There was a discussion a few days ago about the early production Renesis Engine having an issue with oil foaming. Talked with a friend about that, as I didn't know the solution.

 

I believe the oil foaming was fixed with a new dipstick. Yes, Lower the oil level until it stops foaming. The problem occurs when the oil contacts the front counterweight. In addition to foaiming, there is an additional  parasitic power loss of up to 20 hp when the oil level is too high

 

One of the other things that came up was the issue of the oil injection pump. With low rpm the engine ECU controls the amount injected. Since the Renesis doesn't have a periphal port, it can not eject a carbon build up. Not an issue with the ECU controlled oil injection pump, but he didn't recommend using older injection pumps for this reason.  The carbon loading is more likely to occur under light loading, so may not be an issue for aviation engines. Still long taxi times may mean were are better off with a good quality two stroke oil and premixing.

 

Also he made it clear that his company does not promote Rotary Engine for aviation.   I just need to get to Japan and provide enough Sake to learn anything more. :)  Funny story, but our host in Japan had made an error in translating "Corporate Director of Engineering" to "Corporate Drinker of Engineering".  I.e. the Engineer who can drink anyone under the table.  Oh my. So I need to return and bring our Corporate Drinker along. :)

 

Tom