My 1980 puch maxi lux won't start. i just bought it and on my second ride it quit on me. i was able to get it started again but i had to have the throttle pegged to keep it running. after that trip it won't start at all. i disconnected the fuel line because i thought i might had been out of gas. but when i opened the line about a pint of brown gas came out. i replaced the gas and it still won't start. i have compression and spark. i opened up the fuel line again and now nothing will flow out. please help me.. it beautiful outside.