99+ Open Cooling System Mod

Has anyone completely swapped in a 99+ cooling system onto closesd loop renix era system (88)? Through my searches I've seen several article about changing the heater control valve and some about deleting it etc. etc. I have a parts 99 that I can pull the entire system from and was wondering if there would be any issues.

99 Radiator
99 Hoses
99 T-stat
99 Water pump
99 overflow bottle

Are swapping all of these parts necessary? Do I need to change the water pump if its not having a problem?

Thanks,
Ron

rubiconron said:

Has anyone completely swapped in a 99+ cooling system onto closesd loop renix era system (88)? Through my searches I've seen several article about changing the heater control valve and some about deleting it etc. etc. I have a parts 99 that I can pull the entire system from and was wondering if there would be any issues.

99 Radiator
99 Hoses
99 T-stat
99 Water pump
99 overflow bottle

Are swapping all of these parts necessary? Do I need to change the water pump if its not having a problem?

Thanks,
Ron

Click to expand...

Ron,
If I were you, I would only use the radiator, hoses, and maybe overflow bottle. The water pump is not necessary unless yours seems old or worn, and the same goes for the thermostat. The heater hoses will get rid of your need for a valve since they will flow coolant directly into the core. Some say this is a bad thing, but I have done it to several Renix era XJs and it hasn't affected A/C performance in the least. I also feel by getting rid of that, you're eliminating the weakest link in the system. To use the 97+ heater hoses, you will have to screw a longer elbow with a 90* bend into the water pump outlet. This can be had off of any 91+ Cherokee or you can fab one up with brass or copper tubing. It's up to you, at that point, maybe you're better off just doing the water pump too, I'd just be tempted to leave it alone if it's not feeling too work by moving the pulley, etc. Good luck and let us know if you have any more questions.
-Collin

Damn Collin, I could not have said it better......well, maybe I could have J/K

Thanks for the replies guys!!!!

My 99 is about 250 miles away sooooo does anyone happen to have any under hood shots of the hoses and their routing.

Thanks,
Ron

There ya be...


If you decide to use a valve...did I mention I wouldn't?





If you decide to use the stock overflow bottle...I wouldn't, but did originally on one of mine...

you need to decide where to put the sending unit for the e-fan. In the HO it is in the thermostat housing.