Hi - I'm working on a 48 Fleetline with a Rochester B carb. The idle speed adjustment doesn't seem to stay - as soon as the accelerator pump linkage is moved the cam looking piece (1/4 round piece with the ridged on the edge) tends to rotate down, changing the idle speed. I'm hoping someone can explain the idle speed cam connection and operation. I'm wondering if there is a piece or connection missing (spring, etc) - I don't see this particular type of adjustment mechanism in the Chevy shop manual or any other Rochester B picture/video I've seen. Not sure if the screw connecting the cam to the carb is supposed to tighten to keep the adjustment or what but looks like the prior owner tried to spot weld the cam to the screw (note the small blob of metal on the cam) so it can't be tightened... Any help appreciated!
