Butterfly Valve on Carburetor

[secretariatslew]

So the butterfly valve on my carburetor won't close all the way. It gets pretty close, but I'd imagine that I could idle a bit smoother if it would close all the way. Have any advice? This carburetor is off of a 2000 Mercury Mariner 40hp 2 Cycle 2 Cylinder motor.

 

[Chris1956]

Re: Butterfly Valve on Carburetor

How much does it stay open? Why does it not close?