[JasonZ]

First of all, I have searched the previous posts and found similar questions, but nothing that fully answers my question.

I have a 2000 TJ Sahara, 4.0L, stock except for the stereo.

I have had a slow coolant leak for a little while now and haven't been able to find the source. I found some coolant had fallen on the axel and some dripping from between the motor and tranny. The level has never dropped below the "add" line and I have been adding fluid to keep it at or near "full". It also only seems to leak at work...does that mean I can't go to work anymore?

I just went on a trip of a couple hundred miles this weekend and no problems. I was idling in a drive through yesterday at lunch and the "check guages" light came on and beeped. At that point, the temperature was close to redline. I shut it off and checked the coolant. Still above "add" but not very much so I put more in. I think the lid to the reserve tank may have been open.

The temperature then was above the halfway mark (250). The redline is a little above the 3/4 mark. I mad sure to let it get as warm as it would get today on the way to work. It got about halfway between 1/2 (250) and 3/4. When I got into the parking lot I set the parking brake and left the trans in neutral to check the fan, etc. Then the "check guages" light came back on and the temp needle spiked. I turned the engine off. When I turned it back on, temp was just above 1/2 and everything under the hood looked normal. I ran another short arrand and the temp was fine.

Questions:
What is the normal temp that your TJ runs at?
Any ideas on what the problem is?

Thanks

[Jerky bump]

I've read people usually speculating -water pump-clogged rad-fan clutch. -I mean roughly for those conditions.

[jeepramnauth]

buy and run some coolant sealant fluid

[RLD831]

Adding coolant to the bottle won't help if it is already hot. You need to put more coolant into your radiator. Just don't take the cap off when it is hot either. The normal temperature is 210 degrees. You should hose the engine bay down and dry as much off as you can then park it on level ground and fill up the radiator. Maybe even throw some cardboard underneath it so you can see the drops and look for when it gets wet with coolant.

[Rollin]

Might be mud in the radiator, bad water pump, or a thermostat.

[JasonJW]

How many miles? Is your drive to work your shortest drive, typically? Ever replaced your thermostat? Water pump? Radiator clear? Any coolant in your oil?

[DakarTJ]

Mine did just what you are describing. I let it go for a couple of months. It finely blew out the weep hole.

[glp06unl]

Originally Posted by Rollin

Might be mud in the radiator, bad water pump, or a thermostat.

I had that happen to me before. Mud between the AC ans radiator. Ran water between the two and flushed the mud away.

[JasonZ]

Thanks for all your suggestions. The more I looked at it, it looked like the water pump was the source of the leak, so I replaced it. I also put in a new thermostat and serpentine belt while I had it all apart. It hasn't leaked in the last two days. I think I'll still go ahead and make sure everything is cleaned out like some of you said.