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This may be a very easy fix since the engine starts and runs if you prime it manually. First flip the machine on its snout so that the handles are facing straight up in the air. On the right side (behind the off key and inside the metal box) you will see the carburetor. There should be a small (1/4") black hose that comes from the primer to the carburetor. A lot of times this hose deteriorates right at the carb and rots off. Cut it back and place it back on the inlet nipple on the carb. Now your machine should start normally.