warrior36738

Hi guys

I have the privilege of owning an xj 1999 4.0 ax15 and being a member of this wonderful forum.

My jeep has this strange issue in a couple of days.It starts getting overheated when idle the temperature crosses the half mark in no time (in a traffic light or any other place) but when I drive the temp starts coming down.

First I flushed the radiator still the same case than removed the head and did all the gasket and other essential change.When this issue continued I finally changed the radiator and installed two extra fans.

But still it gets hot and is still the same.I checked the waterpump its working fine.Please help me.

tech

It sounds like the fan clutch is bad and not pulling enough when sitting still . the electric fan should kick in about 215-220 .

warrior36738

Al right I will have the first check this morning.Hope this works

moparado

Welcome to the XJ hot weather idle overheating club!
How hot does it get? Did you verify the temp. with thermal heat gun?

First and foremost does the efan ever turn on when idling?
If it doesn't turn on i'd suspect the coolant temp. sensor or something going on with the efan itself.
If the efan does turn on at hot idle, your're in for a parts trial and error.

fan clutch as mentioned,
water pump, how do you know its good?
hoses, check to see if they are worn and collapsing
thermostat
clean the bugs and debris out of the radiator
internally clogged radiator, i'm on my 3rd and counting
on and on.

Only thing that works for me is manually turning on my efan when i see the temp approach or rise past 210 deg.

I wish you luck as i've been fighting this every dam Summer.
If you figure this out, let us know.

warrior36738

Thanks for the invite mate.

Coming to the things I did today changed the fan clutch and as soon I drove a few miles the hose pipe got busted.

I changed the radiator with a new one triple core and the water pump is fine cause i took it to a workshop and he said its fine.

The temperature I didnt checked with any equipment but it is far from any normal temperature.It gets hot to a point when the temperature gauge reached 3/4 in 10 minutes tops and when it runs it gets back to normal.I have installed two extra fans and I will checkmfor efan option too.

Thermostat or no thermostat i tried everything I will replace the hose pipe tomorrow and see what happens next

This is the first time my small predator has Just Emptied Every Pocket of my pants

moparado

Temp gauge reaches 3/4s of full scale in 10 min. sounds like something is definitely going on. The electric fan (efan) should be on at that temp.

From what you said, sounds like the efan is not turning on because its either broke or the coolant temp. sensor is out of calibration and needs replacement.
You really need to verify if the temp. gauge is reading accurately with an infrared thermal heat gun. Maybe you can borrow or rent one if you can't afford buying one.

I'd first verify that when the temp. gauge reads 3/4 full scale that the efan is on and running strong.

Cherojakee

If your idling in traffic and the temp starts going up, put it in neutral and give it a little gas. This should bring the temp down. What is the temp outside where you are at?

warrior36738

Even after all this the car is still the same.Tomorrow I am taking to a workshop to check Efan and cooling temp sensor.

As I had installed two extra fans to cool it down but to no avail this is still the same.

Yes I do the same as in neutral to bring the temp down.

The temperature here is around 45 degree Celsius but my other jeep is fine.Any ideas what else could go wrong

warrior36738

I just checked the Efan it's fine cause the other two fans are working along with it.The coolant from the reservoir gets spilled out due to excess heat.
What I do next????

moparado

What two other extra fans are you referring to? Aftermarket addons?
Did you remove the mechanical fan?
Can you post a picture of those two extra fans?

Cherojakee

45 degrees celsius = 113 Fahrenheit. That's darn hot. I would say your temp is in the normal range. It doesn't get that hot where I'm at, but my jeep does get above 210 on hot days. If there was an issue with your cooling system, your temp would spike and you would be overheating. You mentioned your other Jeep, which is probably not a Cherokee so it's not a good comparison. Here's a link to a good write up about XJ and cooling problems:http://www.ausjeepoffroad.com/forum/...d.php?t=103975

Basically, the Cherokee wasn't designed for the 4.0 and there is a lot of ambient heat under the hood. If your looking to move that hot air away from your engine, you may want to try hood louvers.

warrior36738

Yes the car gets overheated cause the reservoir tank spils all the coolant out of it plus all the hose pipe and radiator cap starts to make noise.I do have one more xj and a grand cherokee besides this.The other two are fine.

The temp snap which I just shared with you-guys is just when it starts it crosses and reaches three forth very easily.

They are after market addons.i didnt removed any mechanical fan all are intact plus i changed the fan clutch as well

Cherojakee

Ok gotcha. So the temp does spike when you idle. So the hoses have a lot of pressure and are hissing? Did you check the upper hose for pressure (wear a glove) while hot? If the pressure is low on upper hose it's probably your water pump. It may look good but the bearings may be bad. It sounds like that is the only part you didn't replace.

andrewmp6

210 is normal temp for the 4.0 they do run a little hotter then other engines.And you do live in a hot place so it might run a little hotter because of that.You can try adding some water wetter it will drop the temp a little bit.

moparado

Did you replace the radiator cap?
When you did the flush, did you properly burp the coolant system?