One more Rochester 2jet (or 2gc) carburetor question. Regarding the fast idle cam. There appears to be four steps. Can you help me identify what each step does or moreover which are supposed to be utilized so I set my carburetor choke up correctly. Thank you.
With the choke plate fully closed, the idle screw should rest on the step you have number #1. That gives you fast idle on start up. As the choke begins to open the cam drops until you have normal warm idle. You do have to open the throttle slightly to get it to drop.
Here in SoCal I turn the choke to rest on #3 with a full pump cold on start up. After running a minute or 2 I’ll back out of the garage. The slightly higher idle helps. By the time I’m out my housing tract I’m good to go. In the first mile or 2 I may get a stumble needing additional squirt and I’m ok with that.
Check around pages 12 and 13 at the link below and see if this helps you get things back together the right way. It may not look exactly like your carb but it should still give you a pretty good idea how it all works together. http://www.carburetor-parts.com/assets/2 Jet.pdf