Do you like the taste of gasoline? I do.

Just pull the fuel line off the carbs, and suck on it until you see the slightest bit of gas in your filter. You should be able to suck through the fuel pump.

To check if you've got gas at the pickup line in the tank, you have to remove the fuel line at the before the fuel pump, connect a hose to that line so you can blow back into the tank. Have an assistant listen for bubbles in the tank with the filler cap removed. This will also let you be sure the line isn't blocked. You won't be able to blow back through the pump though... if you can, the pump diaphram is probably shot.

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-Matt I ♥ my ♂