over heating problem

[matt hurtado]

my 92 has been acting weird lately it's been overheating with the a/c on mainly, but still gets pretty close to over heating at a stop light for awhile but once I get going it starts to cool down, I heard the aux fan come on when I pulled in to my driveway. what could be wrong? when I say gets close I mean maybe 130

 

[old88xj]

???? 130 is cool on my 88 210 is normal anything much higher than that i get concerned.....could be a bad thermostat, low coolant several things

 

[AZ Jeff]

Lets' get our measuring scales correct. On a Jeep intended for US markets' we measure in degrees F. In Canada, it's degrees C.

Using degrees F, the NORMAL operating temp for an XJ is about 210, give or take about 5-10 degrees. The electric fan should come on at about 210, if I remember correctly, and thus keep the max temp right at this number, or thereabouts.

If your XJ is seeing idling temps (without the benefit of air being forced through the grille due to road speed) of more than 220, and the electric fan is working, then maybe the viscous clutch on the mechanical fan is crapped out.

If you live in Canada, convert these numbers to degrees Celsius, but the basic specs are the same.

 

[Eagle]

my 92 has been acting weird lately it's been overheating with the a/c on mainly, but still gets pretty close to over heating at a stop light for awhile but once I get going it starts to cool down, I heard the aux fan come on when I pulled in to my driveway. what could be wrong? when I say gets close I mean maybe 130

Forget numbers. Overheating when stopped at a light and cooling down as soon as you start moving is the classic indication that the viscous fan clutch on the mechanical fan has failed. Replace it.

 

[juicexj24]

I agree, but replace the t-stat as well while your at it. Juice

 

[Tony G]

What about when you stop and it starts to boil over .

 

[matt hurtado]

sorry that was 230 not 130 . also tody I t drove normal no overheating at all ran a/c all day in stop and go traffic .
do you still think it the clutch?

 

[Judd W. VA]

My experience so far:

I have been able to fairly accurately diagnose a bad fan clutch on vehicles well in the past. If wobbly, bad. If frozen, bad. Generally otherwise are good. Have yet to find an exception. However, they are really critical on these XJ's so if in doubt, replace it with good quality, like a dealer item. If not dealer, make totally sure you get an equal thermostatically controlled replacement. Don't try to save a few bucks and get one that isn't. Does not lock up enough otherwise when needed. You do NOT want your engine to overheat if at all possible, so spend a few bucks to help to make sure it doesn't.

As another example of how to ck your fan clutch, as when around 100+ here in Utah lately, when taking off from a light i can hear the additional 'whirr' of the fan for a while which tells me the t'stat on that viscous coupling is doing it's thing. Hardly even need the elec fan on my '98 since the replacement of the GDI 3-core with the totally aluminum twin core OEM Up Country radiator that flows better esp at low speeds and sitting. So totally glad i made the switch before driving 2200 miles from home to this sweltering heat. The quality of that rad was amazing and fit so perfectly.

 

[techno1154]

Here in Memphis we are looking at or close to 100 degrees daily. My XJ sitting at idle with the AC on and the AC and fan running constantly, the guage get up to 230+ degrees a few times. When this happens, I quickly turn the AC off or simply drive away then it cools down to 210 +/- . To fix this, I replaced the clutch fan and added the missing mechanical fan shroud $14.95 + tax at the stearlership. Now moving or not, (and today on the overhead console it read 105 degrees) the engine remains a pleasant 210.
For me, I thing the fan shroud made the most difference. It got broken last winter in CT. Did not need it then.

 

[matt hurtado]

thanks you all. I replaced the fan clutch but I broke the fan shrud its still over heating to about 230 in day time heat ,at night it runs 210 while standing still with ac cranking .seems like I need to replace the fan shroud this week