For a friend - Rochester Carb Replacement- what is this adjustment?

[370Dancer]

Not sure what the screw deal is on the pull down linkage.
Rochester on a Volvo engine old carb didn't have it

 

[techmitch]

Adjustable pull downs are a nice feature/upgrade. They cover wide range of applications where the area denotes different needs. Think; average temps, altitude and moisture or lack there of.
Wish I could be down there with @scoflaw to help you through your latest endeavors.

 

[Nater Potater]

Based on engine and usage, you should have a note in the destructions telling how to set it, and to what value. Typically, with the choke closed, the primaries are opened all the way, which causes the choke butterfly to be forced open a prescribed amount. If the carb was purchased for your specific application, it "should" already be set. Either way, it's just there to make sure you can manually force a sticky choke to open by shoving the throttle to the stops.

 

[370Dancer]

thanks guys. I'll pass it along.