Antifreeze

[monkeyhanger]

Does antifreeze have a shelf life? I have a 5 litre bottle of neat blue antifreeze which must be at least 10 years old. Will it still have all the necessary properties, such as rust inhibitors, to make it ok to use? Thank you.

[Ex Brummie]

If it's not been opened, it should be OK, but for peace of mind, it's only the price of a couple of coffees to buy new.

[blackrose]

10 years might be pushing it a bit. Personally I'd buy new and I'd drain whatever is in the engine and use red long life antifreeze rather than blue.

[Richard10002]

If you change from one colour to another, do you have to flush it thoroughly, or is it enough just to drain the old stuff and fill with the new stuff?

[Boater Sam]

6 hours ago, Richard10002 said:

If you change from one colour to another, do you have to flush it thoroughly, or is it enough just to drain the old stuff and fill with the new stuff?

Colour is not the relavent proviso, its what it is made from. Blue is generally ethylene glycol, red is usualy propylene glycol.

 

They should not be mixed, if in doubt, flush.

A good flush is a sound idea anyway to remove sludge and contaminents.