Where Might it Be Leaking?

[Nick1994]

My grandfather's '96 Jeep Cherokee with the 4.0L was leaking yesterday. He drove it around and pulled in a parking lot and the temperature light came on indicating it was overheating (no needle gauge). He saw that there was coolant on the ground and he had it towed home. I looked at it today and the radiator is full and the overflow is about 1 1/2" low. I started it up and let it warm up and I can't see any leaks, but I did notice the plug for the radiator fan has a broken tab and came disconnected. I rigged up a way to hold it together.

It had brand new everything in the cooling system, and I mean everything.

The A/C was on and it was hot out. What could have been leaking? Can the radiator cap start leaking from the heat?

 

[exranger06]

Use a cooling system pressure tester on it. You should be able to spot it easily under pressure.

 

[Donald]

If the electric fan on my Jeep is not working it will overheat quickly in any kind of city traffic. You might not know it for awhile if the outside temps are low and you do not get into stop & go traffic.

 

[SwampSurvivor]

The Cherokees have a mechanical and an electric fan. If everything is truly working as expected and the electric fan failed and caused an overheat, the mechanical fan would be roaring.

I'd check the coolant elbow off of the water pump. Everyone forgets those.

Failure of the electric fan can certainly cause an overheat, though.

 

[Nick1994]

Originally Posted By: Miller88
The Cherokees have a mechanical and an electric fan. If everything is truly working as expected and the electric fan failed and caused an overheat, the mechanical fan would be roaring.

I'd check the coolant elbow off of the water pump. Everyone forgets those.

Failure of the electric fan can certainly cause an overheat, though.
Lol even the elbow is new. I'm going to go start it again and keep looking

 

[Donald]

Originally Posted By: Miller88
The Cherokees have a mechanical and an electric fan. If everything is truly working as expected and the electric fan failed and caused an overheat, the mechanical fan would be roaring.

I'd check the coolant elbow off of the water pump. Everyone forgets those.

Failure of the electric fan can certainly cause an overheat, though.


My 2001 Grand Cherokee only has an electric fan. I thought it was an electric or mechanical fan. Not both.

 

[SwampSurvivor]

Originally Posted By: Donald
Originally Posted By: Miller88
The Cherokees have a mechanical and an electric fan. If everything is truly working as expected and the electric fan failed and caused an overheat, the mechanical fan would be roaring.

I'd check the coolant elbow off of the water pump. Everyone forgets those.

Failure of the electric fan can certainly cause an overheat, though.


My 2001 Grand Cherokee only has an electric fan. I thought it was an electric or mechanical fan. Not both.


The grands have electric, mechanical or hydraulic.

XJ Cherokees have a side-by-side setup. On the passenger side is a traditional mechanical, clutch fan and on the drivers side is an electric.

Depending on the year, the electric fan will either/or come on at a certain temperature and when the AC is activated.


Edit: 4.0L XJs.

2.5L XJs have a one-wide setup like one would expect. Except if it is equipped with AC it has an electric fan in front of the mechanical fan, behind the radiator.

 

[Nick1994]

Originally Posted By: Miller88
Originally Posted By: Donald
Originally Posted By: Miller88
The Cherokees have a mechanical and an electric fan. If everything is truly working as expected and the electric fan failed and caused an overheat, the mechanical fan would be roaring.

I'd check the coolant elbow off of the water pump. Everyone forgets those.

Failure of the electric fan can certainly cause an overheat, though.


My 2001 Grand Cherokee only has an electric fan. I thought it was an electric or mechanical fan. Not both.
I did find a cracked exhaust manifold while I was under there

The grands have electric, mechanical or hydraulic.

XJ Cherokees have a side-by-side setup. On the passenger side is a traditional mechanical, clutch fan and on the drivers side is an electric.

Depending on the year, the electric fan will either/or come on at a certain temperature and when the AC is activated.


Edit: 4.0L XJs.

2.5L XJs have a one-wide setup like one would expect. Except if it is equipped with AC it has an electric fan in front of the mechanical fan, behind the radiator.

 

[MNgopher]

If you aren't quickly finding the leak, borrow a pressure tester from an autoparts store (I know O'Reilly's has them for loan for free witha credit card, guessing other stores will do the same type of loaner program). Guaranteed you will find your leak quickly if there is one.

If you don't find a leak that way, you may want to check the fan clutch,as the mechanical fan should have been roaring if the e-fan wasn't working. The E fan should turn on when you turn on the A/C. (Or if it gets hot enough - on my old Renix '88 Cherokee, that was 220+ on the temp guage)

 

[Oldmoparguy1]

Originally Posted By: Nick1994
My grandfather's '96 Jeep Cherokee with the 4.0L was leaking yesterday. He drove it around and pulled in a parking lot and the temperature light came on indicating it was overheating (no needle gauge). He saw that there was coolant on the ground and he had it towed home. I looked at it today and the radiator is full and the overflow is about 1 1/2" low. I started it up and let it warm up and I can't see any leaks, but I did notice the plug for the radiator fan has a broken tab and came disconnected. I rigged up a way to hold it together.

It had brand new everything in the cooling system, and I mean everything.

The A/C was on and it was hot out. What could have been leaking? Can the radiator cap start leaking from the heat?


The broken tab on the electric fan explains the overheating. What is the chance that he parked over the spot where someone else leaked A/F?

The A/C was on? How about the condensation drain from it?

 

[eljefino]

Tabs don't just break. They do get brittle with age. Someone was messing with the fan motor. Doesn't this tab have the little red "extra jam tab" to make really sure they don't come apart?