XJ Cooling Help

[alexfm]

IM sure this thread topic has pooped up before, so forgive the repetition, Im just a little too lazy to search. :sombrero:

Anywho, to my original train of thought. Does anyone have any tips or tricks to improve an XJ's cooling system? I've done everything I can think of, except run a bypass switch to the electric fan, which Im hoping to do soon.

Since Im sure they'll come up, the specs are as follows:

1995 XJ SE
4.0L HO
AX-15
215K miles.


Any help will be greatly appreciated.

Alex.

 

[DaJudge]

IM sure this thread topic has pooped up before, so forgive the repetition, Im just a little too lazy to search. :sombrero:

Anywho, to my original train of thought. Does anyone have any tips or tricks to improve an XJ's cooling system? I've done everything I can think of, except run a bypass switch to the electric fan, which Im hoping to do soon.

Since Im sure they'll come up, the specs are as follows:

1995 XJ SE
4.0L HO
AX-15
215K miles.


Any help will be greatly appreciated.

Alex.

What have you done to it?

 

[Topgun514]

are you looking for things like hood louvers, placement of louvers (because depending on where they go they make a difference) Cooling styles, radiators?

 

[MuckSavage]

How hot is it running. My XJ's temp guage would creep up, so replaced pretty much the entire cooling system. (Rad, water pump, T-stat, fan clutch, flush, etc.) After that, i still had the problem. Turns out, my guage was reading about 20 degrees high. Verified this via use of a hand-held infrared thermometer.

If i had to upgrade, I'd probably go with an Active Cooling Products rad, and possibly a cowl induction hood (I prefer the looks over the louvers, not sure if it's as effective).

 

[BEVAN]

lets see...I have a 93 XJ with 220k...I am removing the taurus (2500-4500cfm) fan and re-installing the mech fan....with the 97-98 ZJ fan clutch.
I am also installing a 10 blade fan from a 00 XJ and have wired a derale fan controler to cut it on...

The ZJ fan clutch part # 272310 -From NAPA (this is the best one)

If this does not help...you prob need repairs.

I also have hood vents...

 

[xj joey]

Guy in my Jeep club stacked some washers under the hood hinges to make a cheap cowl hood.

 

[Hill Bill E.]

Guy in my Jeep club stacked some washers under the hood hinges to make a cheap cowl hood.

Seen that done, and it works.

But if the temp is getting above 210-215 on that year of XJ, it needs something done.

Chances are, the rad is plugged, or possibly the block is full of scale.

Has there been any stop leak put in it? Bars-Leak is probably the worst stuff.

Yeah, it stops the leak, but also can plug the rad and heater core, or slow the flow enough to overheat.

Ended up pulling my buddy Daves rad last April, on the way to Moab.

His XJ is a '99, and the rad was only 2 years old. (from some insurance work done on it)

When we pulled it, the little Bars Leak 'brown honey balls' were still floating around in it.

 

[alexfm]

What have you done to it?

All I've done is replace the thermostat, and the thermostat housing gasket, and add coolant here and there when it gets low. The previous owner replaced the radiator just before I bought it.

 

[alexfm]

How hot is it running. My XJ's temp guage would creep up, so replaced pretty much the entire cooling system. (Rad, water pump, T-stat, fan clutch, flush, etc.) After that, i still had the problem. Turns out, my guage was reading about 20 degrees high. Verified this via use of a hand-held infrared thermometer.

If i had to upgrade, I'd probably go with an Active Cooling Products rad, and possibly a cowl induction hood (I prefer the looks over the louvers, not sure if it's as effective).

From looking at the stock water temp. gauge, I'd estimate maybe 240. If im just idling at a red light, or trolling a parking lot looking for a spot, it will usually end up sitting on the little white line right before getting into the red on the gauge.

 

[alexfm]

Seen that done, and it works.

But if the temp is getting above 210-215 on that year of XJ, it needs something done.

Chances are, the rad is plugged, or possibly the block is full of scale.

Has there been any stop leak put in it? Bars-Leak is probably the worst stuff.

Yeah, it stops the leak, but also can plug the rad and heater core, or slow the flow enough to overheat.

Ended up pulling my buddy Daves rad last April, on the way to Moab.

His XJ is a '99, and the rad was only 2 years old. (from some insurance work done on it)

When we pulled it, the little Bars Leak 'brown honey balls' were still floating around in it.

I dont know about the stop leak, but I doubt there is any in there. When I bought it, the PO had just replaced the radiator, so its about a year old now.

 

[alexfm]

lets see...I have a 93 XJ with 220k...I am removing the taurus (2500-4500cfm) fan and re-installing the mech fan....with the 97-98 ZJ fan clutch.
I am also installing a 10 blade fan from a 00 XJ and have wired a derale fan controler to cut it on...

The ZJ fan clutch part # 272310 -From NAPA (this is the best one)

If this does not help...you prob need repairs.

I also have hood vents...

COuld you give me some more info on this? Thats something Im willing to try as well.

 

[BEVAN]

COuld you give me some more info on this? Thats something Im willing to try as well.

Yep,

For starters you want to make sure your motor mounts are good...Because when you swap in the ZJ clutch (Nappa part #272310) it is longer than the OE XJ clutch assy, Therefore closer to the radiator. Like I said in the first post I also have a Derale adjustable fan control from Summit (Derale part #16759) with an overide switch. That is wired up to a 2000 XJ 10 blade E-fan, They flow better.

I had the Taurus fan and the factory 5 blade AUX fan hooked to dual Derale controlers before...I switched it to the above setup because the previous setup was way overkill, Even without having the high speed hooked up. The taurus fan also pulled lots of power, with the alternator relocation as seen here :http://www.naxja.org/forum/showthread.php?t=1016319 -It made it impossable for me to fit a larger higher CCA battery from a newer XJ...So I switched back.

I have tested the new set up on my 01 XJ and it works perfect-O

 

[ROKTAXI]

Most XJ owners have had, at one time or another, over heating issues. Some were problems with hwy speeds with A/C on others with slow speeds in trail conditions. The design of a wide radiator I've heard is not the preferred configuration. This may add to the problem but I don't know. There are MANY suggestions to consider. I have the Taurus fan setup and the 10 blade auxiliary on my '94 XJ. I also decided on a 3 core radiator. I also have hood vents. In the summer I run distilled water which actually helps a little. As for the Taurus drawing too much power, I upgraded my battery cables and ALL my ground straps and running a stock 90 amp alternator. Runs my 8500 Ramsey winch (pulled 6 vehicles up an obstacle with no problem) with no power restrictions.

Back to the over heating. If I were to do it over again, I would probably retain my stock fan set up but I also like the fact I can keep my fans on after the engine is shut off. After much info searching, I settled on a 3 core brass radiator. That made a big difference. I cleaned my A/C condenser and my trans cooler for better air flow. I'm guessing that those restrict air flow to some degree. Back flushing the radiator / block may also be a consideration as some of the passages in the head gasket are quite small.

To sum it up, it's not just one or two items, but IMHO, it's many things combined that make up the big picture.

 

[gasman]

so it only gets hot at low speeds? how is it on the hiway ?
do you have a/c, the rad may be new but if the a/c coil is plugged it aint gonna flow air, howz the water pump ? i had recently installed a 3 core rad from dpg and removed the ac coil, in town i rarely need the fan at all cuz it ran soo cool even in the summer months ,, my issue was on hiway speeds , i beileve it was caused mostly because my after market bumper completely changed the airflow, and combine that with the missing splash gaurd that everybody throws away,that is there to create that flow of air thru the engine bay
i was experimenting with some scrap sheet metal and made an air dam on the underside of the bumper, plus a new splash gaurd, and dropped my highway temps 10 degrees .

 

[Topgun514]

Can we talk about hood vents and locations too please, unless this is poaching but I think it could be pertain-ant. There is a lower pressure region on the hood closer to the windshield, a vent here is good a slow crawl speeds but at anything about 25, will suck air in and actually push back against the fan. Mounting too far in the front I have heard can also ruin things. Can we get a good location for NON crawl speeds?

ie. What vent location is best for ventilation of engine at speeds about 25mph, that takes air in and directs it in correct flow patterns