Weird Overheating.....Sometimes

[sleepyjim]

Ok so I can offroad at a snails pace with full a/c on in 110 degree heat all day long here in AZ, no issues. Last week went to the Grand Canyon camping for a few days, now the libby was loaded but not extreme weight or so I figure, anyway going up hill 75 ish passing I would see my temp gauge rise toward OH NO! I would let off gas, cut a/c and it would creep back to center.....I did notice my tach was 4500 & + when this happened........

Never had this issue before....Ever.

So just to much on the 3.7? To much weight?

What ya think?

I will get out and try it empty (no camping stuff) and see if it happens again.


Jim

 

[LibertyTC]

I use a scan gauge ODD2 digital temp reader. Oh no does not tell exactly what temp it actually got to.
How many miles on the KJ & has the water pump ever been replaced?
Do you have just the electrical fan or also the HD clutch based one?
The electrical fan should be on any time the AC is on & anytime it hits 227F.
Every 5 years the system should be flushed with HOAT coolant only & the dealer re-circulating machine is the best way to accomplish this.
Throw a new Mopar thermostat in there, & replace any old hoses with Mopar ones may be a good idea too.

 

[Myke]

I use a scan gauge ODD2 digital temp reader. Oh no does not tell exactly what temp it actually got to.
How many miles on the KJ & has the water pump ever been replaced?
Do you have just the electrical fan or also the HD clutch based one?
The electrical fan should be on any time the AC is on & anytime it hits 227F.
Every 5 years the system should be flushed with HOAT coolant only & the dealer re-circulating machine is the best way to accomplish this.
Throw a new Mopar thermostat in there, & replace any old hoses with Mopar ones may be a good idea too.

I believe my electric fan comes on with ac or 219°

Funny thing is I just ran into this issue today too. Would run very hot with ac on going up some big highway hills. I had my scanner connected and it got to 230 once but stayed around 226. I turned the ac off and it went to 219. Which is still hotter than usually. I'm typically in the 200-219 range on days like today (90°)

I parked it and when I came back out to check it there is a grinding noise coming from the compressor. I will dig into it tomorrow and verify it's the compressor and not the water pump with a stethoscope. The compressor has 152k miles on it but the entire cooling system has been changed in the last 15k miles. Everything Mopar except water pump which is a gates.

This all happened after accelerating onto the highway and coming close to redline. Was fine for the hour drive into PA to "not buy fireworks".

I will update you on what I find tomorrow. I do not have the HD cooling fan, and I am not regeared. So I may have 2 separate issues here (compressor going bad and inadequate cooling).

 

[sleepyjim]

I use a scan gauge ODD2 digital temp reader. Oh no does not tell exactly what temp it actually got to.
How many miles on the KJ & has the water pump ever been replaced?
Do you have just the electrical fan or also the HD clutch based one?
The electrical fan should be on any time the AC is on & anytime it hits 227F.
Every 5 years the system should be flushed with HOAT coolant only & the dealer re-circulating machine is the best way to accomplish this.
Throw a new Mopar thermostat in there, & replace any old hoses with Mopar ones may be a good idea too.

Ok lets answer these.....99k miles, water pump changed yesterday, hoses and rad changed about 5k miles ago, with thermostat. I have just electrical fan, new with rad. It is working. (I am gatehring parts to do the HD fan), only HOAT.


Now what exactly is an ODD2 temp reader and how much are they?


Jim

 

[sleepyjim]

By the way LibertyTC, where did the girl avatar that kept staring at me go?


LOL

Jim

 

[LibertyTC]

Ha Ha.. :Whoa: she went to Waterfront Park for the Canada Day Celebration & a swam in the ocean yesterday..then onto the dance floor last night, after the fireworks !
Thank goodness the place was air conditioned, things were getting pretty hot in there! :licklips: (beerthought)
Talking Hot... My jeep will get to 219F+ in stop & go traffic easily (normal) w/o the HD cooling clutch fan- Need hood vents- and my Autel TP-100 scan gauge comes in handy to also clear P codes.
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You must be registered for see images attach

The scan gauge II is still available and clik on monitor to see all the extra gauges: https://www.scangauge.com/products/scangauge-ii/
:cheers:

 

[Myke]

Ok lets answer these.....99k miles, water pump changed yesterday, hoses and rad changed about 5k miles ago, with thermostat. I have just electrical fan, new with rad. It is working. (I am gatehring parts to do the HD fan), only HOAT.


Now what exactly is an ODD2 temp reader and how much are they?


Jim

I have a Bluetooth obd2 module and connect to my phone running an app called Dash Command. Some users prefer the Torque Pro app but I wasn't a fan.

I attached a pic of the one I use.


Also its definitely my compressor. Have you had any issues with your ac when it was running hot? I'm thinking one of the sides had too high pressure. Going to a funeral but will pop a manifold on it later.

You must be registered for see images attach

 

[sleepyjim]

Change the above mentioned parts install to 3 years ago, not 5.

No load, just empty jeep, overheats on highway hills if a/c on.......Other than doing the HD cooling, which I am doing but never had before and never had this issue so I do not see how that is the answer......

Thinking winch on bumper causing it? It does block some of the grill. Maybe after the HD cooling it will fix this.

Jim

 

[sleepyjim]

I have a Bluetooth obd2 module and connect to my phone running an app called Dash Command. Some users prefer the Torque Pro app but I wasn't a fan.

I attached a pic of the one I use.


Also its definitely my compressor. Have you had any issues with your ac when it was running hot? I'm thinking one of the sides had too high pressure. Going to a funeral but will pop a manifold on it later.

You must be registered for see images attach

Like the bluetooth mod and ordered one. Thanks!

No a/c issues at all, of course when the temp rises at a certain point the a/c cuts off to save the motor......

Thinking mine is the winch. Weird that it only happens at a certain RPM....

Jim

 

[Myke]

Like the bluetooth mod and ordered one. Thanks!

No a/c issues at all, of course when the temp rises at a certain point the a/c cuts off to save the motor......

Thinking mine is the winch. Weird that it only happens at a certain RPM....

Jim

I too have a winch and a light bar above the Fairlead.

 

[sleepyjim]

I too have a winch and a light bar above the Fairlead.

Well I am at a loss...... I can not see it being a hose, thermostat I would think either works or dont and if not working I should overheat at all RPMS on hills. Ditto for rad.

Maybe a flush would fix it....


Jim

 

[tjkj2002]

If the A/C being on causes it I'd be suspecting a air flow issue causing to much heat soak in the radiator.

More weight,bigger than stock tires,hills,AC on,grill mostly blocked,and not geared correctly is finally showing it's weakness in the ability to properly cool.


Remember higher rpm's at slow speeds(low load,say in 4 low on the trial) adds cooling,higher rpm's at high speed cause more heat with high engine load.

 

[sleepyjim]

"Remember higher rpm's at slow speeds(low load,say in 4 low on the trial) adds cooling,higher rpm's at high speed cause more heat with high engine load."

Never thought about this, I see it.....Gonna do HD cooling as next step.

Thanks

Jim

 

[tjkj2002]

Never thought about this, I see it.....Gonna do HD cooling as next step.

Thanks

Jim

HD cooling is a band aid fix at best.

Last road trip with my late KJ was to MOAB,had to go up to the Eisenhower tunnel in Colorado,7 miles at 5000 rpm's,lugging 6400lbs+ to 11,000 feet,and no HD cooling never went above 224 degrees with the AC on.

 

[sleepyjim]

Only thing different is the winch on front and it aint getting any lower so HD cooling it will have to be.....Nothing else changed/added.

Jim

 

[sleepyjim]

If the A/C being on causes it I'd be suspecting a air flow issue causing to much heat soak in the radiator.

More weight,NOPE
bigger than stock tires,NOPE
hills,YEP same as before
AC on,YEP as normal
Grill mostly blocked,NOT MOSTLY BUT ADDED WINCH
and not geared correctly SAME AS WAS
is finally showing it's weakness in the ability to properly cool.

Only winch added


Jim

 

[tjkj2002]

Only thing different is the winch on front and it aint getting any lower so HD cooling it will have to be.....Nothing else changed/added.

Jim

Hankook 245/70/16's, Steel Diff Cover, Engine, ****** & Trans Skids, Roof rack

And a winch that covers 50% of the grill.

HD cooling only adds low speed cooling for towing.It's only a mechanical fan which when "locked" reduces engine power by about 5%.

 

[sleepyjim]

And a winch that covers 50% of the grill.

HD cooling only adds low speed cooling for towing.It's only a mechanical fan which when "locked" reduces engine power by about 5%.

So winch has to go? Thats terrible.....LOL

Not arguing, just po'd....

And I do believe the winch/air flow was ok till recently.....

 

[tjkj2002]

So winch has to go? Thats terrible.....LOL

Not arguing, just po'd....

May need a different mounting.

Why I chose the ARB bumper,moves the winch lower and the bumper protects the winch.

 

[JeepJeepster]

Have you checked to see if the fan is kicking onto high speed?

I really wish I would have added the mechanical fan sooner. After adding it the A/C gets cooler quicker and the engine has never went over 204F. I like keeping things at a constant temp.