Freeze protection issue

[mjoekingz28]

While it is on my mind I am preparing for winter. AFAICR, we have never gotten below the teens in Fahrenheit. On this 2006 Cobalt LS 2.2 Automatic With c. 135,000 miles I did a few drains a month or two ago. I pulled the lower rad hose, let it drain, refill with water, reinstall hose, run to temp, pull hose drain repeat.

Now I do not remember exactly but on the last drain I put a quart or two of straight dex in her. I have been running it like this since. I am in fear the straight dex is still in the surge tank and never mixed with all that water in the system. I just pulled a sample and got about -30F of freeze protection. How so when only the last fill was with antifreeze and all others were plain water?


Man I dont enjoy pulling those spring hise clamps, but it is small tomatoes compared to a frozen block.




Is there another place to pull a sample?

 

[4wheeldog]

Originally Posted By: mjoekingz28
While it is on my mind I am preparing for winter. AFAICR, we have never gotten below the teens in Fahrenheit. On this 2006 Cobalt LS 2.2 Automatic With c. 135,000 miles I did a few drains a month or two ago. I pulled the lower rad hose, let it drain, refill with water, reinstall hose, run to temp, pull hose drain repeat.

Now I do not remember exactly but on the last drain I put a quart or two of straight dex in her. I have been running it like this since. I am in fear the straight dex is still in the surge tank and never mixed with all that water in the system. I just pulled a sample and got about -30F of freeze protection. How so when only the last fill was with antifreeze and all others were plain water?


Man I dont enjoy pulling those spring hise clamps, but it is small tomatoes compared to a frozen block.




Is there another place to pull a sample?


50%/50% mix is generally rated at -35 to -37F. How much does your system hold? You may have 40% or so in there, assuming that you tested the radiator, and not just the overflow tank.

There are reasons other than freeze protection to run coolant at 50%.

 

[Jetronic]

everytime the engine heats and cools back down there will be some dexcool from the surgetank mixing with the fluid in the radiator. after a couple of weeks of continous use the mixture in the surge tank and in the engine will be the same strenght.

 

[mjoekingz28]

Manual states 6.8 quarts.

I think I will hover around the 25-33% dilution from now on. I suspect all of those DexCool problems were from using a long life coolant at half and half, it is just too thick and toxic, especially down South. Like, why run M1EP for 3k intervals? I think they tried to make every vehicle leave the factory identical-whether in NW territories or Ciudad Juarez, Mexico.



That is the thing. I highly suspect it is not mixing. I think the tank's coolant just sits there, like brake fluid. Maybe paranoia is setting in. Saying goodbye to summer is not always easy

 

[Oro_O]

Jetronic is right, it will mix gradually with use, and very quickly in summer.

If your test strip shows -30F protection, that also implies the mix has happened and you are at or a little below 50/50.

From the (extensive) reading I've tried to do on the subject, the "deathcool" problems were bad chemistry, 2-eha not agreeing with components in water pumps and then headgaskets. I do not believe your engine was one of the affected AFAIK. Keep in mind the coolant is also your corrosion protection so running it low is not wise, especially in warm climates. 40/60 or 50/50 is good and no harm to your vehicle.

25% coolant is only getting you freeze protection to 10F. The freeze curve is very steep. Also you are compromising corrosion protection at that level. I would not run it that low unless I couldn't afford coolant and lived in Cuba.

 

[HTSS_TR]

Most car companies recommend 50-50 mixed coolant/water, some allow as low as 40-45% coolant, but none lower than that.

50-50 is optimal for lower freezing point, higher boiling point, anti corrosion, lubricate water pump ... for area not seeing below minus 30-35F in winter.

 

[Yah-Tah-Hey]

Coolant expands when the system is at operating temp and the only place for it to go is into the surge tank. Coolant system cools down and some of coolant is displaced back into engine. That is why the radiator cap is a two-way valve. Jetronic go it right. It mixes.

 

[kschachn]

Originally Posted By: mjoekingz28
Manual states 6.8 quarts.

I think I will hover around the 25-33% dilution from now on. I suspect all of those DexCool problems were from using a long life coolant at half and half, it is just too thick and toxic, especially down South. Like, why run M1EP for 3k intervals? I think they tried to make every vehicle leave the factory identical-whether in NW territories or Ciudad Juarez, Mexico.

That is the thing. I highly suspect it is not mixing. I think the tank's coolant just sits there, like brake fluid. Maybe paranoia is setting in. Saying goodbye to summer is not always easy


Just like in your other thread on coolant, what you think, believe or imagine is not correct nor does believing it make it true.

All coolant manufacturers specify a lower concentration limit (as well as a higher one), and this is not to sell more coolant nor is it a detriment to your cooling system as you imagine. There are sound technical reasons for the limits. You bring up Mexico - you do realize that proper coolant concentrations elevate the boiling point, not just suppress the freezing point, right? You do realize that don't you?

Running a concentration outside of the manufacturer's published limits IS a way for you to cause a problem. Which you will then no doubt blame on the coolant.