Getting hot offroad

[chrisvv]

UPDATED: I recently went out on the local trails up and down pretty good sized sand pits and put her through a mild workout.

NO HEAT LIGHT CAME ON! But, as an experiment I ran the heater full blast the whole time. So maybe this will help me get some ideas...

-----So here is what is happening.--------------------------

I just picked up my first jeep, it is a 95 Cherokee SE No tranny cooler.

I have read all the overheating threads on here and have run through all the common fixes, checked all the hoses, coolant, flushed and re-flushed and flushed some more.

I have flushed with the small hose on the thermostat disconnected.

I cant figure this out.

Driving around on the street in 2h is fine. No light comes on. (All I have is the idiot lights)

Now when I get off in the sand and go up a few hills the light for the temp comes on after about 10 minutes.

If I lay off the throttle it goes off.

If I put it back in 2h it goes off.

Not sure about 4L because I havent gotten that far yet.

I have a new radiator the previous owner just installed a month before I purchased the truck.

Now here is an interesting observation. When I bought it I drove it around and then let it cool down and checked the fluids. The coolant looked fine.

BUT then after I got home and took it out and the light came on in 4h I let it cool and checked again and there was brown crud in the radiator. I flushed it over and over again with straight water and the crud has gone away and it is now pretty clean.

Still experiencing the problem though.

This is my first post/thread here so I hope in the future Ill be able to contribute myself instead of just asking for help.

 

[winterbeater]

No problem posting questions. You'll learn a lot more by searching topics. Overheating is a big one. The first thing I'd do is to get a temperature gage. This will be very hard to track with a light, and especially if you use your Jeep offroad, you may need to deal with more heat issues. Topics to read up on thru search:
1.) Testing your engine driven viscous fan clutch. Sometimes these don't engage.
2.) Testing your electric fan. (fan, relay, temperature sender)
3.) Pressure cap issues. Leaking cap allows boiling at a lower temperature.
4.) Using antifreeze. From your post, I can't tell if you may be running straight water. Must be nice to live in Florida, but you may need the extra cooling ability of 50/50 antifreeze.

Good luck. Try to get a gage. Read up on checking your fan operation.aperwork

 

[chrisvv]

Thanks! I meant to mention that I have spent the last week searching this forum and no luck.

1.) Testing your engine driven viscous fan clutch. Sometimes these don't engage.
2.) Testing your electric fan. (fan, relay, temperature sender)
3.) Pressure cap issues. Leaking cap allows boiling at a lower temperature.
4.) Using antifreeze. From your post, I can't tell if you may be running straight water. Must be nice to live in Florida, but you may need the extra cooling ability of 50/50 antifreeze.

1)Yes is is engaging and i've check the clutch and all seems fine.
2)New cap from dealership didnt help.
3)even though I am in florida I still run 50/50

 

[96xjeeper]

If you have not done so remove the stupid fire blanket under the hood. You can also remove the rubber gasket on the top of the hood. I did both of these as well as spaced my hood about 1/4" and cut hood vents and I cut about 1" off the rear corners only to make space for CB Coax but it does assist in venting heat. First time I wheeled my jeep it ran hot as crap and last time I wheeled it she never went above 210* I also have a 180* TStat to install before summer. I plan on doing a pretty extensive flush and changeing the TStat.

All the above should keep under hood temps down but it's better to figure out your problem to begin with

 

[joe_peters]

x2 on all of the above.

ALL of the xj cooling systems are, IMHO, BARELY ADEQUATE for normal city/hwy conditions.

Little punk radiators, nightmarish plumbing, weak fans.

IF everything is 100% OEM you should consider a few upgrades for anything more than driving on unpaved forest roads.

HD fan clutch, upgrade or add efan and add an command toggle switch for the efan would be the first things to do.

Down the road, when its due for another new radiator get a 2- or 3-core metal tank unit.

 

[ChevelleSSLS6]

http://www.ffdynamics.com/jeepradB1.html

 

[logdog]

You NEED a tranny cooler. Or at least a manual switch for the electric fan.

 

[scottmcneal]

T-stat working right? It is new right

 

[logdog]

T-stat should be 195 degree, and from the dealership. Theirs have a small valve on the top side to help bleed out any air. Your engine is designed to run between 190 and 217...iirc.

 

[chrisvv]

Okay so am I to assume that there is a good chance that I do not have a problem other than the OEM setup is inadequate for off road use?

What I' asking is, should I just stop going through the cooling system piece by piece and start upgrading to some heavy duty fans and away better than stock radiator...

Considering that everyday use everything seems fine.

 

[tupton]

I would start with a simple radiator flush. You'd be surprised how nasty they can get.

 

[96xjeeper]

I'd say yes there is no issue other than no air flow at crawling speed. Add an electric fan switch (I am in the process to adding a command switch to my AC Fan) and do the stuff I mentioned above. My mods keeps me running right at 200* on the roads and 210* off the road

When everyone say Tranny cooler you mean an additional Tranny cooler inline besides the one already part of the radiator? I have an Auto

 

[techno1154]

You said you are using a new radiator. That is good. You also said when you flush the cooling system, the coolant was very rusty. This could be a tell-tale sign that some problems could carry over into the new radiator.

My first XJ had a neglected cooling system. I flushed the system and replaced the radiator with a new one. What I did not anticipate was that I also loosened the rust scales inside the engine block which made its way into the radiator and blocked more than half the tubes.

I chased a cooling/over heating problem for months until I did a simple touch diagnosis. Yea, the top of the radiator was at the point of over heating while the bottom was cold.

Just one more thing to look at. I will add to the above responders, get a guage cluster. You will be happy you did.

 

[altierior]

all of my overheating problems were solved with the simple addition of the electric fan switch. when off, the fan operates normally, turns on and off as called for. when the switch is on, the fan stay on.

 

[winterbeater]

One strange thing comes up upon re-reading. You only seem to overheat in 4WD. Possibly your front axle has high turning resistance. You could jack up the front and check for turning resistance (with tcase in 2WD). Driving on a level dirt road in 2WD and you are good, but putting it in 4WD on same road and overheating shows excess resistance in the front.

 

[techno1154]

One strange thing comes up upon re-reading. You only seem to overheat in 4WD. Possibly your front axle has high turning resistance. You could jack up the front and check for turning resistance (with tcase in 2WD). Driving on a level dirt road in 2WD and you are good, but putting it in 4WD on same road and overheating shows excess resistance in the front.

I thought of that but I don't see how that could be an issue. :dunno: The OEM D30 always turns the gears and drive shaft when the XJ is moving exerting some load on the engine. Engageing the 4WD forces the front wheels to be part of the drive system instead of being along for the ride as they are when in 2WD. Maybe the problem is the transfer case??? I doubt that.

A partially internal blocked radiator, low speed resulting in little air flow and probably in a low gear as well are the only things I can think of. :doh:

 

[winterbeater]

But IF you go down the dirt road at the same speed and 2WD OK, 4WD overheat, it's telling you something. But you're right in that it would make more sense for it to be the tcase. But in the front end, the loads ARE going in a different direction. If something like that was wrong, you would think it would make a bad noise too.

 

[chrisvv]

One strange thing comes up upon re-reading. You only seem to overheat in 4WD. Possibly your front axle has high turning resistance. You could jack up the front and check for turning resistance (with tcase in 2WD). Driving on a level dirt road in 2WD and you are good, but putting it in 4WD on same road and overheating shows excess resistance in the front.

I dont think this is the problem but I will check. So how do I check this?

The other day I went in and out of a local sand pit that was pretty harsh to get out of. I ran the heat and I had no problem. heat light stayed off the whole time.

 

[winterbeater]

Jack up the front end. With the transfer case in neutral turn the drive shaft to feel is it turns pretty easy or not. Probably only one wheel will spin at first. Lock that one up with a block or log, and try tunning again.

 

[chrisvv]

Jack up the front end. With the transfer case in neutral turn the drive shaft to feel is it turns pretty easy or not. Probably only one wheel will spin at first. Lock that one up with a block or log, and try tunning again.

ill try this in the morning.