In my neck of the woods, humidy tends to be QUITE high throughout the year.

I run Cool Power on all of my glow engines. Some of these have been sitting for two or three years after their last runs.

When I went to check them out early this year, I found absolutely NO rust in the engines.

Glow fuel tends to inherently absorb water. Castor content has little to do with that.

If you leave fuel with water content in the engine, you are bound to get rust over time.

But that will happen with ANY fuel, no matter what you use.

This is not a characteristic of Cool Power or other synthetic oil fuels, as is being implied, but rather habits on the part of the pilot/owner.