After squeezing the fuel ball to a solid state, the motor is started and it will run for about 3 minutes. At this point the motor stumbles and then stalls. Fuel is being drawn directly from a can through the ball to the motor. Fuel ball goes soft. All connections and hoses inspect ok. Oil pump seems to be functioning. Continuous squeezing of the ball will allow the motor to run. Fuel filter is clean. While squeezing the ball I noticed a little fuel drip forming at the "pimer solenoid fitting". Perhaps the o-ring behind the fitting is allowing air in to interupt fuel flow. Any assistance will be greatly appreciated.