Hey guys, I have the 90 4.0 with the closed system that I am planning on swapping to the open style from 91 and newer..


So far here is my parts lists...

91 style radiator, 91 upper radiator hose, 6 ft of heater hose (various sizes), clamps, coolant, 91 style heater valve..... What else do I need???

Also I am wondering how you guys that have done this swap,, routed your heater valve from the coolant overflow reservoir to the pump?? I have read several DIY's, but no pics... I was hoping to make this as painless as possible and quick so if you have some tips, tricks, points to avoid, or just something at all please feel free to add!!!



THanks guys!!


Josh


P.S. I have a brand new 90 style heater valve that I just installed that will no longer be needed.. If you need it, 5 bucks gets it!

 

I did the swap to my '89.
I switched my thermostat housing for one that had a temp sensor in it.
You will also need a new radiator cap, an overflow bottle, and some hose to attach to the overflow bottle.
I made my own overflow bottle from a plastic Pepsi bottle...not much room in there for much else.
I recommend doing a major flush of the cooling system beforehand..no use in getting your new rad full of crud..
I wanted to do the job only once, so i went with all new parts.
I used a new Mopar radiator I found on eBay, but you might consider one of the 3-row radiators available...I'm sure others will chime in about them.
While you're in there, it would be a great time to replace the water pump as well.
There is a good write-up on one of the other forums about the swap that had a diagram and photos,as well as all the part numbers, but I can't remember which forum...sorry!
(It was about 3 years ago...ancient history, as far as my memory goes...)
Hope this helps!

 

autozone radiator -


there is a threaded hole for the sensor on the new one
-same place as the old style is.


Tou have to bend the transmission line (auto) a little to fit around the fan

 

i used a ball valve to for the heater core - lower hose
http://www.lowes.com/lowes/lkn?actio...BXB&lpage=none

 

If you look in my photo album I have all the pics from under my hood. You can see where I moved my coil to and relays and still used the 91+ resevoir. I would post but my work computer is way to slow to try. You have all the parts you should need.

 

Here's how I modified the heater and cooling systms on my 88.

The heater valve is for a 80 Dodge D-150 Pickup with 225 slant six (just to get you a part number). The control cable is a universal choke cable and the old pressure bottle cap has the pressure valve cut out and the bottle has been tapped for barbed fittings. The filler is a 1 1/4" Moroso part from a Speedway catalog with a AutoZone 16 psi cap.

No leaks, no overheating, and most of the cost was in fittings, clamps and the filler. I run just the clutch fan and no shrouds, but it's not summer in south central CO yet . . . . .

Budd

 

You guys may laugh but I am actually going to be using an empty Rockstar Energy can as my overflow.

When I get the time/motivation, i'll post pics of the finished deal.


Josh

 

okay okay okay, I just found my other thread (this one)

So if you are (or have read) the other thread I am having some issues.

I'll try and see if I can merge the thread...

Josh

 

alright now,,,

I went ahead and pulled the water pump,.. MAN! the timing cover is certainly leaking!!! I wonder if I should go ahead and change it as well???


**Adds another item of the to do list on the cherokee...

Okay so tomorrow I am going to check this out at work and see what is the dealio...


Hopefully I should have this thing done by the end of the week.. Gotta go take care of school stuff tomorrow and clean the house..

Apparently my wife thinks the house is more important that the jeep?@?@?!!?!?!??!



Josh

 

This is the write up I used, it's pretty well detailed. HTH!!

http://jeephorizons.com/tech/xj_cooling.html