Modified XJ Cherokee Tech XJ (84-01)
All modified tech questions. If it modifies your XJ beyond stock parts ask it here.

Overheating issues

Old 01-25-2019, 07:54 PM
  #1  
Member
Thread Starter
 
Join Date: Sep 2018
Posts: 136
Likes: 0
Received 0 Likes on 0 Posts
Year: 95
Model: Cherokee (XJ)
Engine: 4.0L
Default Overheating issues

So, I live in a place where outside temp goes as high as 108F during the day and average temperature is 98F.

I have installed a 3 row radiator, changed the water pump and removed the thermostat, as well as replaced the fan clutch and main fan, however my XJ still goes higher than 210 and eventually shuts off by itself and wont let me start until it cools down.

I'm going to regear from stock to 4.56 and don't know if that would change anything

Does anyone have any suggestions?

Ps. It rains really really heavy during rainy season and hood vents would mean a lot of water going in the engine compartment.
Rikrdolevy is offline  
Old 01-25-2019, 10:48 PM
  #2  
Junior Member
 
Join Date: May 2018
Location: SoCal
Posts: 35
Likes: 0
Received 0 Likes on 0 Posts
Year: '96
Model: Cherokee (XJ)
Engine: 4.0L
Default

check for head gasket leak. not common in '95s though. use a thermostat from mopar dealer. 180 or 195. engines overheat without a thermostat; someone smarter than me will tell you why. flush the coolant really well. and the heater core. bypass the heater core if it's trashed. bypass the radiator for your trans cooling. replace the temp sensor, mopar. install an aux fan override and have it going all day every day. 100F is really hot. it's going to be hard on that engine, which already runs hot from the factory. i went to a greater capacity radiator and it solved all problems (mishimoto). none of this is guaranteed. you throw money at it until it's fixed. i started small and finished big with the $400 mishimoto rad.

Last edited by msumms; 01-26-2019 at 09:36 AM.
msumms is offline  
Old 01-26-2019, 01:52 PM
  #3  
Member
Thread Starter
 
Join Date: Sep 2018
Posts: 136
Likes: 0
Received 0 Likes on 0 Posts
Year: 95
Model: Cherokee (XJ)
Engine: 4.0L
Default

Originally Posted by msumms View Post
check for head gasket leak. not common in '95s though. use a thermostat from mopar dealer. 180 or 195. engines overheat without a thermostat; someone smarter than me will tell you why. flush the coolant really well. and the heater core. bypass the heater core if it's trashed. bypass the radiator for your trans cooling. replace the temp sensor, mopar. install an aux fan override and have it going all day every day. 100F is really hot. it's going to be hard on that engine, which already runs hot from the factory. i went to a greater capacity radiator and it solved all problems (mishimoto). none of this is guaranteed. you throw money at it until it's fixed. i started small and finished big with the $400 mishimoto rad.
Well i dont understan why should i put a thermostat if its always hot out there and the engine is always running hot, I had a MotoRad thermostat installed but decided to remoe it as it did not make much sense to have one in the firts place.

Did you try any other type of aluminum radiator before the mishimoto?
Rikrdolevy is offline  
Old 01-26-2019, 08:26 PM
  #4  
Senior Member
 
mikesignal's Avatar
 
Join Date: Aug 2009
Location: north carolina
Posts: 844
Likes: 0
Received 0 Likes on 0 Posts
Year: 2000
Model: Cherokee
Engine: 4.0
Default

Maybe you've got a blockage somewhere, and coolant flow is restricted. I would make sure to flush the entire system out. Also don't forget the transmission is cooled by the same system, so that could cause temps to rise too.
mikesignal is offline  
Old 01-26-2019, 08:41 PM
  #5  
Senior Member
 
downs's Avatar
 
Join Date: Oct 2018
Location: Hunt County Texas
Posts: 601
Received 4 Likes on 4 Posts
Year: 1995
Model: Cherokee (XJ)
Engine: 4.0L
Default

Originally Posted by Rikrdolevy View Post
Well i dont understan why should i put a thermostat if its always hot out there and the engine is always running hot, I had a MotoRad thermostat installed but decided to remoe it as it did not make much sense to have one in the firts place.

Did you try any other type of aluminum radiator before the mishimoto?
One of the things the thermostat allows the coolant to do is "sit" in the radiator bleeding off extra heat until it's needed in the engine block. By removing it, coolant is cycling as fast as the pump can pump it and you're loosing some cooling capacity.
downs is offline  
Old 01-26-2019, 08:58 PM
  #6  
Member
Thread Starter
 
Join Date: Sep 2018
Posts: 136
Likes: 0
Received 0 Likes on 0 Posts
Year: 95
Model: Cherokee (XJ)
Engine: 4.0L
Default

Originally Posted by downs View Post
One of the things the thermostat allows the coolant to do is "sit" in the radiator bleeding off extra heat until it's needed in the engine block. By removing it, coolant is cycling as fast as the pump can pump it and you're loosing some cooling capacity.
Temp raises to 108 outside, coolant would never "sit"
Rikrdolevy is offline  
Old 01-27-2019, 12:26 AM
  #7  
Junior Member
 
Join Date: May 2018
Location: SoCal
Posts: 35
Likes: 0
Received 0 Likes on 0 Posts
Year: '96
Model: Cherokee (XJ)
Engine: 4.0L
Default

I did not replace the radiator until I went to the mishimoto. So the radiator probably isn’t your issue.

of course the coolant would sit with a t stat. As it should. If it’s 108 outside your car will start at 108. And then it will hit 195 and the therm will open. It opens gradually allowing coolant to sit for longer at the radiator before fully open. If the coolant is being partially restricted at operating temp as it should be, it will be getting exposed for a longer period of time to air moving in front of it at the radiator; and therefore cooler by the time it reaches your engine. You should always run a t stat. But that may not be your issue if you were already overheating. However you won’t know if you’ve fixed the problem if you’re still overheating due to no tstat.

I think you have a blockage somewhere. Sometimes you have to flush these things 10 times. It can be at the heater. It should burp on its own for the most part. On older systems you need to let it run with the cap off and the heater blowing. Speaking of which, are you getting choking hot heat? Check at night when it’s cooler. It should be blazing hot at full blast when your engine is up to temp. In your climate you need an aux trans cooler. The hot trans fluid in the radiator transfers heat to the coolant nearby.

Good luck. This drove me crazy. I never overheated while driving, but at idle and low rpm it would
kick up to 225 before the aux fan could control it. My process was:
reverse flush coolant many times. This helped slightly.
replace fan clutch. No help.
replace aux fan. No help.
replace both temp sensors with dealer parts. No help.
replace old crusty ccv valves. No help.
replace many rad caps.
flush and burp the **** out of the coolant again. No help.

replaced t stat w dealer 195, dealer water pump, and replaced the mopar hd cooling radiator in there from PO with mishimoto aluminum. Now sits at 210 like a rock in SoCal summer. On desert climbs in 4x4 it will rise a bit. 220 is ok. On obdii it’s even cooler since the temp sensor for the computer is at the front of the engine. In fact, once it hits around 210-12 at the gauge, the temp will actually fall slightly back down, even at idle. That’s the t stat opening up more, and the cooler water rushing in.

I have a stock mopar trans cooler that was part of the towing package.

Before this odyssey I would regularly hit 223 at idle or higher. Once I hit 235 on a climb and decided that was it time to pull the rad, pump and tstat. Never had an issue since and I’m running the xj clutch. Now on long climbs I can hit 220 or so but I’m talking 7k feet of climbing nonstop at low rpms, on unpaved hardpack and washboard with my tires at 12-15psi

Last edited by msumms; 01-27-2019 at 10:35 PM.
msumms is offline  
Old 01-27-2019, 01:13 AM
  #8  
CF Veteran
 
Turbo X_J's Avatar
 
Join Date: Sep 2009
Location: ☼ Blackhole Sun
Posts: 8,567
Likes: 0
Received 1 Like on 1 Post
Year: My Jeep is a GMC
Default

Originally Posted by Rikrdolevy View Post
Does anyone have any suggestions?
Temperatures verified with an IR heat gun?
Is the cooling system contaminated with any type of "stop leak" substance?
Perform a compression and/or leak down test.
Anything thing other than OEM style cheapie radiator is not necessary. A thermostat is necessary to restrict flow through the cooling system for maximum heat dissipation.
Turbo X_J is offline  
Old 01-27-2019, 03:58 PM
  #9  
Senior Member
 
downs's Avatar
 
Join Date: Oct 2018
Location: Hunt County Texas
Posts: 601
Received 4 Likes on 4 Posts
Year: 1995
Model: Cherokee (XJ)
Engine: 4.0L
Default

Originally Posted by Rikrdolevy View Post
Temp raises to 108 outside, coolant would never "sit"
Yes it does, well maybe sit is the wrong word. But, As stated above the thermostat gives the system a restriction that slows coolant flow down and allows the coolant to bleed off more heat though the radiator before cycling back to the block/head.

I've wheeled in the socal desert during the summer time and in Texas when temps were over 110 with a fully stock cooling system. If the system is working properly and you don't have a headgasket leak or a badly worn timing chain the stock system works just fine.
downs is offline  
Old 01-28-2019, 03:36 AM
  #10  
Member
 
Join Date: Oct 2017
Location: Indy
Posts: 212
Likes: 0
Received 0 Likes on 0 Posts
Year: 1991
Model: Cherokee(XJ)
Engine: 4.0L L6 OHV 12V
Default

Originally Posted by mikesignal View Post
Maybe you've got a blockage somewhere, and coolant flow is restricted. I would make sure to flush the entire system out. Also don't forget the transmission is cooled by the same system, so that could cause temps to rise too.
I wonder how much difference a transmission cooler makes? Msumms mentioned earlier in this thread that he has the Mopar tow package factory cooler installed.

Last edited by Rlmx; 01-28-2019 at 04:05 AM.
Rlmx is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Cyriac
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
17
07-06-2012 06:03 PM
awfulmel
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
6
05-14-2010 11:55 AM
awfulmel
Cherokee Chat
2
05-13-2010 08:07 PM
89Cherokee
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
6
03-17-2009 10:46 PM
nodgesh
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
2
09-29-2008 11:54 AM

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 

Thread Tools
Search this Thread
Quick Reply: Overheating issues


Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
 
  • Ask a Question
    Get answers from community experts
Question Title:
Description:
Your question will be posted in: