N_Jay

Probably that same way I know.

wshymas

So I had the wife pick up a coolant tester. I checked the coolant mix when I got home last night and it is a weak mix. Only good to about 0 F. So I did not do a good job of mixing the coolant this summer.
Shame on me.
I ordered some more coolant and I will have to drain and refill to try to get to a good mix.

jcman

Good find! Hard way to find out but at least no damage, sure beats replacing a t-stat

SloopJohnB@mac.com

And add raw coolant in the amount of ½ the system capacity. You can add water for the rest of it except for the last ½ gallon or so…use 50/50 mix. That way you'll have at least 50/50 but probably more, 55/45.

If you use 50/50 mix with a drained system, you'll get less than 50/50 when done because part of the system will be less than 50/50, can't drain the whole system without draining the engine and that engine plug can be difficult to get to unless you've done it before.

N_Jay

You can also use Zerex G05 which is a lot cheaper than VW/Audi G13.

Are you sure you did not use premixed and then add 50% water?

Harleyguy

Antifreeze in too weak a solution will gel or begin to slush up like a Slurpee at the 7-11 if the ambient air temp drops below the protection point of your mix. Lived in northwest Wyoming for over 30 years where -40 can easily happen. Without knowing how much remains in the system after draining it is hard to tell what your % should be on the new stuff. In extreme temperatures approaching or exceeding a mixture of more than 55% can also cause the antifreeze to gel once it goes through a few heating and cooling cycles. If you know your system's capacity you could do some math and add straight undiluted antifreeze after only partially draining the system. The container should have a mixing table printed on it. Find out what your current ratio is based on your hydrometer check and adjust accordingly. Also DO NOT mix the two types of antifreeze together. Mixing propylene glycol with ethylene glycol can also cause the mix to curdle or gel.

kelisko

Why would people want to mix coolant with water anyways? Is pure coolant bad for the system or what? Also won't the sediments in the water clog the system with time? Unless distilled water is used, of course.

N_Jay

Pure (concentrated) coolant has relatively poor heat transfer properties.

Always use distilled or at least deionized water.

SloopJohnB@mac.com

And yes, pure audi coolant isn't what should be used, not pure water unless an anti corrosive or additive is used, and generally pure water (additive acceptable) just for track use because dropped mixed coolant on the track is bad news/slippery.

Nice thing about Evans is it doesn't require a pressurized system.

kelisko

I see ... Audi coolant is not available here so I usually buy the best quality available sold at a TOTAL gas station which says "made for hot countries". I recently lost coolant in my C6 and topped it off with it and it seems to be doing its job well. They said in the instructions not to mix it with water, but it can be mixed with other types of coolants.