Hey all,
I need to replace the thermostat in my '96 ZJ. I just read my Haynes manual and it says to drain the cooling system. Is this absolutely necessary? I'm not really in the position to do that where I live. We're not even supposed to be working on our vehicles out front...bylaws of the place. I park on a slight uphill grade...you think I'd be able to remove the housing and the stat w/o too much of mess? Idea's and suggestions much appreciated. Thanks.

 

I just did mine this past weekend. i was parked SLIGHTLY downhill and i lost probably 3-4 cups of coolant. if you parked uphill, it would probably be less based on the location of the t.stat. I live in a condo and am not supposed to work on my cars as well. I just put a small car wash bucket under the nose, roughly under the crank pulley. just pry the housing off SLIGHTLY and when a little coolant leaks press it back on to stop the flow and look under the Jeep to see where exactly to place the bucket. Hope that helps its really not that bad. Lower bolt is blocked by the belt, but i was able to just push the belt out of the way without loosening it or anything.

Of course now my XJ's temp climbs to 210 then drops FAST to 160, climbs slowly again and repeats this all the time. It just ran cool before. Just my luck. Probably a bad thermostat. Duralast junk, lol.

 

Cool, thanks. Now next question....I was looking at Advanced and Rockauto and found the stats rated at 160-195 degrees. Which is the best way to go? Since they aren't as expensive as I thought they were, would it wise to get the 195 degree one? Opinions?

 

Yeah 195 is the factory temp, i'd go with that. Everyone i have heard says these things like to run a little hot (195-210). Do yourself a favor and dont go cheap like i did. i gotta do it again this weekend now.

 

Before, mine was running cool. About 165 or so. And my mileage i crap, so i was hoping getting it to proper temp would help a bit, but now it fluctuates so much that i cant see how it would.

ALSO, you may already know, but be sure to remove ALL of the old gasket material or you will end up with a (more) leaky Jeep. I just used a razor blade and was careful not to make any nasty gouges in the metal with the edge of the blade.

 

cool bro...thanks for the helpful tips. That sux you gotta do it again. Mine usually runs just a tick below 210. The thing I don't like is that it gets up to normal operating temp within 5 mins of being started.

 

The sooner the engine reaches operating temp the better, it's better for the engine and emissions.

 

NP man. Yeah 4.0's get up to temp really quick. well mine doesn't, but they usually do. And Fall River huh?? Nice. Im up a bit in NH. South of Concord though.

 

That makes me feel better. I thought I had more issues with the cooling system. I ended up picking up a Stant 195 degree t-stat today...got a good deal on it too...score.

Yeah, I used to live southern VT for half my life. Spent lots of time in Keene hanging out with friends and lived there too for a spell. I've been up to Manchester and Concord a couple times way back in the day. Really nice up in your neck of the woods. If my schooling opportunity comes through for me, I'll be a lot closer to there...right in Bedford Mass. Keepin' my fingers crossed.

Thanks again for the info.

 

cool...thanks for the info. Learn something new every day. I actually thought my coolant might be shot because it warmed up so fast. I feel a bit better now.

 

Just a word to the wise.. change your coolent annually. needs to be replenished . the stuff does wear out and won't protect the inside of your engine as it should when it is left in the engine for to long...
Getting the engine up to temp fast is what a theromsate is supposed to do.l Mine ran at 165 or so when I got it because someone had removed the thermosat all together. Put in a 195 and MPG went from 15.7 to 16.4. I have the 5.2, not known for great MPG. I also installed one of the Mark VIII fans, 2 speed, from a Contenial about 95 I think.. Use an adjustable thermo control for the fan to come on at 200. the fan runs very little and is real quite.Compared to the orginal mechnical fan and clutch. Been thinking of changing my thermosat to one that will clock to the open position if it should ever fail. as apposed to the one I have now which would close and block off the circulation and overheat the engine if it ever fails. Just me thinking outloud..

 

Thanks for the helpful info 94zjdriver...sound advice that makes perfect sense. I was planning on having my coolant changed in the next month or so. The only reason I haven't changed it out yet is my lack of mileage. I've barely put 12,000 miles on it 2 years. It is on the list of things to have done though so...hopefully next month!
Thanks again for all helpful tips guys.