wrote:

Sounds like he had a defective heater. They shouldn't be gettings
things above 212F which would be needed to boil off water or acid.


Matt


Water vapor will slowly come off at much lower temperatures. All it
needs is to condense on something cooler than the oil. I don't recall
if he had crankcase heating only, or if he had cylinder heat too. I
recall the jug sitting above his desk at work, very thoroughly
corroded on the bottom in one winter.

The original post said the water and acid boiled off, not evaporated.

A cylinder that is being used once in a while won't corrode as the oil
film from the last flight will protect it for at least a couple of
weeks. If he let his airplane sit the entire winter, then he had no
need to use an engine heater!


Matt