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Topic Review (Newest First)
05-23-2013 01:51 PM
Neil F. If you only bought it a week ago, did you start with the place you bought it from?
05-23-2013 01:32 PM
Originally Posted by stephandjay View Post
Thanks everyone. We drove it to Jeep dealership (this is not where we bought it) this morning. We don't know someone who works on jeeps. They just called my husband and said its going to be $1500 and told us pretty much everything has to be replaced. I definitely want a second opinion.

WTH is "pretty much everything"?? WOW!

Jeeps aren't like a Mercedes or some exotic European car. Any decent mechanic can work on a Jeep. You don't need a Jeep specialist. Ask some friends for a mechanic reference or two & take it in for a 2nd & 3rd opinion.
05-23-2013 11:46 AM
DaveCR $1500 sounds too high.. unless something else happened like a crack head or something like that...
05-23-2013 11:42 AM
stephandjay Thanks everyone. We drove it to Jeep dealership (this is not where we bought it) this morning. We don't know someone who works on jeeps. They just called my husband and said its going to be $1500 and told us pretty much everything has to be replaced. I definitely want a second opinion.
05-23-2013 10:57 AM
OrdieCPO I had the exact same problem on my 1999 TJ. When I purchased it after a couple days of normal driving same thing happened as you described. Come to find out the previous owner replaced the radiator and water pump prior to me buying it. The wrong PSI radiator cap was used, I replaced it with a 18 PSI cap and no more issues.
05-23-2013 09:45 AM
Neil F. First, make sure the system is full. When cool, remove the radiator cap and ensure the radiator cap and fill as required, then add to the reservoir/overflow. The level in the reservoir is only going to go down as the system cools. When the coolant heats up, it expands, pushes up on the cap spring and flows into the reservoir. When the system cools, the coolant contracts and fluid is pulled back from the reservoir. (not having the cap on the reservoir really is not an issue)

Do not get a fail safe thermostat. Those are more problematic than they are worth.

Get more information on when it is over heating:

- Is the temperature continously rising or does it just spiking up?

- Spiking can be caused by low coolant to begin with or the cap is not maintaing pressure and allowing the coolant to boil. Note, weak coolant will boil at a lower temperature.

- When driving on the highway or at speed, the normal air flow provides much of the cooling and the fan is not necessary. Overheating here points to poor airflow through the radiator or poor coolant flow.

- In stop/go driving, the fan must provide cooling. Overheating here can be the fan clutch.
05-23-2013 09:18 AM
DaveCR What I did was to replace the thermostat, upper hose that was old anyways, radiator cap and water pump cause it was leaking...

I think this is very common on Jeeps our age hehhe. Mine is a 98..

Not a difficult problem to fix but it takes time to troubleshoot ... or u can just replace the whole thing if you want to be pro active
05-23-2013 07:06 AM
Mwagner My 98 keep overheating but I put a new radiator cap on and it solved that problem
05-23-2013 05:44 AM
MosesTJ Just went thought this last week. Check to see if both radiator hoses top and bottom are hot. If the bottom is not hot then the water pump might be your problem. Also check to see how fast your fan is spinning, if you can see the blades then you need a fan clutch. This is not uncommon if the truck has been in deep mud/water.
At the age of the truck I would check the fan first but it's probably the radiator cap or tstat. Start with the easy stuff first. You can pm if you need anything else.
05-23-2013 02:44 AM
Maroon Turtle My 99 jeep also had this problem when I bought it. You might want to change the thermostat. The factory thermostat stays closed or at least may stay closed when it fails. If this happens then your thermostat goes from regulating heat to turning into a plug.

By the way if you are going to check it you might as well just buy a new one and replace it because you'll need a new seal for it to put it back on. If I'm wrong worst case your out a few bucks. Also, I'd upgrade the thermostat to the one that just stays open if it fails.
05-23-2013 12:07 AM
Originally Posted by DaveCR View Post
Well I think that if the radiator cap was leaking you have a problem right there..

This was definitely where the steam was coming from when we lifted hood. I've always owned volkswagens and not used to being able to even see any of the parts under the hood. A vw slightly messes up and you send it off to the shop. No need to even lift the hood on those! Any clue what we may be looking at replacing?
05-23-2013 12:01 AM
DaveCR Well I think that if the radiator cap was leaking you have a problem right there..
05-22-2013 11:52 PM
1999 Radiator Issues?!- Coolant??

We are first time jeep owners of a 99 sahara as of a week ago. So excited BUT today suddenly the car overheated/ the "check gauges" light came on and at the same instant the temp gauge was in red. Before I could even pull over the gauge had gone back down so I went to store and all was fine. Totally fine yet again on way back home, then right when I was pulling into driveway at home, temp gauge spiked back up and check gauges light flashed on again. As I pulled in steam? began coming from under hood. We opened hood and it's clearly coming from around radiator cap. The level looked low on coolant and also noticed the cap was missing from the reservoir bottle that holds the radiator fluid. The previous owner had plastic wrap like cover on it. We went to auto parts store to get more fluid and they said it appeared to have jeep stock antifreeze and jeep dealer is closed for day so they recommended to just add water to see if a leak.

We added some water and drove jeep back around block and it heated quickly again! The water/coolant in bottle didn't appear to be lower. The person at auto parts store said when jeep is on if we are able to "pinch" the hose from botle to radiator there is a problem. The hose was "pinchable." Any advice?? We are new jeep owners and frustraed since just bought last week. this is a 99 with 105,000 miles on it! We have a jeep dealership near our house. We don't know our own jeep mechanic so i guess this is where we will take it??

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