I have a 2200 Jabiru on my CH701. For a while I couldn't find an engine oil leak, it was and still is, nuisance value more than anything, using probably less than a teaspoonful of oil per hour, barely noticeable on the dipstick but spread nicely on the lower cowl. I eventually discovered that, inside the rocker boxes there is a small hole drilled through the back at the top, which exits between the fins above the cylinder. This I discovered was factory designed to prevent carbon build-up on the valve stems (I think) Anyway, a very small amount of oil or oil vapour blows out of these holes. The only suggestion from the factory is to lower the oil pressure, which I don't want to do. I am sure that somewhere on this site I read about that problem but I cannot find the post. Their solution had been to fill the little holes with high temperature RTV and to drill small holes in the rocker covers. I am hoping that whoever that was will read this and give me details of the size and positioning of the hole in the rocker cover.