If your like me and have a cooling system that has the plastic bottle as your over flow tank and the fill spot for coolent AND it keeps breaking due to over heating I found A FIX!!! I had the great idea of putting a new 3 core radiator in and replacing the plastic bottle with a steel box that has a legit radiator cap on it. It has fixed the problem of over heating and has given my jeep more HP just from staying cooler. hope this idea will help if you have the same problem.

 

My sister has a 90- Cherokee I just got a 90 from her as well. About 5 years ago she started having overheating problems on hers. I bought a radiator from a 91 and put in there and did away with the closed system. The 91 radiator has a radiator cap on it. I just finished doing this same swap to my 90. I still need to fix an overflow bottle.
Can't figure why Jeep every thought the closed type system would be better.
clint

 

have fun with that, i build a replacement over flow that im getting ready to built it up. i all took my thermostat out and replaced it with a fail safe that is rated for 180 just doing that it runs cooler

 

heres my solution to that darned bottle: https://www.cherokeeforum.com/f58/ho...-delete-38204/
but it actually turns the closed system to an open system without changing the radiator.