My FS130 will run as long as the carburetor high speed screw is turned all the way in. As a result, on the subsequent cold start, the purge bulb will push in but takes a long time (> 1 minute) to become whole or full again. If I back out the high speed screw, the purge bulb will operate normally but the engine will not run in high speed due to excessive fuel. The valves have been adjusted to 0.004" cold, plug gap is set at 0.020", plug type is NGK CMR6H (the correct plug), flywheel key is not sheered, the flywheel to ignition module gap is 0.008", the crankcase holds pressure at 7 psi and holds vacuum at 7 psi, the impulse signal at the carburetor is present with both pressure and vacuum being read as the engine is cranked, the carburetor inlet fuel line fitting holds 10 psi and holds a vacuum after the purge bulb is depressed (and the high speed screw is turned out), the return fuel line fitting at the carb. holds pressure when the purge bulb is depressed, and the muffler is free and clear. Any suggestions? Has anyone run into this issue and if so, what is the fix?