Originally Posted by Harvey rv12
I had the same issue when I bought my 12. The fitting was making contact with the muffler body. I thought the friction would rub through the fitting and dump all my motor oil while inflight. After asking around here on VAF, I left with the same feeling, "that's the way it is". I saw that Rotax uses the same banjo fitting on the stock engine. I installed it on my aircraft and have been happy since!.
I think you are right that there may be some dimensional errors/stackup with the muffler system.
For those of you that know us at Aircraft Specialty/TSFlightlines, "That's the way it is" is NOT our mantra. We love working with other builders/owners to try to build a better mousetrap. On my dad's RV-12 the 90 degree fitting does not make contact with the muffler body, but it is close.
We worked with Jim to test fit the Stock Rotax Banjo fitting, and it is definitely a huge clearance improvement over the 90 degree fitting on the bottom of the engine. However, as Tom mentioned, we are also working on our own proprietary banjo fitting that will function directly as one of the Teflon hose ends. This will eliminate the -8 AN nut on the end of the hose which still has a pretty tight clearance on the bottom of the engine casting.
For those of you who are looking at this option, the new Banjo fitting will not be in production and tested for approximately a year, and will provide no substantial benefit over utilizing the current banjo fitting and AN setup. It will be a slightly more compact solution with more clearance on the engine case, but muffler clearance will remain the same.
Thanks again to Jim for helping us to verify this installation. We have said it many times, but really really appreciate the help of the RV community to help us in our product ideas, development and testing.
If anyone has any questions on the RV-12 oil kit we offer, or the different options available, please feel free to reach out to us.