyway, was just trying to save time by having them do it over my lunch break.

Also definitely have some death wobble going on and isolated that issue to the axle side track bar. It is apparent that the previous owner did some customization, nice work actually, by welding some 3/16 steel onto the mount and remounting stock TB in stock location. I am going to try and pick up an adjustable TB today and redrill a new hole. I cannot tell if the play is coming from a worn TB or a wallowed hole in the mount, so this plan should address both issues.

Thanks again for the help. After I do the fan clutch I will post back up.

John
 

jscusmcvet

Explorer
Success! Changed out the fan clutch today and that seemingly did the trick on the overheating issue. I am headed to the coast tomorrow to pick up Jonah and we'll finish up on Saturday with the track bar. I have the track bar off, and clearly I am going to have to drill a new hole. The bolt is wrecked and the holes are wallowed out. I bought a new track bar and need to pick up a bolt tomorrow... In theory, it will just be bang out a new hole and bolt it all up... let's hope so :)

Really want to say thanks for the advice and suggestions.
 
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Judoka

Learning To Live
Hey. while you are in there fixing the track bar maybe you should put in a Rubicon Express Adjustable Track Bar. They require reaming the track bar bracket on the frame anyway. That way you will not need to weaken the existing track bar by reaming it to fit the bigger bold for the new hole.
 

jscusmcvet

Explorer
Hey. while you are in there fixing the track bar maybe you should put in a Rubicon Express Adjustable Track Bar. They require reaming the track bar bracket on the frame anyway. That way you will not need to weaken the existing track bar by reaming it to fit the bigger bold for the new hole.

The frame side is doing great. The axle side bracket has been modified and needs a new hole drilled... even if I go with an aftermarket tack bar with a bigger bolt. The mod done to the axle side bracket is 3/16" plate welded over the stock mount. It was well done, but the bolt used was too soft, got deformed and in it's wiggling deformed the holes. No choice but to drill a new hole, weld a new bracket on or find another way to mount the track bar. Drilling a hole costs me nothing and might just solve the issue so that is the way I am headed. If I drill the hole and then have to back up and need to go adjustable... at the most I will need to redrill that same hole to fit a bigger bolt.

Won't get to it til Saturday it looks like.
 

s5m

New member
If you have a death wobble also check the front lower and upper control arms if it has an aftermarket control arms check the bushing. Sometimes you have to remove the arm to inspect the bushing. And if they are urethane bushing, there is a good chance they are worn out. I had death wobble on two jeeps I have own and after changing out he urethane bushing the wobble went away. Also run a heavy-duty steering damper Hope this helps.
PS Check the rear track bar bolts sometime they come loose.
 

jscusmcvet

Explorer
Final update.. I hope:smiley_drive:

Overheating issue taken care of, at least for the time being. I think we'll do the water pump, hoses and radiator at some point down the road, just because, then it will be a new cooling system.

Drilled new holes and installed new track bar. At some point we are going to get the boy an adjustable to make everything perfect. I drove to my favorite death wobble inducing spots and everything feels tight... no DW.

I appreciate everyone who responded and helped me chase this stuff down. With Jonah at college I had just a limited time, which precluded mail ordering anything. With your help I was able to knock out one thing after another and get this solved. Jonah is home and will be leaving back for college tomorrow, so I am happy to know that with a 2.5 hour drive, the jeep is in better shape than when he came home with it.

Thanks again.

John
 

jscusmcvet

Explorer
Confirmation...

Jonah called and said no DW and no overheating on his way back to college... 2.5 hours and some road construction areas that are DW prone, so I have some confidence in my fix now.

John
 

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