Here we go again... radiators

I've had the XJ for 10 years. I've had overheating problems for 10 years. I've spent thousands, yes, thousands of dollars on the issue.

Was fixed with a CSF 3 row and higher flow fans. Capacity issue.

Can't leave enough alone, I now have a stroker from a buddy's XJ. I now have overheating problems again (assuming it's due to the larger displacement).

It'll overheat on the interstate as well. (this is new). I even swapped in his CSF that he had no problems with overheating. Only difference is I have an a/c condenser and he didn't. I'm not ready to give up the a/c.

Thinking about 2 options.

1) Cheap route.

With all the frame bracing I've done, I no longer need the front cross member that the radiator sits on. I can cut this out. Find some larger radiator and Frankenstein that in. Downsides is the time to do this (it's wheeling season) and I'll have to come up with bash protection.

2) Not cheap route.

Griffin.

I've had so many different radiators, I'm tired of effing with it. I've had aluminum 1-1/2" wide that did no better. Multiple 2 and 3 rows.

Idears?

I am also curious as to why you are having so many problems. In three different jeeps I have run a two row and three row CSF radiator with no problems. Stock fans, stock water pump, and a 195 thermostat. When playing hard the temp gets to 210 and the e-fan kicks in and the temp does not hardly climb further from 210. Even a good friend with a 4.7 stroker has the stock cooling system and has not one problem with overheating.

Which temp thermostat are you running? What is the fan setup you are using?

What water pump are you using?

I've done every different set up you can think of. Different pumps. Different t-stats. Presently there's a high flow pump and t-stat. I've also tried throttling coolant flow down. It's all verified with an IR gun. Again, I've fought this for 10 years.

Since it's now overheating on the interstate at 70mph, it's not an airflow issue. Actually the transmission helps cool it down (once locked in, the outgoing fluid temp is 140-160F and you can watch it cool off the engine).

My trail ready weight is 6,000lbs, and the stroker should be pushing close to 260hp. Open up the stroker to play and the temp needle responds.

Sounds like your A/C condensor is plugged full of crap and you're still having an air flow problem. The parts themselves should not be a problem. You can't be that different from everyone else. Think of stuff that is not normal parts, the normal parts should be OK.

If you want to talk about a Griffin radiator, hold up a week or so. We're in the middle of getting two of them for the Petty Cash road race XJ and the Petty Cash/Team Ultra4 XJ. One will be installed in the road race car this week for the race at Sears Point next weekend. Griffin doesn't make an exact fit XJ radiator, but they have one on the shelf that is very close, only 1.5" off, but it doesn't have the two mounting posts on the bottom.

What gears are you running? When I went from 3.07's to 4.10's my overheating problems magically went away

Are you ruuning an auto or stick? if it's an auto get a trans cooler, I put one in and it lowered my temps a tad. but I would start with making sure you AC condensor isn't plugged

IIRC, overheating at higher speeds is at least partially a mech. fan clutch issue?

It sounds like you have checked/rechecked and replaced everything minus the Heater Core Valve.

Have you checked the coolant return flow from the heater core flowing back into the water pump/engine block? If that valve is plugged or restricted it could be part of the problem.

The link below might help you find and check it out.

http://www.naxja.org/forum/showthread.php?t=1080334

Isn't there a AC condensor that restricts the flow less then another? I thought I read that the 00-01 was less restrictive then the older ones. I could be completly wrong though.

Sorry guys. I didn't give you a good problem description.

It feels like a capacity issue. If excess heat gets in the system, it can't get rid of it.

If I'm on the trail... life is fine until 80+F outside and a couple full throttle uphill attacks. Once this heat gets into the system, it can't shake it off. I grab a sweat towel and turn on the heater full blast and it'll catch back up (w/o doors so it's not that bad).

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.

Best help is to have a 185F t-stat and have the fans rocking the whole time to keep the heat out.. if it gets to 215F under load, it'll take off until I either turn off the a/c or kick on the heater.

Again. Sorry.

I have replaced the heater core valve too.

I talked to a guy from Griffin and he said the 600hp 2 core unit was more or less a straight bolt in, at the worst I may have to trim some of the plastic on the shroud... Guess he was just being a sales dude?

I'm not feeling like messing with Frankensteining it. Looking for a radiator with more capacity. I know that 3 row copper and single row 1-1/2" aluminum won't do the job..

And you know your condenser isn't plugged up with mud or bugs or something?

I know you have a problem, but tons of other people have strokers with no cooling issues with stock cooling systems with upgraded radiators. However, in our Ultra4 XJ with a VERY potent stroker we're going to a bigger Griffin radiator. If I remember correctly the radiator that will fit is 1.5" wider than the XJ radiator, which should fit OK. Just have to figure out mounting.

http://www.quadratec.com/products/product_search.php?mn=Griffin+Radiator+%26+Thermal+Products&cn=Jeep+Cooling+System&c=65


These aren't direct fit Griffin Radiators?

Option one ... for a fix ....

Increased radiator core surface for cooling ... and an increased liquid capacity.

All the other stuff like fan swaps, pumps, whatever ..... are just band aid fixes ..... as are the hood, hinge spacers, low eth-gly ratio mix and better fanclutch I use ... to maximise the efficiency of the baby radiator.

robs said:

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.

Click to expand...

This line is telling, and I'm with Goatman on this one. First guess is that you don't have enough airflow through the radiator. On the highway you don't need a fan and should have more than enough cooling.

The condensor could be plugged like Goatman said. Or there could be a problem with air leaving the radiator: splash guards or something not letting the air out of the engine compartment.

Pop the hood at idle when it's hot. Is the air blown by the fans hot? If not it isn't pulling the heat out.

6000 lbs wow. I would get an external transmission cooler and put it behind the bumper, or someplace not in front of the radiator. Especially since you say once the trans is locked it cools down a bit. What gears are you running?

Have you checked the clutch fan to make sure it is unlocking properly? What do you have for a front bumper, lights, winch, anything blocking air in the front? Is the radiator cap holding pressure?

I can see through the condenser when the radiator is out... don't think it's a problem.

Airflow seams fine from the fans... I've got a huge cooler on the tranny and the power steering... I've also just purchased a 10,000 lb Warn winch that I need to figure out how to mount up...

Nothing really now in front of the radiator... Have had multiple fan clutches.. Rocking 1 Tons and 37s with 4.56s...Different radiators and caps...

Ahh, you have leaf springs up front, no wonder you're overheating.

With big heavy axles, larger 37's, and 4.56's you do probably need a bigger radiator. However, my old XJ (still driven regularly on the street) has a healthy stroker, D44/D60, and 37's and it never gets close to getting hot. It has 5.13's.

Does your torque converter lock up? Do you know for sure it's locking up?

blubullett said:

http://www.quadratec.com/products/product_search.php?mn=Griffin+Radiator+%26+Thermal+Products&cn=Jeep+Cooling+System&c=65


These aren't direct fit Griffin Radiators?

Click to expand...

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.

Damn them leaf springs. I knew it.

Torque converter locks. I've got a gauge on outgoing temp, and it'll drop to 140-160F once locked in.

Other than Griffin, who makes larger capacity radiators?