nba1341

So I just cleaned out my overflow tank and it was full of rust that just hunk out there and it was like a mooshy slimy rust similar to mashed potatoes.

I reattached it and now days later there is just a tiny bit of rust now floating in there and i open my radiator cap and its all green and no rust in there.

Is this another purpose of the overflow tank? My radiator was recently flushed so is some rust normal?

andrewmp6

Do you have a alum or copper radiator?If its alum you have to run distilled water or you run in to problems like you see.

Carlos Pineiro

If only your rad was flushed, and not the engine, there would be significant rust, as you mentioned. Flush the rad & engine well and refill with coolant. Good luck.

CP

tx65coupe

I agree with whats already been said, but are you sure its rust and not just dirt? I have seen expansion tanks get dirty inside. I guess it depends what type of cap it has. The screw on kind shouldn't have this problem, but the ones that just sit on top of the expansion tank can have this issue.