Please help me with this fuel issue

Hi i have just bought a Yiying Tommy 125 for going to work on. I bought it for peanuts as it been standing out side for a while and will now not start. I have checked the spark and thats fine in fact ive squirted some dope down the inlet manifold and it starts for a second so i know it will start. The issue is that there is no fuel getting to the carb. It has some sort of fuel pump inline just after the tank which isnt electric and isnt mechanical ??? so can only assume that it works from suction from the carb. There is no fuel coming through the pump and when conected to the carb nothing is getting to the carb at all. Can anyone give me guidance as to what to do next. Andy..............

 

It works on the vacum from the intake, its needs pulses of vacum and not just a constant vacum like the diaphram type taps. Get the battery good and charged and give it time, it should pump through.

 

Stupid question maybe, but theres fuel in it?
And why was it not used for a while?

 

There is fuel in the tank as thats the first thing i checked as i am not a novice i just dont work on chinese scooters, as for the reason its been standing the guy i bought it off tells me that he bought a car so parked it in his grans yard and left it for nearly two years, then i bought it, but thanks for the vac info i will try it as soon as i clean the carb out as whilst its its in bits i may as well

 

the fuel pump will have three lines .

tank to pump - pump to carb - pump to engine casing (on some models ) or pump to carb vacuum side.

the pump works as said above its a pulse of pos and neg pressure, usually on some bikes like my sym jet the vacuum pipe is connected to thr crank case and uses the crank pressure pulsing to drive the pump, on other versions its the carbs vacuum niple that provides a vaccum suck to the pump to open it (but the carb can and sometimes does not produce a pulse vacuum wave as one would think)

if thats old fuel in the tank and its two years old its going to be in a sorry state, you maybe better pumping that old fuel from the tank and filling it with some new fresh fuel, then giving the bike a good few turn overs to draw that new fuel into the fuel line system.

 

on my vacuum fed carb it has a prime postion if your bike does this could get petrol to the carb with out turning it over