GoN4Broke
Member
Hey all. Doing my very first annual. Took the Rotax Repairmans inspection class 8 months ago. All went very well with the structural stuff but when I turned my attention to the engine I came up with an issue I hope someone will tell me is no big deal. Some background; my RV-12 first flew last Aug (2016) and has accumulated 49.9 hours total time. For the last 20 hours I have used 100LL exclusively. When I was inspecting the engine I noticed a slight grease/oil stain emanating from the #1 exhaust port. Nothing much and I figured it might just be the exhaust manifold bolt might have been a little under tightened. When I pulled the spark plug out of the #1 cylinder it was fairly dark and there was a slight bit of residue on the threads and it was dark as well but not as dark as the #1 plug and it didn't appear shiny.
I checked the #2 & #4 plug and they were both more or less grey with no residue to speak of. There is no other visible external leak and I have not experienced any vibration, misfire, high oil temps or anything else that would indicate loosing oil. The oil was first changed at 20 hours and then again at 46 hours with no noticeable loss in fluid between changes.
I checked the Rotax Line Maintenance manual section 12-20-00 and the findings indicate the following - possible valve stem seal, misfiring, too much oil in the combustion chamber or worn cylinder or piston rings. I have less than 50 hours on this engine and am hoping the situation is not that dire. Any thoughts ??
I checked the Rotax Line Maintenance manual section 12-20-00 and the findings indicate the following - possible valve stem seal, misfiring, too much oil in the combustion chamber or worn cylinder or piston rings. I have less than 50 hours on this engine and am hoping the situation is not that dire. Any thoughts ??
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