KT40
SILVER Star
Yeah carb was rebuilt by @JasonH and it runs like butter.
Had to have been some trash.
So that hole is not part of the inner workings of the carb intake it?
Full window must have been my clue bowl was stuck?
I am not an SD40 expert but older carburetors are pretty simple. The hole is the vent for the fuel bowl and yes, I would agree that gas at the top of site window was your indicator.