92' Pro50 TLRQ Fuel Leak

[SeaHawk]

I have a fuel leak possibly from a gasket from an assembly (6H4-24452-01-00) located on the port side of the bottom carburetor. I'm not sure what this part is called but it has a diaphragm inside. After opening the unit, the diaphragm was melted/fused on to the cover of part number (6H4-24452-01-00). The plastic disc (6H4-24413-00-00) inside also showed melting around the entire edge.

1. Is this caused by ethanol in the gasoline?
2. What is the name of this assembly and what is its function?
3. There is a lever on the outside of the cover (6H4-24413-00-00), what is the purpose of the lever?

Many Thanks in advance...

[boats.net]

That is the prime starter(auto choke) Ethanol could have caused it. The lever is for manual operation.

[SeaHawk]

How do you use the lever? Do you just lift it in to the out position (away from body) then start the engine? Secondly, when would this lever be used?

Thank you very much for the information. My Yamaha OEM manual did not I.D. this part.

[boats.net]

Should be turned all the way clockwise for normal operation(auto choke).