1991 3hp dies at idle

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1991 3hp dies at idle. Like it runs out of gas like idle circuit has dirt in it. Cleaned carb twice including removing low and high speed jets, blowing everything out. There is a tube in one of the jet cavities, could that be the culprit?
Fuel pump diaphragm looks fine and bowl is always full after it dies so it's getting fuel. Idle mix screw is backed out as far as it can be. Turning in just causes it to die sooner.

[boats.net]

Try giving it a little choke to keep it running, if can then still have plugged passage or jets in carb.

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Yeah choke helps of course......I'm thinking of soaking carb overnight. Must be something stuck in idle passage resricting it. Mixture screw affects it so there is some idle flow but obviously not enough.

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Cleaned carb again and it ran great...then the next time it clogged again. The fuel and fuel tank are clean but I noticed that according to my factory Yamaha service manual that there is supposed to be a screen in the inlet of the fuel shut off valve. Mine is missing. Could that be the issue? Rather than buying a new fuel shut off valve I was thinking of getting a small fuel filter maybe from a weed wacker?

[boats.net]

Be sure all the fuel lines are clear from debri. Also remove one of the fuel lines and inspect, sometimes with older models the new ethenol fuel will eat line from the inside out.