So got all of the replacements parts installed - new fuel/oil lines, duckbill valves, air filter, spark plug, and cleaned/rebuilt the HDC27 walbro carb.
Reinstalled everything and the saw starts up right away, but seems to run erratically. As in idle speed will be all over the place and quite frequently will stall out. The strange thing is, it seems like the low speed adjustment screw isn't doing a whole lot and RPMs jump all over regardless of where it's at.
The only thing I didn't replace in the carb was that little floating, disk check valve thing that sits under the circle gasket plate. If this piece isn't functioning (deformed, swelled up from carb cleaner, etc), what are the symptoms? Any other ideas?
Also, the cork gasket on the caps aren't sealing. I tried rubber o-rings in the caps and I thought they were sealing well, but the bar oil has a tiny trickle out the cap when under pressure. Should I be looking to try a flat rubber washer the same size as the old cork gasket?