Engine Temperatures

[18burningtrails]

Yesterday I noticed the temperature gauge on my 2002 Liberty moving. It stayed about 1 tick above half for my entire 15 hour drive. Sometimes it spiked to 2 ticks above half (last tick before red tick). It never got to red and no alarm ever sounded.

I don't normally pay much attention to the temp, so maybe this is normal.

I looked up the temps in the service manual. Here's what's happening

normal - 255
center of red - 260
high end of red - 269

So I'm probably operating around 258 degrees.

Should I be worried? What tick mark on the gague is considered "bad"? Just red?

I had a coolant fill and flush done a couple days ago. Could that have caused the problem?

Thanks

 

[jnaut]

Should I be worried? What tick mark on the gague is considered "bad"? Just red?

I had a coolant fill and flush done a couple days ago. Could that have caused the problem?

Thanks

The answer is "possibly".

Most KJ drivers here NEVER see the temp gauge go above the 1/2 way mark (I'm in this category) because, as you discovered, it's an "idiot" gauge. Meaning that it's showing you the temperature in 'bands'. Normal OT it's dead center, anything over that is outside normal spec.

I don't know what climate you're in (so hard when people don't put their location, and yet so helpful when people start asking questions which relate to environment) or the exact conditions. Were you towing? Were you going over a mountain pass? Was the Jeep heavily loaded down?

Plus, the engineer in me is looking at a red flag: you say you've never seen it done this way until you had a coolant flush.

Some possibilities:

1. the coolant flush dislodged a bunch of crap, but didn't get it expelled from the system, and now it's restricting coolant 'flow' throughout the system.

2. Whoever flushed you didn't tighten something down and you're leaking or did leak coolant: you're running low.

3. Nothing's leaking, but they just didn't refill it properly.

4. They filled it properly, but the rare yet possible condition has occurred where there's an airbubble inside the main engine cavity, and the pump is just cavitating air thus restricting flow.

Start by making sure the coolant level is proper. Go from there.

 

[18burningtrails]

Thanks for the helpful reply.

I didn't put my location because I drove across half the country yesterday and it acted the same everywhere. Even did the same thing here around town today. Although, it is 100 degrees out here today.

I checked the level of the coolant at a rest area along the way and it was filled to the top. Nothing seemed to leak last night on my driveway.

Not towing anything.

I'm thinking the radiator is partially plugged up. Can a radiator guy unclog it, or would I need a new one? Do you think it hurts to drive with the temp over half (but below red). I plan on getting this fixed, but I have another 15 hour drive tomorrow planned.

 

[tjkj2002]

Thanks for the helpful reply.

I didn't put my location because I drove across half the country yesterday and it acted the same everywhere. Even did the same thing here around town today. Although, it is 100 degrees out here today.

I checked the level of the coolant at a rest area along the way and it was filled to the top. Nothing seemed to leak last night on my driveway.

Not towing anything.

I'm thinking the radiator is partially plugged up. Can a radiator guy unclog it, or would I need a new one? Do you think it hurts to drive with the temp over half (but below red). I plan on getting this fixed, but I have another 15 hour drive tomorrow planned.

Get your cooling system fixed ASAP,all your doing is damaging the heads and burning up the trans.You also will need new trans fluid also as those high temps will kill the fluid fast which in turns kills the transmission.ATF+4 only for the trans and HOAT coolant only for the coolant,best bet is to let a dealership handle this so you know the correct fluids are being used which is worth the higher cost.

 

[jnaut]

I'd follow tjkj's advice on this.

Now that you gave us some background, this definitely isn't normal. Ahtough rare, believe it or not, even here in Seattle we do get the occasional 100+ temperatures. By logic, I would see a fluctuation in my temp gauge on those days if this were normal, and I never have. Temp gauge has always sat squarely at dead center. So if you're consistently seeing higher than normal temps under normal driving conditions, something's wrong.

I would think that if the radiator isn't clogged in some super-severe way, yeah, there may be some technique that a good radiator shop can perform, maybe a back flush or something.

There was a case recently here where someones water pump impellor was broken inside the engine cavity and it wasn't making any telltale noises. Just not moving coolant. Don't rule that out.

 

[Mangate]

I think you would have noticed it before, even if you don't pay much attention to the gauge. I'll put my money on something to do with the coolant change.

 

[Neal]

If it was not a 50/50 mix of coolant/water it will run too hot. Maybe they put in 100% coolant thinking the jugs were 50/50 mix.

 

[LibertyFever]

Yesterday I noticed the temperature gauge on my 2002 Liberty moving. It stayed about 1 tick above half for my entire 15 hour drive. Sometimes it spiked to 2 ticks above half (last tick before red tick). It never got to red and no alarm ever sounded.

I don't normally pay much attention to the temp, so maybe this is normal.

I looked up the temps in the service manual. Here's what's happening

normal - 255
center of red - 260
high end of red - 269

So I'm probably operating around 258 degrees.

Should I be worried? What tick mark on the gauge is considered "bad"? Just red?

I had a coolant fill and flush done a couple days ago. Could that have caused the problem?

Thanks

So an engine temperature of 255 F is okay on a "spark infested" engine?

This past weekend I was driving about with the A/C on and read an engine temperature of 219 F and was getting concerned. I guess I shouldn't until it gets above that 255 F point.

 

[LibertyTC]

My 2004 with 37k miles just had the coolant flushed at dealer. It stays in middle of gauge.
Yesterday while pulling the 3500lb boat back in 90F, the hottest it got was 215 when going slow, and averaged 205 while at highway speed according to my OBDII intel. Air On.
Anyone with higher mileage should consider replacing their thermostat and have the system pressure tested to make sure there are no leaks. Flushing should be done every 5 years.

 

[LibertyFever]

Good point LibertyTC. I should check or replace my thermostat. I have no idea when or if it ever was. With my luck it will fail some hot summer day a long way from home.

 

[tjkj2002]

So an engine temperature of 255 F is okay on a "spark infested" engine?

This past weekend I was driving about with the A/C on and read an engine temperature of 219 F and was getting concerned. I guess I shouldn't until it gets above that 255 F point.

Your electric fan does not turn on till about 219 degrees,heck your t-stat does not fully open till 218 degrees.

 

[LibertyFever]

Your electric fan does not turn on till about 219 degrees,heck your t-stat does not fully open till 218 degrees.

Really, that's good info to know.

thanks...

 

[Dave]

My dash temp gauge is most always at the half way mark. I also have a scangauge and it usually is reading between 198-205 degrees when the dash gauge is in that half way mark position. (OEM t-stat and coolant).

Dave

 

[JeepJeepster]

Ive never had my gauge move. Seen it get as high as 218F but I usually turn the A/C on if Im in traffic so it stays around 195-197F. If Im towing it'll get up to 205F on the hills but thats it.

 

[indieaz]

Ours gets tot he middle line on the dot within 3 minutes of starting, then it sits there without budging no matter how far we drive. We tow a trailer in summer to colorado (about 12 hours of driving) and go through some serious mountain climbs...it never budges. I suspect you have an issue.

 

[SIGguy229]

Ours gets tot he middle line on the dot within 3 minutes of starting, then it sits there without budging no matter how far we drive. We tow a trailer in summer to colorado (about 12 hours of driving) and go through some serious mountain climbs...it never budges. I suspect you have an issue.

My apologies for reviving this Frankenthread....

I just bought a 2004 Liberty with 106k miles and noticed this same thing: temp gauge goes from cold to top/middle of the gauge within about 5-8 minutes. Is this normal?

The maintenance records are spotty, but the engine is in good condition...I'm still planning an oil change, radiator flush, and transmission fluid flush/change so I know where I'm starting from on maintenance. Should I also replace the thermostat?

Right now, temps are from the mid-40s to high-60s. My daily drive is about 25 miles. This is a stock 2WD Sport...no aftermarket parts. Generally used as a daily commuting Jeep. I am planning on adding a ClassIII/IV hitch in the future.

Thoughts?

 

[Luke]

In my experience .. yes. The KJ does not take very long to reach operating temp. Which means fast heat in the winter!

Cheers,

 

[Akedos]

Should I also replace the thermostat?

If you go to the dealership for the flush I would be absolutely shocked if they didn't recommend you get the thermostat changed. I would do it though. Why not spend the money now.