Is my coolant still good?

[mojobaby]

Hi everyone, I have half a container of radiator coolant\antifreeze. It's premixed-the kind that you can buy in supermarkets. The bottle is marked for temperatures down to -25 degrees and it used to be green, but the colour has completely disappeared and its now completely clear, like water.

My question is, has this stuff got a shelf life? I've had it for about 4 years in a sealed container. Could some of the chemical additives be deteriorated, causing the loss of colour?

 

[ggcton]

Hi everyone, I have half a container of radiator coolant\antifreeze. It's premixed-the kind that you can buy in supermarkets. The bottle is marked for temperatures down to -25 degrees and it used to be green, but the colour has completely disappeared and its now completely clear, like water.

My question is, has this stuff got a shelf life? I've had it for about 4 years in a sealed container. Could some of the chemical additives be deteriorated, causing the loss of colour?

I would say do not take the risk coolant is so cheap and often colour change is the sign to change it.
I have found the cheapest place to buy quality coolant is my local Renault Agent now there is a surprise.

 

[mojobaby]

Thanks ggcton, I know its not expensive, thats not the issue, and I'll probably end up buying another bottle.

I can't pour the old stuff down the drain and I can't even empty the container on the ground, so I'll probably have to take it to a special depot for disposal. I'd prefer using it in my car and hence the question of whether or not it has a shelf life.

I take your point about the colour change.

 

[mojobaby]

Went out today to buy a new bottle of coolant/anti-freeze. I usually buy the green product that is marked for temperatures to -25degrees
What I found surprising was that the green bottle was marked "for French cars"
Next to it was a red bottle, also for temperatures to -25, but it was marked "for German cars"

There was also a bottle marked "Universal" I couldn't see the colour because it was in a white plastic container. They claim that it could be mixed with any antifreeze.

I've since found out that two important components of antifreeze are Borate and Silicate.
Borate helps maintain the PH of the antifreeze to help against corrosion of iron ans steel engine components, whereas Silicate helps protect aluminium against corrosion.

Asian antifreeze which is red, has neither. They use phosphates which are banned in Europe