Title says it all
Looked around and couldn't really find the info.

Had this car like 6 months bought it with 127k miles now has 135k

The entire time I had it prior to this 2 hour drive the temp always ran a notch under
the half (185 degrees) when on the 2 hour drive out about half way I noticed the temp started approaching the middle temp line (200 degrees)

Got there then drove it around that town and seemed fine back down to 185°

Next day headed back for another 2 hour drive and the temp got a little hotter than 200°

A week later decided to do a coolant flush because of the temp. Did like two flushes with prestone orange. 1st with distaled water and 1 bottle of prestone coolant flush then the next with just distelled water and a little tap.
While doing the flushes I let it run until the temp heated up and blasted the heat full blast

After the two flushes then filled with 50/50 dexcool orange and it was still running hot. Driving it around to test the temp went all the way up to about 240 before I shut it off.

After this I have continued to bleed air out of the system with the bleeder valve over the last couple days. I beleive I got all the air out of the system now

and I have added coolant to the radiator cap and overflow tank every morning. I squeezed the upper and lower houses cold when doing this to try and force it in the whole system. Buddy even told me to elevate the front end higher than the back to try and get all the air out and I did that.


Problem is, it is now running 200° - 210° and will occasionally run like 195 under 60mph

I know these Temps are what vehicles run at

Just Makes me uncomfortable just seeing as how it used to always run at 185° before this long drive..


New radiator cap

No more air is coming out of the bleed valve

Both upper and lower radiator hoses are hot to the touch after operating temp

Overflow Reservoir tank is to the fill line even when cold

Sorry for the book just wondering if anyone else has experienced this same thing with the 3800 series in these years and bodystyle
I'm not sure what the next step is and not trying to put the least amount of money in it as possible lol

 

Did you install a new thermostat? 210 F is normal, 240 F is not. You have no exhaust bubbles coming up to the radiator? Are or have you checked the water pump for any reason? Your lower hose shouldn't be hot to the touch. Are you flushing the heater core as well?

My guess is your radiator is going south. You could try an alkaline flush, but It's lots of work, and you need to use protective gear.

 

What was the outside temperature when you took this drive ?, Are the electric fans coming on as they should ?. The temperatures are not out of line and you could still have a trapped air pocket in the system.

 

Yeah my buddy said he thinks it could be a water pump
​​but l What are the symptoms of that? I don't really know what to look at there for a failing one.

I didn't flush the heating core I don't thin? I just did the procedure I outlined. Bottle of prestone coolant flush, then distilled water with some tap and turn on the engine until it got up to like 200 F, shut off and drain the water. Did that a couple times and bleed the air out with the bleeder valve. Air pissed out of that valve and waited until there was a constant little stream of coolant

and did not replace the thermostat. Thermostat just cuz the hoses are hot indicating the coolant circulating through the system. The thermostat looks very simple to replace, but don't want to unless that's probably it.

Yeah i don't know. It's running at 185 again BUT only under like 45 mph. Soon as I get on the freeway it goes to 200-210 F

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Like 98 degrees or something. Both fans are coming in yes

Hmm yeah and would just bleeding it out of the bleeder valve take care of that?

I have a radiator shop that will do a courtesy cooling system test and I think they could pressure test it not sure if that would help or be able to further tell if there's anything wrong or what the problem is

 

You can flush the heater out by blasting water down the hoses, but you will need to keep the radiator cap off when doing so, as the water needs to go back into the cooling system, unless you pull them both off.

I think you need to find out what your thermostats rating is at. Should be around 190-210 degrees. In years gone by they came with a small 1/8th inch hole to help get all the air out. You can drill one in the flat spot in the middle of the unit to do so, but it shouldn't really be necessary, and the metal is hard. I'd be less time-consuming to chuck it out for a new unit. That way you know it's operational at it's designed temperature, all of the time.

A water pump has a seal/bearing assembly that can go bad, so they come with a weep hole on the bottom, that leaks coolant if the seal and bearing assembly fails. The vanes that pump the coolant almost never fail. They are made of stainless steel on most vehicles, or at least they were, and hopefully they still are.