Possibly stupid question about engine coolant...

GravyMonster · 25 Sep 2011 at 21:34

Hey all,

I noticed this afternoon while checking my oil that the coolant header tank was just a few mm above the minimum. I went to top it up with the bottle of generic Halfords stuff in the garage, but noticed what was already in the car was an orange/red colour, but the stuff in the bottle is blue - is it ok to mix them?

I have googled but I'm getting conflicting info.

Also, while we're here does anyone know what the correct coolant would be for a 99 1.8 A3, as opposed to this generic stuff?

Clarkson · 25 Sep 2011 at 21:56

Mixed blue and red stuff in mine when a leaking tube was fixed. No issues from it and it was a couple of months ago at least.

MeEsH BaKkA · 25 Sep 2011 at 21:59

Some coolants can react badly if mixed, I think it's vauxhalls stuff if you mix the 2 types is turns sludgey.

Either ring a dealer or pour and hope

Liverpool-Lad · 25 Sep 2011 at 22:18

Its probably G12. The generic stuff can mix sometimes to form a gel. Id use a little water or the proper stuff.

Firestar_3x · 25 Sep 2011 at 22:42

I wouldn't mix the two colours personally.

BigglesPiP · 25 Sep 2011 at 22:53

They don't turn it to jelly, but the two can form a precipitate, it's better to just use water.

Firestar_3x · 25 Sep 2011 at 22:55

My turned to foam in the header tank, still no harm done and a valuable lesson learnt!

Bhogal · 26 Sep 2011 at 02:56

I have never had a problem with mixing, but yea, it does say don't do it. You could either just top it up with water or flush it out...or of course mix them! Don't forget if you top it up with just water, you will need to put coolant in soon as winter is fast apporaching....brrrr!

Uriel · 26 Sep 2011 at 06:54

An auto-electrical garage put the wrong stuff in my old Fabia. Formed a weird gel/foam precipitate. Don't do it.

Defcon5 · 26 Sep 2011 at 12:20

Was it hot or cold? If it was cold that level is fine.

Its G12+ you want (assuming it already has that in)

Dogbreath · 26 Sep 2011 at 14:40

Might want to find where your coolant is going as well, the level shouldn't drop under normal conditions. Perished seals on the header tank cap are common and cause a slow loss through evaporation, but you might have an actual leak.

DRZ · 26 Sep 2011 at 14:51

The two types aren't always differing in colour. I had some Toyota Longlife coolant in my MR2 which was a techicolour orange but when I bought some that was chemically identical it was a greeny blue colour.

Unless you know for sure, I wouldn't mix it though.