I noticed the other day that my fuel guage said empty even though it has plenty of gas. It was running fine so I just figued the guage was messed up. Now after running some of that gas off it is stalling unless the fuel petcock is set to reserve. Are there 2 pickups, 1 for On and one for Reserve? Can anybody diagnose this?

Thanks

 

Think about it this way, there are two straws going up into the gas, one is short (for reserve) and the other is higher. As the gas gets below the higher one, it runs out, yet, there is still a little under a gallon left in the tank, which is the reserve portion.