Thank you, Mark, your explanation clears up a lot of misunderstandings I had about the gurgling question. Just one more question: What pushes the oil out of the engine when you gurgle, since there is no blow-by to do the job?
I replaced the oil, oil filter, fuel and fuel filter. I checked the pistons and sleeves as well as I could through the spark plug hole. Which wasn't really very good. There is a thin layer of deposits in the cylinders, but I looks like is coming off. The spark plugs look brand new. After 27 hours I would have expected them to look worse. The test flight was perfect, with everything, including my confidence in the engine, in the green.
Blue skies
Arthur
