I assume the engine cranks but doesn't fire. If not, you need to trace the electrical problem - check the battery, check the ground, check the terminals on the battery for corrosion, check the cable attachment on the other end, check that there is voltage at the starter solenoid from the wire from the ignition switch, check that starting voltage is passed thru the solenoid, check the starter motor.
If it cranks but doesn't fire, that is a classic problem and just requires some detective work. Most obvious things to check are spark and fuel. Both go bad when sitting idle for long periods. Pull a spark plug cable, stick a screwdriver in the cable, hold the metal blade of the screwdriver about 1/8" away from a good ground and crank the engine. If you see a blue spark, that system is likely OK. Next take off the air cleaner and pump the throttle and check that the accelerator pump is squirting gas into the carb. If not, it could be a bad fuel pump, plugged fuel line or tank filter sock, or bad needle and seat in the carb. Another common fuel problem is a bad needle and seat that allows gasoline to pump in mass quantities thru the carb into the engine but that is usually easy to detect from gasoline oozing out of everywhere.
Do these checks and get back to us.
