Here we go again... radiators

[jeeperjohn]

On the interstate it's OK until 80+F outside, and kick it down to 3rd gear climbing a hill with the a/c on... it gets this extra heat in the system and it can't get rid of it.

..

Forgive me if this was covered but if you are in 3rd gear climbing and if you have the tranny fluid going through the radiator, you need to put the shifter in 3rd to make the torque convertor lock up. When the tranny downshifts itself into 3rd, the torque convertor remains unlocked causing the tranny fluid to get very hot. If the fluid flows through the radiator, it passes that heat on to the coolant just before it goes back into the engine.

 

[Goatman]

Forgive me if this was covered but if you are in 3rd gear climbing and if you have the tranny fluid going through the radiator, you need to put the shifter in 3rd to make the torque convertor lock up. When the tranny downshifts itself into 3rd, the torque convertor remains unlocked causing the tranny fluid to get very hot. If the fluid flows through the radiator, it passes that heat on to the coolant just before it goes back into the engine.

Very good point. I missed the 3rd gear kick down comment.

 

[cal]

It appears that Griffin sells so few of those XJ direct fit radiators that they make them to order. They can help us get a radiator cheaper if we use one off the shelf that is very close, but slightly bigger.

I was quoted $500 for the "600 horsepower" XJ radiator at 4wheel parts just before KOH. They had it in stock.

They have a "400 horsepower" radiator for $400, but it wasn't in stock.

Edit: Those prices may have been wholesale, but the point remains.. they are out there, we just couldn't leave well enough alone with the race cars.

 

[blubullett]

Do you happen to know the part number for the off the shelf radiator that almost fits Goatman?

 

[cal]

http://www.4wheelparts.com/Heating-...518&t_pt=5111&t_pl=107269&t_pn=GTP5-591LB-FXX

 

[robs]

Went ahead and scored a 2 row 600 HP Griffin radiator from 4WD.COM... It hurt my credit card...

It is huge. Here it is compared to the 3 row CSF..

Biggest deal is getting the condenser lines to clear around the tank and moving the radiator mounts forward. I carefully bent the condenser lines... with 17 year old lines.. I was very careful..

The tranny cooler line is pretty low and with the connections I bought, I had to clearance the pan...

Boxed in the cut out so a rock kicked up by the front tire wouldn't hit the huge tank on the Griffin...

Cut the header (fiberglass cutting SUCKS.. use PPE)... the top let you move forward with the condenser...

Then cut and move forward the bottom mounts a good 3/4"...

Can get a full finger in between the fan clutch and the radiator... With the sold motor mounts.. this is fine..

Moving forward the top cross brace... have to clearance for the radiator mount...

Haven't put many miles on it yet.. So far.. so good.. Will post up results as I get a better feel for it..

 

[Talyn]

For what they charge for them you think they could make them fit better.

 

[Weasel]

Yeah if you don't want to move it forward you have to run electric fans. That's what I did on mine. They are nearly twice as thick as stock so it's no wonder they don't fit with out some work. Although I move mine forward 1" and am running electric fans.

 

[barillms]

I believe the overheating problems in our rigs are due to a few things:

1. Radiator is too short, it should be taller.
2. 210 is normal operating temp, Water boils at 212...
Even a SLIGHT boil introduces air bubbles into the system which therefore interferes with the water pumps ability to circulate fluid efficiently, plus air pockets will develop further making the ability to cool less efficient.
3. Traditional framed vehicles have openings on the sides of the engine bay which allows air to flow in & vent out.... helping to cool the engine compartment. Our unibody rigs have a sealed engine compartment... air doesn't readily flow in. It's like an oven.

I have 3 10" pusher fans. Puller fans can & will shut off because they have thermal shut off protection built in once the fan motor gets too hot inside the "Oven" so pushers are the way to go.

Hood vents are mandatory... More the better.

Check out Evan's Waterless coolant. It won't boil at 212, therefore no air bubbles in system. Therefore no inefficient carbonated coolant, therefore no inefficient cooling woes.

Maybe try thin weight Synthetic oil = less friction = less heat.

Try running your tranny thru a separate cooler.

I'm struggling with the same overheating problems.
The only other thing I can think of is the timing was advanced unintentionally when you built your stroker.

 

[whitexj98]

I believe the overheating problems in our rigs are due to a few things:

1. Radiator is too short, it should be taller.
2. 210 is normal operating temp, Water boils at 212...
Even a SLIGHT boil introduces air bubbles into the system which therefore interferes with the water pumps ability to circulate fluid efficiently, plus air pockets will develop further making the ability to cool less efficient.
3. Traditional framed vehicles have openings on the sides of the engine bay which allows air to flow in & vent out.... helping to cool the engine compartment. Our unibody rigs have a sealed engine compartment... air doesn't readily flow in. It's like an oven.

I have 3 10" pusher fans. Puller fans can & will shut off because they have thermal shut off protection built in once the fan motor gets too hot inside the "Oven" so pushers are the way to go.

Hood vents are mandatory... More the better.

Check out Evan's Waterless coolant. It won't boil at 212, therefore no air bubbles in system. Therefore no inefficient carbonated coolant, therefore no inefficient cooling woes.

Maybe try thin weight Synthetic oil = less friction = less heat.

Try running your tranny thru a separate cooler.

I'm struggling with the same overheating problems.
The only other thing I can think of is the timing was advanced unintentionally when you built your stroker.

It dosen't boil at 212 in a closed system radaitor, closer to 265. I still believe a well maintained OE system is one of the best...

 

[robs]

For what they charge for them you think they could make them fit better.

Fit is actually good.. they are just effin huge by the time you get two 1-1/4" rows..

Yeah if you don't want to move it forward you have to run electric fans. That's what I did on mine. They are nearly twice as thick as stock so it's no wonder they don't fit with out some work. Although I move mine forward 1" and am running electric fans.

I couldn't figure out how to make electric work. Simply wasn't enough room. I know Go Jeep removed the pulley for the mechanical clutch.. but his is RHD and has a different accessory belt... removing this pulley on our LHD looks to be problematic for enough fan belt friction on the alternator and crank pulley..

Please post some pics. I'd like to see how you solved this.. and will remove my mechanical (prefer to run electric)

 

[techno1154]

Went ahead and scored a 2 row 600 HP Griffin radiator from 4WD.COM... It hurt my credit card...

It is huge. Here it is compared to the 3 row CSF..

Especially that side to side comparison, that radiator is the most beautiful thing I have seen yet. That extra capacity would go a long way towards keeping high temperatures at bay.

From the reading of posts on the internet I understand that most of the overheating experienced on the XJ's happen as spikes; ie, the temperature suddenly/quickly shoot up to infinity. That my friend I will attribute to the fact that there is insufifient coolant capacity combined with air movement through the radiator and engine compartment. Yes, I know,... like a religious pilgrimage to Meca one is required to do a complete cooling system over haul every year without fail. Well, it appear that most XJ owners including myself do not do it. It is also my feeling that removing the air dam under the bumper and the fiber mat under the engine changes the air flow through the radiator negatively. No, I do not have sicientific data to back that up I am basing my opinion on other vehicles on the road.

I am sure that the larger more efficient radiator not the miniature 3 core radiator will be one of the best mod you did for the 4.0L

And OH! By the way, the Toyota pickup with a 22RE engine that I DD and the Hyundai Elantra that my wife drive have a larger cooling system than my XJ.

 

[barillms]

Not boils over... Water boils at 212. It's a fact....

 

[sidewaysstarion]

Not boils over... Water boils at 212. It's a fact....

but the whole point of keeping the coolant under pressure is it raises it's boiling point.:wave1:

 

[Lurch]

Plus the glycol in the antifreeze raises the boiling point.

 

[rstarch345]

but the whole point of keeping the coolant under pressure is it raises it's boiling point.:wave1:

That is correct http://installer.aed-inc.com:8191/Stant Technical Info/TempTalkRadCap_4.htm

 

[Pelican]

To put it another way, pure water in an unpressurized container boils at 212* at sea level. Change any of these parameters and the boiling point rises or falls.

 

[whitexj98]

Not boils over... Water boils at 212. It's a fact....

And its also a fact that for every psi of pressure the system is under it will raise the boiling point by 3 degress..

 

[robs]

Wasn't happy with how close the fan clutch is to the radiator... I can get a full finger in between.. but not enough..

Found a telephone pole and 4low and torqued it... came stupidly close to hitting the radiator.. (The "OT" is backward for the "TON" on my plate)...

Looking at the motor mounts I made, I used LCA bushings and here's the one for my friend's XJ that had the stroker in it I've got now.. Notice how it's moved forward by a LOT...

Based on this, I made up some washers and cut the forward motion in 1/2... This should bet the same for some aftermarket mounts as well...

 

[stewie]

Not boils over... Water boils at 212. It's a fact....

water boils at 212*F at 14.7 psia or 0 psig (sea level) change those figures and the boiling point changes. Increase the pressure and the boiling point goes up. Decrease those pressures and the boiling point goes down.

by changing the pressure of a system I can make water boil at 33*f or at 400+*F. Its all about pressure man. And to really trip you out I can make steam dry (superheated steam).