So after the suggestions from my last post, I have gone ahead and had my mechanic completly flush the system, install the 3row "radiator barn" radiator, duralast waterpump, new fan clutch, new hoses, and a new 195 tstat. Jeep still runs between 215 and 225 (mostly 225) Any thoughts on what could be wrong still? I know it's not the gauge as I have tried 3 differant ones (each time with a new sending unit) The newest is an expensive autometer. Just had an oil change and the level is fine. Hopefully someone on here has some more suggestions to look into. TIA

Also, not to stir up the debate any more, but my mechanic right off the bat asked why I was going with the 195 insted of a 180 tstsat. I said it seemed to be the consensus on here.(he is very familiar with this site) His opinion was it would run cooler. The one thing I wanted was to at least get the vehical to run 210 (normal) before adding upgrades to lower it further. I have already done the radiator with no results.

 

Have u verified temp with a point-n-shoot infrared temp gun? What are ambient temps (triple digits I bet)? Efan on? We've been running a 180 for 19 mos now......this time of year a 180 vs 195 will make little if any difference, 6 mos from now, yes. 225 definitely seems toasty.

 

on a privious post i had the same problem i tried everything you have tried and a few more resister between the wires right before sensor, 180 tstat high performance waterpump new belts pullies fan clutch i mean all. untill one day i blow the head core plug. no other option but remove head and install new plug. in the process of re adjusting the head rockers i notice the lack of oil comming from the rods. i immediately took it to the shop and come to find out the oil pump was 95 per. blocked. they cleaned the sluge as best they could and cleaned the pump. after the mech told me to run seafoam treatment and after that a karosen flush for 10 min. then oil run flush and service sence then no overheat even in desert at 125 deg. she is never over 195 never

 

Sorry to hear you spent all that unnecessary money. Your mechanic is incorrect since the thermostat only controls the minumum temperature not the maximum temp. It would start your cooling cycle a little earlier but would eventually run at normal temp. I run a 180 in mine and it performs basically the same as the 195. In the winter I will change back.

3 things come to mind on your problem.
#1. Did you check the impellor blades on the new pump next to the old one? There are reverse flow water pumps and they will barely cool the motor.
#2 I know you changed your hoses, but idle the Jeep and then raise the idle to about 2000 rpms and observe the lower hose and see if it collapses. With a cheaper brand hose, at higher RPM's (normally driving) the lower hose can collapse and slow down the coolant flow. You may need to transfer the spring from the old lower hose.
#3 the system was bled from all air correct?

 

.........Is your aux fan kicking on?

 

I was thinking this as well, but I was hoping that his mechanic was competent enough to check this since he did all that work to it. But, you never know. Good call man.

 

Fan shrouds in place/intact?

 

If everything else is OK, and the fans are working, it's probably going to be in the head.

 

Might wanna do a block test to see if ya go any hydrocarbons in the coolant. That will tell ya if you have an issue in the head.

 

Ding ding ding!!! Something allll too often overlooked!!! There should be a spring in your lower radiator hose to keep it from collapsing.... is there?? A spring??

 

My auxillary fan wasn't working, resulting in some overheating issues... I ran a ground to the body, and a wire to the back of the alternator. Keeps the fan running the whole time the engine is... but ONLY when the engine is, so it doesn't suck all your juice dry. Other thing you might want to verify... rad/water ratio. Good Luck- Have Fun.

 

Also, if you choose to go my route, realize... number1, run the wire to the alternator all along the body, behind/under the batery, and to the terminal on the back of the alternator. Wire placement is VERY IMPORTANT! If its somewhere it can rub or get melted, you can ground out your electric system. Be careful, do some planning. Also, if you live where it's cold, you'll have to undo this during the winter. Just food for thought. Jerry-rigging things often results in hassles and give/take. Weigh your options. If you wanted to get fancy, you can run a toggle switch to it. Use a heavy duty 1 if you do. Like from a tablesaw. So you don't have to keep replacing them. Or have the switch over heat... ok, no I'm just rambling.

 

If you have replaced everything in the cooling system, and it is still runnng hot, then maybee the problem is elseware.

An engine running to lean or with a clocked up exhaustsystem will also run very hot.
How is your engine performing ?

Insufficiant oilflow will also make the engine run warmer.
Have you done a oil change lately ?


Good luck with it and let us know

 

hmmm, you don't say? I just had this discussion with another member who shall remain nameless trying to tell me there is no reason anymore for the spring. Doesn't know why, just doesn't need it. Can't say it's the OP's problem, but definitely something to check. Goodluck on finding his problem.

 

.....at least I admitted I didn't know why (it didn't have a spring). LOL Lots of folks have forgotten more than I'll ever know.

Before I did the hoses on our XJ, I had read about the spring in the bottom hose so when the 1st parts store bottom hose didn't have a spring, I said no thanks, and kept looking. 4 stores later bought a bottom hose with no spring. The bottom hose (doubt if it was original) we removed from the 12 year old XJ didn't have a spring either. Again, I don't know why (no spring) and won't try to dream up a reason as to why. I do know this, on our XJ, when the motor starts building a little heat and it's all sealed up, that bottom hose is just as hard as the top hose.

As I mentioned previously if the coolant bypass has been removed/blocked, then maybe the bottom hose would shrink a little but even then, the water pump is a centrifugal pump, NOT a positive displacement pump.