So I was filling up the new radiator with coolant.

I was using the Orange Prestone stuff, about 40% coolant, 60% water. I also added 1 bottle of the prestone water pump lube/anti rust stuff, and 1 bottle of red-line water wetter, because I had it lying around. I put the additives in first, then started filling with water and coolant.

So, in the process of burping and filling, I removed the AST cap. There is this brown sludgy goop at the top, around the neck and cap, with the consistency of snot. I wiped it off, also saw a little on the radiator cap, and continued filling.

I am wondering if something about the additives, or the order added caused this.

The engine was cold when I added all this stuff.

 

when did you last drive it? it might just be fogging up or water evaporation but that usually happens in the oil filler neck.

 

I don't think order matters..because the end result is all cooling fluid that is designed to be used in radiators.

Raj

 

That brown residue w/ Redline Water Wetter is normal.

 

This was all within a week, fill the coolant, start it, top off, repeat process, etc. I filled with the throttlebody hose removed, and was just finishing the burping cycle.

Glad to know it is normal. I hope it goes away after a while...