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Overheating w/new componets

ttbomb334x4

NAXJA Forum User
Location
Columbus ga
I have had my xj for about a year now i am 16 just started driving it less than 4 months ago.Well it would over heat get into the 225 range almost in the red. I would cut it off it would boil over. WEll thtat would only happen every now and then. Well one night last week It did it once so I said i am going to get a new rad cap and se if that is my prolblem. Well went to the stealership. The new cap was a little diffrrent it didnt tighten up as good as the old one. Get to a friends house it didn boil over or overheat. He turned the cap it went everywhere. So i filled it back up drove a 20 min ride moslty highway home. It was fine 210 the whole way. So i pull up to a few red lights it gets up close to 235nd i pull in my driveway it goes everywhere. So the next day I get the radiator professionaly cleaned. new coolant with a produt caleed 40 below. New 180 deg thermostat. New upper and lower radiator hoses. New waterpump. It runas all day on the highway around 180 to 210 only gets to 210 if a am ihn town stop and go it will creep past that sometime. Well i say I got it all fixed get out on the trail and it goes up to 20 kinda fast i am in 4 lo it got almost to the red i blasted the heater and turned it off. A little coolant came out. I have a 4 inch lift 31's and i want to whhel. I csnt with this. On the highway and in town it does fine. I am thinking of ordering a new cap/bottle. Any help would be apperciated sorry for the typos overwrite is on and cant figure out how to get it off
 
sometimes, tstats can be DOA-you could always test and see what temperature it opens up at in hot water with a cooking thermometer of some kind. generally, there is little reason to get a 180 dehgree tstat in a cherokee, seeing as how (if i recall correctly) the factory specs them as running normally in between something like 180 and 225 degrees. i can't speak on the cap for certain, though i generally have not found the newer caps i get to be very loose. an old one that is a little tight could change the shape of the fill hole somewhat, but that's all i've got.

also, definately check the pressure bottle and cap if you are still running the closed system. that's an extremely common way to lose pressure on the 87-90 XJs.
 
I too had a similar problem, changed all the small stuff, and was still overheating, changed the rad...........and now I am running cool as can be, it was worth the $140 CDN ($100 US) for a new rad, hell now I can even wheel with the AC on, and its a simple removal/replace, had it done in 40 minutes
 
What year XJ do you have? If the rad is over 7 years old, pull it, throw it away, and get a new one. Now with what you stated in your story you are OK at highway speeds and around town, it just seems your not pulling enough air through the RAD on the trail, you could start out and replace the thermal clutch fan and see if that helps (Again about 5-7 year lifespan), but again if your rad is over it's time, time to replace it. I had similar problems as you. I started out with the water pump/ T'stat then went to the fan clutch, then finally new rad. The fan clutch actually gave me the best improvement, then after the rad change, 2 row modine, I am back to "normal" were it used to be the first 10 years of it's life. I've been running this "new" stuff for over a year and has not once gone over the 210 line, even in 95 degree Florida heat.
EDIT: My XJ is a 95 and things will be slightly different if you have an 80's XJ.

Alex
 
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