8 replies to this topic

[fenghuang]

I need to top up my rad.

I have an unopened container of ready mixed coolant.
By unopened I mean the plastic ring around the cap is unbroken and the cap has not been removed. BUT ... I suspect there is nothing like a foil seal under the cap as there is less coolant in the container than I would expect to see. Perhaps 10% less, and I guess the container has sat unopened in a dark cupboard for a couple of years.

I'm sure I've read stuff about not using old coolant once it's been opened, but any thoughts on this scenario?

[dklawson]

I have never heard such a warning.  

 

Coolant in a radiator is generally recommended to be changed every 2 or 3 years.  Coolant in a sealed jug should not have degraded perceptibly in that period.  I find it very unlikely that the fluid has "evaporated" as you suggest.  It simply many not have been filled as full as you hoped or thought.

 

Also see the link below.

http://www.doityours...ar-antifreeze#b

[sledgehammer]

I think (but am no expert) that coolant starts to degrade when it is in contact with the water jacket / rad , in the engine - iron , ally , copper , etc

 

also going thru heat cycles will break it down in time

 

sat on a shelf in a plastic container , I should imagine it would take ages to break down

[fenghuang]

Good news. Thanks.

[peter-b]

Just a little side note, you can get little test strips for checking coolant. Castrol sell them. You just dip one and compare colours to that on container.

[gazza82]

If you're stuck top up with distilled water. I live in a hard water area so filling from the tap furs up a rad in a few years.

[Ethel]

It certainly used to have a shelf life, hence why it disappears off the store shelves until the onset of winter each year. There should be a date marking somewhere on the bottle.

[Blatherskite]

Coolant mixes are not just antifreeze, they also have additives to reduce corrosion, especially of any alloy components. Thats why you should use it all year round.

[dklawson]

Please see the link below from the Prestone web site.  In the U.S. Prestone is one of (if not the) most common brands of antifreeze.

http://prestone.com/...asked_questions

 

Their reply to the question about shelf life is:  sealed container, not diluted... many years.

That does not mean all antifreezes would be "good" for many years and there are different formulations.  However, since antifreeze is typically good 'in an engine' for 2 to 3 years, it certainly will be good in a sealed jug for more years than that.