Mark, it appears you will have to go through the process of removing the fuel tank and carburetor from the engine, then removing the fuel tank from the carburetor. In between the two is the fuel pump diaphragm. Inspect it, looking especially for flap valves that are stiff or will not lie flat. If the diaphragm has deteriorated, it has to be replaced with a new one, which will cost you about $10. If the diaphragm looks good you'll need to clean out the fuel pickup strainer, and the fuel passages in the carburetor, with clean fuel, or with carburetor cleaner. Do not let carburetor cleaner spend any time in contact with the diaphragm, and it might be wise not to use fuel with ethanol in it in future.
