early 4.0 cooling system solution

ok, this is the first i've heard of this done, and i just did it on my 89 4.0 and it works flawlessly as long as the plumbing all holds pressure. you need..

- coolant bottle from a corvette (i'll get PN later)
- some adapters
- a crap load of diff size hoses
- a lot of tape and/or hose clamps
- radiator cap

its really quite simple, the corvette bottle has 4 tubes coming off of it. just connect the hose coming off the bottom of the stock pressure bottle to the bottom tube on the corvette bottle. then connect the hose coming off the top of the stock pressure bottle, to the small tube that is 2nd down from the top on the vette bottle. then connect the remaining two open tubes together via some creative plumbing, slap a radiator cap on the top and you're all set. mine runs at 210* without the fan on and stays there no matter what i'm doing. heres a picture to explain it better, i'll get some pictures on here when it stops the downpour...



total cost of swap was a little under 50 bux with everything.

What year's on the 'Vette........and what did you gain? More capacity?

Looks like he essentially gained a radiator cap. A number of GM cars use similar bottles. CheapXJ (www.cheapxj.com) did the same thing using a bottle from a junkyard Pontiac, for considerably less than 50 bucks. (Hey, gotta live up to his name, right?)

not sure of years on the vette, i can ask my buddy who is a vette master tech, but basically, yea i gained a radiator cap and don't ahve to deal with that crappy plastic cap that jeep used which never held pressure.

I solved my leaky cap problem with a Volvo cap, part # 33051 (CarQuest). It is a much better quality cap, and has a higher pressure capacity (than a good Jeep cap, if you can find one). I got the recommendation and the part number from a tech at the Jeep dealership. I've had so many bad caps....the only persistant problem I've ever had with the closed cooling system on my '88.

Yeah, I never thought about that with the Volvos. I had a Volvo 940 Turbo that used a closed system and I never had one cooling problem out of it. Its a very well designed system.

yeah i could never get that crappy jeep cap to hold pressure, and i have a buddy with a 89 also and he went through like 5 or 6 different caps before he found one that was good. with this vette bottle, i don't even have to use the elec fan unless i want to keep it REALLY cool, it runs at 210 w/o it.

anyone ever get that part number? im having some cooling probs and i want to upgrade to this.

i'll have it ina little bit, waiting on my buddy to call back

chevy PN 10157994, it costs me about 30 bux or so but i got it through my buddy that works there so i'm not sure of cost.

I had a radiator shop make an in-line radiator cap for the upper rad hose. simply cut the upper rad hose where it runs between the a/c compressor and the valve cover and install it there.

I then took the two hoses that ran into the OEM coolant bottle and connected them together, plugged the top port on the bottle, and ran the bottom port to the overflow nipple on the new rad cap.
I leave the OEM cap a little loose and the OEM bottle is now a non-pressure recovery tank.
The beauty of this is that the system is self-bleeding as the cap is now the highest point in the cooling system.

I have had no overheats, and the system stays under 200*

i did mine with the pontiac bottle.. paid 3 bucks for it.

thanks cheap xj.

well, ain't you special! j/k i just really wanted you all to see my super dooper specialized power drawing that i spent so much time on

jeepxjga said:

well, ain't you special! j/k i just really wanted you all to see my super dooper specialized power drawing that i spent so much time on

Click to expand...

ya but now you can get a corvette embolem and stick on your cherokee..

cooled by corvette