Rotax 912 ULS

[pilotyoung]

My Rotax has brass nipples with rubber caps on them on each intake maniford right in front of where the fitting for the crossover tube screws into the top of the intake manifold. On my friends Rotax there is a bolt where the nipples are on my engine. The bolt is a 10 m. Does anyone know where I can buy those nipples and the rubber caps that are on them? Thanks.

 

[GatorsR1]

No

 

[azonslow]

My Rotax has brass nipples with rubber caps on them on each intake maniford right in front of where the fitting for the crossover tube screws into the top of the intake manifold. On my friends Rotax there is a bolt where the nipples are on my engine. The bolt is a 10 m. Does anyone know where I can buy those nipples and the rubber caps that are on them? Thanks.

Check your DMs.

 

[Piper J3]

My quess is someone did a carb balance and the brass fittings were included with the dual-gage setup. Instead of removing the brass fittings, they capped them. Not ideal…. I’d reinstall the original bolt / washer.​

 

[azonslow]

I agree with Piper J3. If so, the Rotax Illustrated Parts Catalog lists the parts as: 641071 for the M6x6 screw and 230415 for the sealing ring (washer). I seem to recall that you need the weakest Loctite made, don't remember the part number but it's weaker than blue.

 

[seagull]

When I had the stock intake manifold I had brass barbed nipples, 1/8” hole, screwed into the manifolds for carb balancing. I initially used vinyl caps, I learned quickly, on the first flight they melted, one came completely off. The clue was the leak sound when I landed. The small amount of air leak didn’t noticeably change performance. My solution was to use 2” long silicone tubing that can handle the heat with a plug in the end far enough away that the heat wasn’t a problem. To use that setup I had to pinch off the crossover rubber hose to isolate the sides, that isn’t always perfect seal. I later made fittings that fit onto the crossover tube and onto the manifold. That removes all doubt about the test. On the current crossover I use the same setup just larger.