• NAXJA is having its 18th annual March Membership Drive!!!
    Everyone who joins or renews during March will be entered into a drawing!
    More Information - Join/Renew
  • Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.

OVERHEATING - tips and things to check

Avanteone

NAXJA Forum User
Location
Auburn, WA
To some of you, this all may be general knowledge and you will just say, "DUH".... but after so many rigs overheated last year, I thought I'd post up some simple tips or things to check. The XJ's cooling system is only marginal in perfect operating condition on a stock rig. Add lifts, big heavy wheels, tires, bumpers, winches, etc. and they are even more prone to overheating. The long hard pulls up the forest service roads and even some of the hills on the trails make the Naches area hell in an XJ.

XJ's ('87+) have both a mechanical fan with thermal clutch, and an electric fan. The electric fan should come on using the fan switch any time the rig gets up to like 210*. It also should come on any time the a/c or defrost are switched on. Make sure that it comes on when running the a/c and that should confirm most of the system is functioning properly.

The mechanical fan clutch should be tight, not freewheel. When the engine is cold, grab the fan and spin it, it should spin but have some resistance, not just freewheel. If it does, replace the fan clutch. Also, the fan shroud is absolutely ESSENTIAL on XJ's. If you don't have a fan shroud, get one. They're like $20 brand new at the dealer.

Thermostat. Many people will try and patch an overheating problem and replace the factory 195* thermostat with a 170* or 180* unit. This can actually make things worse as it doesn't keep the coolant IN the radiator long enough to cool it back down. The best bet is sticking with the 195* thermostat.

Water Wetter. This is a product made by Redline (same guys that make the synthetic oils), that works AWESOME. Somehow it changes the chemical properties and eliminates the little tiny air bubbles that happen inside the radiator and cooling system. It's under $10 for a bottle, available at Schucks and most auto parts stores, and can easily drop coolant temperatures 10-15*.

John
 
Installing a CSF 3 row radiator today, and just put in a new 195 thermostat and a new overflow bottle. No to mention finished my lebaron hood vents. :thumbup:

Good info though John! Brings up some points I think some have over looked.

~Scott

P.S. I have a brand new aluminum hi-flow water outlet with gasket for anyone who wants it, $10. Test fitted it on my rig and my water pump outlet is too close for comfort.
 
That little farker. I say we beat him senseless and steal all of his booze.

I have a couple of spares I made from grade 5 bolts. They'll get someone off of the trail. If Axel needs one, it'll only cost him a hundred dollars.
 
Alex owes me about $200 bucks then. You bringing spare leaf spring center pins this year, Axel?


I just got my spares in the mail and I put brand new ones in my leaf springs a couple months ago.
 
Also Shucks has premix coolant 2 for $10, good time to stock up.
 
That was at the PNW Jeep run at Evans. Well, I didn't beat him up, Big John roughed his drunken ass up a bit though. That was after I drug him over to his tent and convinced him to share some of his rum. I remember it was "Pirate Booty" rum, which smacks of fudge-packing on the high seas. I assume he'll bring the same brand this year, him being into that sort of thing. Either way, he still owes me for the epic leaf-spring center pin fab/install job I kicked him off of and did for him to get us back to camp before midnight at NW Fest last year. I'm assuming that debt will never be fully repaid and I'll be drinking his rum for the foreseeable future.
 
Back
Top