Xj88

Someone help with this...xj over heats at idle...but when its going 20+ mph it stays at normal temp...it takes about 5 mind at idle to get excessively warm...where should I start with this? There is no way to get to a top radiator cap cause of the metal bezel on the jeep...coolant is dirty but doesn't have oil in it...just kinda old looking...the one fan works and the other cuts on when heat/ac is on...the hose from the bottom of the resevor is swollen and cracked...id replace it but one end has some metal fitting that goes onto another hose and im not familiar with how to remove it...thermostat was replaced a year ago...where should I start with this and any guesses at what it could be?

Modestmike

Fan clutch....worn out impellers on the water pump...blocked/clogged radiator.

excess650

Your cooling system and temperature sound pretty normal. The early XJs were RENIX era and had the radiator and coolant bottle as described. Drain the radiator by removing the lower hose. It sounds like the hoses need replaced, system flushed, and new coolant added.

The electric fan will turn on with the air conditioning or when the sending unit reaches just below 220*.

Check the fan clutch and see if it has moderate tension when cold and more when hot. If it seems the same cold and hot, its time for a replacement.

Xj88

Ok...im taking it your referring to the fan that cuts on at high temps? What all hoses should I plan on replacing other than top and bottom rad hoses?

mudfrog

As stated check your fan clutch.. I just replaced mine as it was doing the same thing.

Xj88

Any idea of where to find a write up?? How much did you spend on it?

rompnXJ

mine was doing the same thing.. if i let it idle for any longer than 4-5 minutes, itd overheat; this was about a month after a new radiator and a coolant flush.

replaced the water pump & thermostat, solved that problem and now i can idle it all day if i want. the old water pump looked fine, so im betting the thermostat was my problem. the thermostat is cheap & easy to replace so id recommend starting there. it may only be a year old but it could still have gone bad

Xj88

Well it was doing it before I replaced the tstat...how much ia a water pump and how hard is it to install?

Slick761

Water pumps are cheap cheap. Install not bad if you can drain and refill your system.

Xj88

Any idea on a write up??

Slick761

... well its not too difficult. Drain the system, take off the shroud and fan and belt and pulley and anything else that might be in the way and Unbolt the pump. When you put it back together I recommend water pump and thermostat rtv.I know Permatex makes it.

Xj88

Ok...if you find anyone finds a write up let me know...Ill end up royally jacking something up without a good write up haha

Slick761

Lol understandable... do you have any sort of manual? Haynes and chilton are cheap and get the job done.

Xj88

Yeah...ill head to auto zone and pick one up...had one but when I went spotless it poured rain and before I threw my tarp on it was sitting in my seat and got drenched