Running Warm at Idle

[orange57]

Hey guys,

I have a 00 Limited, it's a great truck. However, today, while sitting at idle in a parking lot, AC on, the truck temp started to rise to the 210 mark in the dash. Once moving again the temp dropped pretty quick. This is pretty recent, never had an issue before.

First thought was fan clutch. Did a quick check, it does not spin freely. Spins about a quarter turn before stopping. Could that be an idicator of the clutch being bad?

Thermostat is about 9 months old, as is the coolant. I did the Intake Gaskets about 9 months ago and that is when the Tstat was also done. Not to say it isn't the culprit.

Just wanted to get the groups take before I start replacing parts.

Thanks,

matt

 

[SunlitComet]

what rating of t-stat did you use?

 

[orange57]

what rating of t-stat did you use?

It was the oem rating. I believe 195.

 

[God]

How long had you been driving? My Tstat usually takes a few minutes to open, and opens at around 210 and after it opens stays around 170ish I believe

 

[SunlitComet]

getting up to 210 is not abnormal but the way you describe it it sounds like it is delayed a bit and suddenly pops open and and closes at a rate just as fast as it opened. it sounds like a t-stat that is not throttling properly. if you are sure the fan clutch is operating properly the redo the t-stat. a good test for the clutch is to let the engine get cold. start it and listen for the fan to howl as you jack up the rpm's say 2-3k after a short amount of time the clutch will loosen it's grip and not howl so much till it sees a lot of heat from the rad again. if you think you hear howling at higher rpm when the temp gets up your clutch should be fine.

---------- Post added at 06:44 AM ---------- Previous post was at 06:43 AM ----------

How long had you been driving? My Tstat usually takes a few minutes to open, and opens at around 210 and after it opens stays around 170ish I believe

that is to low to stay open at. I suggest yo may need a new one as well.

---------- Post added at 06:48 AM ---------- Previous post was at 06:44 AM ----------

I would suggest you guys use a delco or stant t-stat. I have not had any defective stant products before and they do great thermostats and gas caps as well.

 

[orange57]

How long had you been driving? My Tstat usually takes a few minutes to open, and opens at around 210 and after it opens stays around 170ish I believe

I had driven around 15 miles, then st idling for about 15 minutes. The temp dropped back down once I started moving again.

 

[SunlitComet]

are you sure the system is completely bled out of air?

 

[orange57]

are you sure the system is completely bled out of air?

Pretty sure. It has been 5-8k miles since I did the intake gaskets. Had to add a little bit of coolant right after, but nothing since. And going down the road the temp is fine. Even in the 110+ days here. It was only during idle. And after sitting for around 15 minutes with the AC on.

I will have to listen tomorrow morning to see if I really hear the fan howl. If not, may need to start with the fan clutch. When it cools down I will pop the radiator cap to try and see how the coolant in the radiator looks too. The overflow tank seems fine.

 

[God]

What's the correct normal operating temp?

I think it's kinda dumb that our gauges have 210 in the middle
Whereas many other cars have their normal operating temp in the middle...

 

[SunlitComet]

not at all. in fact running at 210 is not all that bad. when you drive in the city under hot weather with the a/c on it is totally expected. expect more with towing.

the temp will go up and down but mine rests at about 193 at idle to 213 before my fans turn on i think. i could make it tighter but no need.

---------- Post added at 04:33 AM ---------- Previous post was at 04:31 AM ----------

Pretty sure. It has been 5-8k miles since I did the intake gaskets. Had to add a little bit of coolant right after, but nothing since. And going down the road the temp is fine. Even in the 110+ days here. It was only during idle. And after sitting for around 15 minutes with the AC on.

I will have to listen tomorrow morning to see if I really hear the fan howl. If not, may need to start with the fan clutch. When it cools down I will pop the radiator cap to try and see how the coolant in the radiator looks too. The overflow tank seems fine.

Giving that info i don't think you have much to worry about. it does seem like the stat maybe a bit sticky however giving your environment i see no harm being done to the engine. if you get into the 220's while driving with out a load then you may need to be concerned.