Hi Jeff, good decision to go with the YS!!!!
Your OS seems pretty 'F' ed-up to me []. If you want to keep playing with the OS, I would try running it with a stock 7L (non-pump carb) to determine if the performance modifications are working or just ruined the engine. If the engine won't run reliably/consistently with the non-pump carb then it has become a paperweight [:@] - sorry. If the engine runs well on the 7L carb then you need to replace the pump or pump and carb. I've never been a big fan of the 4-nipple pump/2-nipple carb - too much plumbing and I don't think that much fuel gets returned anyway. The Hanno pump/carb works great if you can find one. The OS pump assemblies will last for a very long time if kept clean and no 'adjustments' are performed. There can be wear in the carburetor, though most commonly it is the needle that wears.
Have fun with the Summit!!
-Will B.