carburetor gaskets

For 4 years I used the BMW nylon floats (about 400 hours) without any problems, even if it was necessary to remove the float guides in the carburetor bowl.

https://www.rotax-owner.com/en/912-914-technical-questions/8823-fuel-level-in-the-carburetor-bowl

Currently, I have reinstalled the carburetor floats as originally, if I sell my Evektor, it is preferable.

When installing the float bowl seals, I also use small dots of grease to hold them in place and ensure the bowl is positioned correctly.
For the users of this forum, I would like to say that I do not recommend modifications to the float system, but that I have tried it, as have the pilots I know who have had nylon floats for almost ten years now without having observed any problems.
I would like to thank everyone on this forum who provides constructive answers to my questions.

Jacques

Hi Jacques

The tandem floats as you have shown have not been used in the aircraft Bing carbs since the 1980s.  They are just fine as long as you have no sinking.  The independent floats were developed to help engines in unusual angles for better float control.  

The black gasket now supplied is not rubber but a synthetic to resist the chemicals of the auto fuels used today.  The cork is fine however when you remove it or let it dry out they are prone to shrinkage that leads to leaking.  They also are not suitable with any pressure in the float chamber (as in the turbo engines) since they will weep fuel on higher boost pressures.  

Cheers

Aren't the rubber type gaskets Viton?

Hi Roger

I am not sure if the gasket is a Viton, Viton is a trademark name.  My understanding is it is in the same family of gaskets.  This is the web description of Viton.

Viton® gasket is a type of high-performance seal made from Viton®, a registered trademark for a fluoroelastomer known for its excellent resistance to high temperatures, oils, fuels, acids, and harsh chemicals. This durable synthetic rubber is used in demanding applications across the automotive, aerospace, chemical, and fluid power industries where reliability and long-term performance are crucial.

Cheers