Originally Posted by 1991Jeep_Man
Ok, because I was doing some internet research and found something about parking nose end down and removing the coolant temp sending unit on the back of the head.. But it said this was for a closed system RENIX '88 Cherokee... Is my '91 a closed or open system? What's the difference?
91 is open system, the difference is the open uses a normal radiator with a cap, the closed uses a pressureized bottle with no cap on the radiator. Be sure when you fill the system and run it have your heat on so that the heater core gets filled. trs80's idea works well, or you could fill radiator with coolant let it set top off if needed, then start engine run with cap off wait till tstat opens then fill as needed, I repeat, have the heat on lots of people forget to do this.