I use an automotive fuel pump. If you have a Racor filter, it will most likely have two inputs and two outputs. You want to pump the questionable fuel thru the second input--that way you are not running the fuel thru the filter.
The automotive fuel pump, needs a small inline paper type of filter or screen mesh type of filter. You want the pump, the battery powering it (can be the boat's battery) and the container you are putting the fuel into away from the boat. I use an. ignition protected switch.
If you don't have a razor, then take the hose off the motor and attach the suction hose to the automotive inline pump to this.
Legally discard the fuel, or burn it in small engines, mixed with fresh fuel.