XJ: over heating help please

[bails85]

i got an 89 xj but i cant keep it cool. i just had the motor rebuilt, brand new radiator, upper and lower hoses, thermostat, fan clutch, pressure cap, i just put 3000 into this thing and still cant get it to run cool. any help is appreciated

[xjkevin]

did you burp the air bubbles out from the system, that did it for me.....

[inVERt'D]

I'm sure the timing is computer controlled on that vehicle year; retarded timing can make an engine run hot. Did you remember to put oil in it?

I'm betting xjkevin is on the right track...

[xjkevin]

raise the rear of the jeep till the rear of the head is higher than the front, you want the temp sending unit to be the high point after you jack it, remove the sending unit and add water into the res until the bubbles quit comin out and its burped,,,i would try this first then get a new thermostat as ive had 2 new ones not work for me....good luck

[New2image]

all good points and to ad to it

1.Redline water wetter

2.Gen-Right Hood louvers

Got a friends XJ to run really cool if you want to go the extra mile

Ford Taurus electric fan pusher type.
Nice trick we learned

[Guest]

Taurus fan goes on the front side of the radiator? I was told it doesnt cool that good. Do you disagree?

[tgregg]

I put on a brand new fan clutch that was bad. Replacing it with a better one solved my problem. XJ's run hot but I got mine to run at 210 to 220 with air running. I was told that a 180 thermostat also makes them run hotter, I have a 210 in mine now. I have a pressure tester to test radiator and cap if you want to come by the house we can test.

[Guest]

I put on a brand new fan clutch that was bad. Replacing it with a better one solved my problem. XJ's run hot but I got mine to run at 210 to 220 with air running. I was told that a 180 thermostat also makes them run hotter, I have a 210 in mine now. I have a pressure tester to test radiator and cap if you want to come by the house we can test.

I personally disagree. I have a 180* stat in my Avalanche, Dodge, and Jeep. It just opens sooner is all. Does this alone keep it cooler? Sometimes, yes, sometimes, no. Again, it just opens sooner to start cooling it down sooner than a 195*.

[tgregg]

I personally disagree. I have a 180* stat in my Avalanche, Dodge, and Jeep. It just opens sooner is all. Does this alone keep it cooler? Sometimes, yes, sometimes, no. Again, it just opens sooner to start cooling it down sooner than a 195*.

I disagreed also so I tried both and on my 95 4.0 motor it seems to be true. To pass smog my Jeep also needs the higher temp but if it had run cooler with the 180 I would have changed it to smog. Redline Water Wetter does help also but needs to be replaced for winter by antifreeze. I used to sell Redline products and it was really made for track racing where antifreeze was against the rules. I also have my fan on a switch and I just leave it on most of the time in warm weather When I got the XJ some one had reverse wired it so it was blowing the wrong way, that didn't cool it off very well LOL
I have a two core and I've been told the three would work better but there is lots of discussion on the XJ forum about aluminum vs copper vs plastic. When mine goes bad I'll put in a three core and think I'll look for aluminum. The one thing that made all the difference on mine was the new fan clutch.

[2blk2drs]

Taurus fan goes on the front side of the radiator? I was told it doesnt cool that good. Do you disagree?

As i understand it putting a fan in a pusher position is less efficient than as a puller,

However my xj runs too hot for my tastes as well, and i have considered the taurus fan as a replacement for the factory electric fan as a puller. Most people tend to replace the mechanical fan and have two electrics.

heres a page on how go-jeep did it

http://www.go.jeep-xj.info/HowtoTaurusFanInstall1.htm

[Drewminator]

Well at least you both agree to disagree...:gun:

[kirkandsylvia]

I had the same problem with my 96 XJ until I put the Heat Buster radiator in. The three core vs. the stock two core made a ton of difference. I personally couldn't see my motor running up to 220 + before the fan kicked in, so I too put a bypass switch in to control the fan manually. On a day with temps busting the triple digits, my engine will run right at 200 ( nice safe temp )

[tgregg]

You can find more info than you'll ever want to read about over heating at www.naxja.org/forum/
In the interest of full disclosure I've been a long time member there. But when it comes to XJ's they have been very helpful.

[Mitch]

Interesting stuff.

My 4.2 YJ runs 210'. No matter what I do it runs 210'. I've learned that most Jeeps run there and it is fine. As far as the things I did and thought would help are:

Installed high flow water pump (no change)

Installed an "Custom Aluminum Radiator" (no change)

Installed four Genrite Hood Vents (no change)

Replaced the fan clutch (no change)

40% Prestone Anti-freeze

1 bottle of Purple Ice (no change)

So good luck to you.

Mitch

[Guest]

I disagreed also so I tried both and on my 95 4.0 motor it seems to be true. To pass smog my Jeep also needs the higher temp but if it had run cooler with the 180 I would have changed it to smog. Redline Water Wetter does help also but needs to be replaced for winter by antifreeze. I used to sell Redline products and it was really made for track racing where antifreeze was against the rules. I also have my fan on a switch and I just leave it on most of the time in warm weather When I got the XJ some one had reverse wired it so it was blowing the wrong way, that didn't cool it off very well LOL
I have a two core and I've been told the three would work better but there is lots of discussion on the XJ forum about aluminum vs copper vs plastic. When mine goes bad I'll put in a three core and think I'll look for aluminum. The one thing that made all the difference on mine was the new fan clutch.

So, it didn't pass smog with the 180*? I didn't know that. I have ran them before without issue. Maybe on those vehicles I had new cats which made a difference?

The taurus fan mounts on the front side of the radiator? I thought there was three wires? Hi, low and ground? How did they reverse wire it? Unless I am wrong?

Also, how to you tell how many rows you have on your radiator? I was told I have a bigger radiator. I wanted to count it.

Thanks