Back on 08-18-02 I made the original post. I did a coolant change/flush and after a few months of solid driving the stick comes up perfectly clean.... NO GOOP!!! I think it was the watter wetter.?

 

No it is Oil&Combustion products - ALL rotaries (even BRAND NEW) push a small amount of combustion products out past the seals into the coolant at start up, this crap floats, so it works it's way out through the AST to the overflow tank and accumulates. as the seals fail it does get worse.

 

ahh, i see...so basically just doing regular flush/chang of antifreeze keeps it cleen in there.

 

Every 3rd gen will have a little on that on the dip stick. Mine has had it for 50k and now problems.