PDA

View Full Version : 98 Jeep Cherokee running a little toasty.


dellstopjeep
July 25th, 2017, 20:40
Well sometimes you just need to ask someone when you can't figure it out...
1998 Jeep Cherokee noticed its was running around 215 around town and climbing to 225 on highway. For some reason once gauge has reached 225 it jumps right up to red and throws a check gauge light and high idle but then comes down when I slow the rig down or turn off ac for a bit.... with that being said it boiled over in me once so i know it gets toasty verified with thermometer.

Then I replaced thermostat, fan clutch, csf 3 row radiator, water pump... deleted a inline hot water exchanger on heater hose for hot water to eliminate a clog issue... burped system gave it a new stant radiator cap and results have not changed. Radiator hoses checked and not collapsing under pressure.

Still running about 215 around town and climbing to 220-225 on freeway.. on a steep grade it will climb a little more. No winch blocking radiator, spaced hood for airflow.

The rig has a newer coolant temp sensor... could this possibly be the issue? Thoughts on what else it could be?

dellstopjeep
July 25th, 2017, 20:41
Oops... this should be moved to oem tech my bad.

Green XJ Jeep
July 25th, 2017, 21:04
Ambient air temp and road temp is going to have an impact also. When I am on the east side and temps are 100+, 240 is about average with the ac on high.

blakews2217
July 25th, 2017, 21:16
Ambient air temp and road temp is going to have an impact also. When I am on the east side and temps are 100+, 240 is about average with the ac on high.



Same. I pulled my boat( about 5000#) up a steep grade with the air on. She went to 245 and stayed there till the top and went to 250. By then I could let out and cool her down.


Sent from my iPhone using Tapatalk

dellstopjeep
July 25th, 2017, 21:32
I'd love to think this is my problem.... but it's been hot here since early June and the problem is consistent. Of course not as bad in the morning or up in cooler mtn temps... I think something is going on

blakews2217
July 25th, 2017, 21:39
Possably a fan clutch biting the dust? Also. How recent was a coolant flush?


Sent from my iPhone using Tapatalk

dellstopjeep
July 25th, 2017, 21:41
Brand new fan clutch. When replacing water pump and radiator last week it got new coolant. Old coolant was still green and clean

techno1154
July 26th, 2017, 15:32
Brand new fan clutch. When replacing water pump and radiator last week it got new coolant. Old coolant was still green and clean

Does the electrical fan run when the AC is on?

dellstopjeep
July 26th, 2017, 17:19
Yes. Runs like it should with ac on and when temp creeps up. Ac on or off only slightly enhances the problem a little more.

Hopkins
July 27th, 2017, 04:53
I've been through all this on my 98. Replaced everything in the coolant system - water pump, radiator, fan clutch, etc... Still liked to get too hot. Finally installed hood vents and problem solved. Our engine compartment holds heat like an oven and needs a significant improvement in ventilation for effective cooling. I went with the Daystar hood vents for the XJ and couldn't be happier.

Yzzerdd
July 28th, 2017, 07:45
Yes. Runs like it should with ac on and when temp creeps up. Ac on or off only slightly enhances the problem a little more.

What did the coolant look like when you flushed it? If it was rust-brown, it may take several fluhes to clear the system of rust, etc, which is holding heat.

In my experience, 4 flushes cleared out the rust, and my coolant has remained green. After the first flush, it was back to brown after 200 miles or so.

J

dellstopjeep
July 28th, 2017, 09:44
Fluid was green and good looking.

Yzzerdd
July 28th, 2017, 22:14
Fluid was green and good looking.



Good. I've only had 2 4.0's, both with AC-Delco pumps, fresh flushes, new hoses, and dual-core radiators. In the same conditions, and with 100K miles of difference between the two motors, they both run dead-center on the temp gauge constantly once warmed up. A long run on a steep grade will push mine to 215, but cools quickly.

At op temp, no bubbles in the overflow tank while running? Fan shroud(s) in place? If you don't have a trans cooler, consider adding one. Otherwise, you could check your trans temps to see if the heat is happening there.

Finally, check your radiator for even temp distribution. Material may have dislodged and relodged in the rad.

J

dellstopjeep
July 29th, 2017, 07:10
No bubbles. Fan shroud in place. I have an aftermarket Trans cooler and bypassed heat exchanger in radiator to see if it would help. It is a brand new 3 row radiator.... the previous one was a single row and problem hasn't changed at all. So I am guessing problem isn't in the radiator.

comanche91
July 29th, 2017, 09:14
I've been through all this on my 98. Replaced everything in the coolant system - water pump, radiator, fan clutch, etc... Still liked to get too hot. Finally installed hood vents and problem solved. Our engine compartment holds heat like an oven and needs a significant improvement in ventilation for effective cooling. I went with the Daystar hood vents for the XJ and couldn't be happier.

Went through all that too. You're right, there's just not enough real estate under the XJ/MJ hood for decent air movement. I was lucky enough to find a used cowl hood. Temps are always stable now.

http://i.imgur.com/zOfZhnx.jpg

Rod Knee
July 29th, 2017, 10:53
I went for several years with the same problem which was rising temps at highway speeds which was alleviated by slowing down. I knew it couldn't be my cfs 3 row radiator because, as I had been told, this was the best radiator that you could put in an XJ. Changed everything else in the cooling system multiple times with no improvement ever. Finally my big and bad-@$$ cfs 3 row started to leak so I replaced it with a stock radiator. Guess what..no more overheating problem.

At least one other person on this forum has posted this same experience that know of.