sportrider

what is the average coolant temp your gauge shows. on my old ZJ it stayed at 207(aprox), my XJ seems to stay at 212(aprox) when I hook up a scan tool it will climb to 215 then drop to around 210 and repeat. just curious what everyone else is reading. summers coming, I was thinking about replacing the T-stat and radiator just for prevenative maintance.

weebur

You may be running a few degrees on the warm side, but replacing a radiator for PM? If I had your money I'd burn Mine!

Here's what a well respected guy (from "down under") has to say about running temps:

Please use a stock 195*F temperature one so as your computer wont think it is still in the warm up cycle and stay in open loop, meaning the O2 sensor is not read and you run rich. Also, the higher the temp you can get the more efficient your engine is. Engineers are running the temperatures higher as materials and designs improve. For every 10F under 180F your engine wear rate doubles due to chemical reactions on the surface of the cylinder walls. Running a 160F thermostat QUADRUPLES your engine wear rate. For every mile you drive your engine wears like it has been driven four miles. The chemical reactions drop little abrasive oxide particles in the oil that eats up the bearings and everything else as well.

A very good site to check out anyway: http://www.go.jeep-xj.info/HowtoWaterpump.htm

nickxj94

My 94 runs @ 210 in town,and 195 on the highway if that helps I have a 195 t stat in also,and Hood vents and rasied the rear of the Hood up a inch it helped a bunch,use to run hotter than that before I did the mods

sportrider

it's probably fine, I just like to see the gauge under 210. the main reason I'm considering replacing the radiator is because it's OEM. I changed out the OE radiator on my wifes 95 XJ a few years back due to a cooling issue, I had replaced a leaking water pump & T-stat and flushed the system and it would still overheat. when I replaced the radiator I broke open the tanks on the old one and they were full of sediment that was restricting flow. I've owned my 99 for a few months now and have had to fix a few PO neglections. I see spending the $130 on a radiator as cheap insurance.

jakbob

i dont know why anyone else never mentions the mechanical fan clutch...

sportrider

my fan clutch looks good, its not that it runs hot around town it's consistant freeway,town, out wheeling. doesn't get much hotter.

djb383

.....me neither. LOL

https://www.cherokeeforum.com/search...archid=3157459

djb383

How do the scan tool numbers (the range) compare in winter below freezing ambient temps (running the heater) to summer high ambient temps (running a/c)?

jakbob

it can "look" good but be bad actually. like a coil pack can "look" good but really isnt. take a rolled up newspaper, and with the motor running, take said newspaper and try to slow the fan down.

the way the fan clutch works is that the hotter it gets, the faster it spins. a viscous clutch can go bad and you wont know it.

sportrider

I've only owned this XJ a few months so I'm not sure about summer temp yet

djb383

......might be surprised.

djb383

Sticking anything in a spinning/rotating fan is not advisable and is not how to test a fan clutch.