How can i fix a priming problem?

alright so on my motor scooter engine i try and prime it by pressing the bulb thing and gas will go up the line but when i quit pressing bulb the gas will go back down the line into the tank. anybody know whats up here?

Could be a bad primer bulb- its leaking air and not holding a charge of fuel. Check the gas cap if it vents.

yea its fixed. the there was a air leak dangerous. the fuel lines werent sealed onto the carb right so air was getting in