Overflow? carb not firing

[sparkybr74mr]

On my 81 CBX, when I have fuel running to the carbs my number 3 carb does not fire, I believe the fuel is overflowing and flooding the cylinder out and yes I have come out with a wet plug. When I shut off the fuel flow after a few seconds the number 3 carb starts to fire, again making me think that fuel is flooding the cylinder. I believed it was the float needle, but after swapping it out with one off another carb and a second time with another float needle all together and re-setting the float the same problem still exists. I had that same problem with my 79, but with the number 1 cylinder, after swapping out the float needle on the 79 she now fires every time without flaw, just dont know whats going on with the 81

[steve murdoch icoa #5322]

Sparky, i am not quite understanding your terminology.
When you say #3 is firing and not firing do you mean running and not running? Or do you mean you are pulling the plug and lead and not getting a spark?
I would think if the float, float needle or float height were giving you trouble you would have gas puking out of the bowl.

[daves79x]

Your overflow has to be running on #3 if it's flooding for that reason. Otherwise it is plugged and that's not good. You'll fill the cylinder and hydro-lock it. You don't have the primary and secondary mains switched on #3?

Dave

[sparkybr74mr]

I am 99.875 percent sure I found the culprit. I should have taken the fuel shut off valve when I had the chance. It was sucking in fuel to the #3 carb from a torn diaphragm.

[daves79x]

There you go!

Dave

[Larry Zimmer]

Thanks much for this feedback, Sparky. Might very well help someone else. This is one that I had not ever heard/seen. Because I have by-passed the valve on my '82, years ago, just never would have thought of it.

Thanks, again.