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Ultimate cooling


NAXJA Forum User
Fort Collins CO
I did a little digging with the search feature but didn't find much. I've recently swapped a V8 in my MJ and put the stock 4.0 cooling system back on temporarily. Now it's time to find a fix. The way this engine fits in it may as well be a 4.0, the clearances around the front are about the same.

So.. it looks like the stock radiator dimensions have more surface area than a conventional squarish radiator that could be made to fit. I've thought of notching the crossmember and dropping an aluminum rad in, but it can only be so wide without hitting the power steering box.

Is the BeCool stock dimensioned radiator considered the ultimate cooling solution for this chassis? I like the part, but not the price.. and if I cut out the xmember and drop in a generic aluminum, the fan fit will be a b1tch.
JJacobs said:

C-Rok has an aluminum unit of some sort in his 350 powered rig, it fits without the upper rad support or the head panel in place, I think he mounted it to tubing. Get some pics from him, and it will be clear.
Replacing the cross member with a little tubing wouldn't be hard, and the XJ radiator is pretty narrow (top to bottom). Someone awhile back had posted up that they had talked to an engineer at Camp Jeep who had worked on the XJ design, and he said that our radiators are questionable from the beginning because the body lines only allowed for a short height but wide radiator. He said it's hard to use the long length of the tubes since most of the cooling is done before the water reaches the ends of the tubes. A radiator with more tubes, but shorter tubes, would be better. This is probably the reason that ours cool fine when everything is working properly, but there is little margin for error if something in the sytem isn't working right.

I have my electric fan hard wired to the ignition. The thing rarely heats up past 160-170 even when run hard, but if I disconnect the fan relay it shoots up to 210 pretty quick in moderately warm weather driving around town, and will get hot if pushed, like going up a long hill.