Brown ast coolant?

[interloper393]

Any idears on why my coolant in the ast tank is brown but the main fillup section is still red? was change a few weeks bck and i`ll be doing it again soon with the blue coolant b4 u have a go at me lol..

ta

[interloper393]

any idears? looks more like mucky water as theres no gunk anywhere in there or on the dipstick...

[buckman67]

Generally there are only a couple of things that turn your coolant brown and that is rust or radseal.     If your ast is still clear then it pretty well eliminates both of those as any longer term problem would have muddied the water everywhere before now.  If you have no overheating issues i.e. poor circulation then its a mystery, best to do as planned,lose the lot, refill and monitor.

[ashc]

silly q - is it really brown, or just looks it because the interior of the ast is dark, and the filler neck is shiny? red liquid in a dark container can look quite brown ?

[Timmy]

isn\'t red/pink coolant the wrong type for rx7s it can react with stuff.
I thought it was blue/green only.

[ashc]

the pink is ok so long as its changed regularly, i think it is meant to turn a bit acidic after a year or two. (propylene glycol). I tend to do a summer & winter change anyway, so no worries.

[tezz12345]

pink is ok if its the right one that does not  corrode

[interloper393]

kewl so a coolant change it is, cars never run over 85, starts hot or cold and never loses water, just a bit odd, looks more like dirty water, thought maybe its just as its the ast then any crap in the coolant would go to this as its higher ? hense the reason its only showing in the ast tank.