I am still chasing this high heat issue... Not OVER heating but just high heat on normal driving.
I like the ideas coming up, Thanks all!

I'm planning on getting my head examined... engine head... with a device that tests the running coolant with a chemical that will change colors IF there is CO2 in the coolant.. ie. cracked head.

I isolated the heater core or actually took it out of the "loop" BUT really... IF the heater core is blocked wouldn't having the temp/heat slider set to cold keep coolant from flowing through it just the same? AND if you run it to add extra cooling and it works would that tell us it is flowing well?

 

Hood Vent and Scoop!! I run a Chrysler LaBaron louvred vent

 

Yep that was my last attempt at keeping it at 220... I have noticed a little improvement in staying cooler.

 

The Robert Shaw thermostat and GMB High Flow water pump are finally here. I know what I'll be doing tomorrow...

I'll post some temp results after the test drive.


On a side note, I ran into a CF.com member at school (Montana Tech) today. I didn't get his user name, but he was driving a nice blacked out 2dr on 33's. I'm gonna have to figure out who that was...

 

I don't wish to steal this thread either but I have learned a great deal from reading all the posts, I have the same problem with my 03 Grand cherokee(I hope thats not looked down upon as being the leser of the Jeep family)if if I sit in traffic or leave it idle for 5 minutes or so it will creep up to 210-220 and drop down soon as I get moving. It has the I6 in it and has the ovrheating problem when at idle, new failsafe 190 tstat, new fan relay, flushed the system for 20 minutes,water was brown when i started the flush. I have a new water pump i need to install but I am going to check the belt tention suggestion first.

I do intend to make my WJ stand out from the rest, there are way to many stock looking silver lareados out there..

 

If it's heating up when sitting then check your fan clutch. It helps out at slower speeds. 210-220 doesn't sound to far out of line from what I've read here, but FWIW my WJ runs about 190-200.

My problem is the opposite. It can't keep cool at highway speeds or long hills.

BTW: Don't sweat being accepted with the 03 WJ. It's still a Cherokee at heart and it seems that lot's of people have both here (like me - 97 XJ & 02 WJ).

 

Appriciate the kind words of being accepted lol. I didn't think that the electric fan had a clutch. Drove it around today and it never went above 195, I swear by that failsafe tstat, has helped alot. I have heard of several people who installed a constant on switch in the cabin for the fan, so you dont have to worry about it coming on at just a certain temp. Also the additive that is supposed to drop the water temp 20%.

 

I haven't had my WJ long and honestly haven't looked at the fan/s on it. I thought it was set up the same as the XJ with a mechanical clutch fan on one side and an electric fan on the other. I'll have to take a look and see how similar (or different) they are.

 

Just finished up replacing the parts (fan clutch, robertshaw thermostat, GMB high flow WP, 18lb rad cap (for a WJ) without too much trouble and tested it out. I started it up (had the heater on) unti the thermostat opened and the top hose got hot. Then I shut it down and then topped off the fluid. By now it was getting a little dark so I only took it about 6 miles to town to top off the gas tank. With the heater off, it got up to 210, but never above that. Pretty much the same deal on the way back. Tomorrow I'll try taking it on the highway and see how it does on the hills between here and Butte. That'll be the real test, but so far it's looking good.

The only problem I had with the whole project today was a broken hose clamp (had a spare anyway) and the fan shroud split in two pieces. Right now I'm running without a shroud, but I'm looking for a replacement. I've never had any problems with getting hot at slow speeds so I'm not too concerned running without it for a while.

BTW: The WJ fan (1 giant electric) is nothing like whats on the XJ (1 mechanical clutch and 1 small electric). I never knew they were so completely different. Learn something new every day.

 

GoMopar440
You can fix your shroud!

 

I tried epoxying it but all I had was some ancient mystery epoxy in the bottom of my tool box. Now it's all gooped up with that junk that wouldn't stick to itself when I was trying to glue it back together. I had aligned the shroud halves and set it up to dry on the garage window sill so it could cure. When I got back from the test drive, it had finally hardened... after it came apart and fell in the dirt and rocks. Sticky side down of course

 

Of course it would but if things always went perfect we'd never learn other ways of doing something. If you want I’ll tell you how you can repair it AFTER you get the epoxy off, most come off pretty easily. Try to avoid using strong chemicals. Scrape it off with a single edge razor blade or sand it off with 36 or 24 grip sand paper. Don’t worry about the scratches. Roughing it up with 36 or 24 grit paper is the second step of the repair process. The first is wiping it off, one wipe on each surface, with lacquer thinner. Any more than that and it will probably start to soften up the plastic. If you decide that you want to take a stab at repairing it, let me know and I’ll write it all up for you.

 

I know it's still repairable, but the base material is brittle enough that's it's not really worth the effort to me. Unless I can't find a replacement that is.

Today, I took the XJ to out on the highway to Butte (15 miles away)without overheating. There's quite a few hills around here and on the way out there I was hitting a decent headwind most of the way. The temp was holding between 210 and 220 for most of the trip while I was maintaining 70mph. That was with the heater off. Making that trip prior to the parts swap it would keep pushing 220+ with the heater on full blast. So I guess that's about a 5-10 degree improvement overall.

I'd still like to see a lower temp like I'm getting with the 4.0 in my WJ. That one's never reached up to 210 even when going up hills at 75-80mph with the AC on. I guess the next thing I'll be doing to the XJ is swapping out the radiator for a full aluminum 3 core one. I found one (Champion) for $230 shipped on Ebay.

 

FYI: For anyone else planning on running without a fan shroud, watch out for the over flow hose routing. I thought the small plastic clips would be enough to keep the hose off the mechanical fan blades. They weren't. When I popped the hood open today I noticed the overflow hose had been chewed through where it had passed closest to the fan blades. Until I get the shroud replaced I just added some metal insulated P clamps (like these: http://www.alibaba.com/product-gs/27...ose_clamp.html) holding them in place with some self tapping sheet metal screws and washers. I attached the clamps to the upper radiator brace so the hose couldn't come anywhere near the fan blades anymore. Problem solved.

Also, the temp got up to just under 220 going to and coming home from school on the highway today. I put the heat on to keep it from going over that temp and it stayed just below the 220 mark. I'd still rather see the temp stay lower than that so the all aluminum radiator is getting ordered next month for sure.

If that doesn't get the temps where I want it, I've got a few other ideas to try. Next would be a different front bumper that has a lower winch mounting tray. The mounting tray on my TnT bumper sits kind of high. The winch is blocking a good bit of the airflow from the frontal area of the radiator.

The other thing I can try is to swap out the 35's to some narrow 33's. Less wheel and tire weight should put less of a strain on the drivetrain. The shorter tires should work better with the 4.10 geared axles as well.

Any other ideas?

 

So my 2001 xj with 33's was overheating on the trails and also squealing really bad on start up or when my ac was turned on. To fix it I tightened my serpentine belt so tight that I could not move it but only 1/4" and all my problems are fixed