[RyanAK]

Thanks, man! This was a two month struggle on my daily (only!) driver. Let me sit on the interstate. Did a bunch of things including replacing the mechanical fuel pump. Seemed to be ok for a while, then symptoms came back. Did more things, including the carb rebuild and rigging up a pressure gauge to monitor while I drive. At wits end I decided to swap in ANOTHER new fuel pump. Problem seems to be solved. Good to know I’m likely good with the PSI!!

Lesson learned. Don’t assume your new parts actually work!! Diagnose, diagnose, diagnose!!!

I know about the solenoid. Mine doesn’t have that either. The “idle compensator” on this 4MV is some sort of widget and a cover that goes on the back of the casting on the carb. According to the exploded view in the rebuild instructions. There seems to be some sort of air passage that may or may not be blocked off by the air horn gasket...