First time seeing this, but this is what I drained from my car. It's not separating and doesn't appear to be oily. Should I be worried?

 

 

If at some time you mixed green with orange coolant, the resulting mix may be brown or black, and it can form a sludge. Drain and thoroughly flush it all out, and don't forget the coolant overflow tank.

 

^Yep. Do a few drain/fill cycles, probably start with distilled water (90 cents a gallon at the grocery store) until you get it clear then fill up with plain green Prestone 50/50. There's zero reason to use any fancy coolant in an FD, it's designed for green Prestone, use it. Change it once a year and your cooling system will always be happy.

Dale

 

FYI Water wetter type products also cause the coolant or water color to change to an ugly brown color. Could be a factor as well.
Anyway, here's my past experience flushing a dirty cooling system: https://www.rx7club.com/3rd-generati...lushes-977577/
Have fun

 

On top of which other more modern coolants are known to allow/cause corrosion if there is ANY air left in the system. Green ethylene-glycol AF works fine in a cooling system like ours if the air is not totally evacuated.

 

Flushed!

 

don't forget the bolt on the center Iron.

 

I remembered. Thanks!

 

*Disagrees in Evans NPG+*

 

yes yes yes 👍