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Sinking carburetor floats

backcountry

Well Known Member
I haven’t kept up with the forum lately.. Has Rotax come up with a non-sinking carburetor float yet.
It’s a sad experience when your passenger starts complaining of smelling gasoline fumes.
It’s also expensive to keep replacing these floats. Probably you like me have use engines with carburetor floats and never experienced anything like this.
 
Marvel-Schebler offered their original epoxy floats for Rotax a few years ago where they copied Bing float geometry. This resulted in a float that was too heavy with incorrect buoyancy. The original floats had a flat top surface. M-S redesigned the geometry and incorporated a beveled top surface which lightened the floats and corrected buoyancy. I suspect all the original floats found their way to a landfill. The new design is identified by the beveled top edge. I installed M-S floats a year ago and I think it may be a long-term solution to the problem. The epoxy material is supposed to be impervious to fuel and fuel additives of which 93E10 Mogas has many…
 
The new version of the Marvel Shebler Rotax floats solved my float problems. Part number MS80-430 $165.00 for two floats.
 
Thanks for the information
I just ordered the MB floats.

I stalled the MS floats today and the engine runs great. Hope this one keeps floating.
Thanks
 
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Imagine a flotation device that had a reputation for sinking. I don’t think you can even get them at Walmart.
 
Imagine a flotation device that had a reputation for sinking. I don’t think you can even get them at Walmart.

Right…. The guys with BMW motorcycles equipped with BING carbs need to remember to shut off fuel tank valve at the end of a day’s ride. More than one has been surprised the next day to find garage floor awash in gasoline. At least the RV-12 doesn’t not have fuel tank mounted above level of carbs….
 
I hate to jinx myself, but I had my carbs overhauled at 500 hours and kept the floats as spares. Now at about 1200 TT the second set is fine. You guys must have displeased the Thunder Gods!😝
 
I hate to jinx myself, but I had my carbs overhauled at 500 hours and kept the floats as spares. Now at about 1200 TT the second set is fine. You guys must have displeased the Thunder Gods!��

Correct again. My Bing floats (3rd set) where operating fine and within weight spec when I changed over to Marvel-Schebler epoxy floats.

I had enough fun with sinking floats and fuel overflowing onto hot exhaust stacks to last me a lifetime....
 
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