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Hi Folks - Are there any gurus out there with real experience with the 912 series Rotax engines? (Not the old two-strokes) For sure, they have issues that the Continentals don't have, and a couple of pluses. For what I hear from those who have them, some of the myths and issues relate to: 1. Liquid cooling. Yes, they are partially liquid cooled in the cylinder barrel area, with the heads being air cooled. The manual for the Tecnam says that if you lose coolant, retard power to 55%, and fly on all day long. At low power like that, the air cooling is sufficient for the entire engine. Remember that 60 years ago, the Mustang, Spitfire, Me-109, Hurricane, P-38, Lancaster bomber, et al. went thru a whole war with liquid cooled engines. 2. Hi RPM - True, the thing cruises around 4800 engine rpm. High by the standards of the 1930s when the Contis were designed, but not high by today's standards. My car runs 3400 rpm at 70 mph, and the one I had before this one wasn't even burning oil when I sold it at 150,000 miles. 3. Light weight and streamlined. Here's why Rotax is being used in so many LSAs - 100 hp from an engine that is far lighter than an O-200, and the frontal area is far less, allowing a more aerodynamically efficient front end for the airplane. 4. Used to be far cheaper to overhaul. Anyone know any real life overhaul costs now? 5. Premature top end failures/overhauls. This seems to be directly tied to the use of a steady diet of 100LL. When operated on car gas, the issue goes away. Remember, that in Europe, Avgas is extremely expensive. My cousin, who is an FBO in Switzerland, tells me that he's seen Avgas as high as $9.00/U.S. gallon (No typo - yes, $9.00). So Rotax designed the engine to run on lead free auto gas, and the certification for 100LL is an after thought, mainly for the U.S. market where auto fuel is hard to deal with at airports, unlike in Europe where it's available. Thanks, and looking for any real life experiences. Jerry E. ============================================================================== To leave this forum go to: http://ercoupers.com/lists.htm Search the archives on http://escribe.com/aviation/coupers-tech/
