Van's RV-12 Build: Rotax clean-up, fuel tank troubles - Subscribe to EAA166 Hartford, Connecticut As the RV-12 project moves closer to the ground-running phase, it's time to take a closer look at the Rotax 912 ULS engine installation and do some preventive clean up. Work continues on the lower engine cowling, the canopy frame, plus the team gets creative in fixing an unexpected snag with the fuel tank plumbing. Project lead Rick Montero talks it through in this build update video.