I have a 10 hp b&s on a genearator and it runs good on full choke and runs ruff when I trun the choke off. Also is there a way to bypass the on/off switch? It is kind of in pieces.

The air fuel mixture may be off. Check spark plug to make sure its good and not carbon-ed up for a cooler spark which needs more fuel to run.

If that's good its more than likely the air fuel ratio is off. Its not getting too much air when choke is off and runs rough. If there are air fuel balance needle valves there cut down a tad on the air amount. And take off choke.
It will take some playing with the air fuel mixture balances. You can try adding more fuel and go that way. If the choke is on full add more fuel until the motor starts to load up and smoke. Now back off choke and see what half choke does. If it runs good there then add a tad more fuel until the motor changes then go to no choke and see if it runs good.

You may only have an air adjustment to work with and use that to balance Air fuel Mixture.

This is assuming you have good spark. That's the first thing to make sure off. Check/clean plug or new plug

The on off switch could be replaced with any proper Gage switch that completes the connection. You need to connect the wires to shut off motor other than over choking it to shut down. This will eventually dirty the plug internal parts. Best to use wires at switch even if you jimmy rig another switch.


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