Hello, I am currently rebuilding a Rochester 2GV carb for my '71 Skylark. I am wondering how to set the off idle air screw which is on the back. Any thoughts? Thank you
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I already have the Bible, thanks. The problem is, that it tells me that there is no way to set that screw " in the field". Apparently it is a factory setting.. But there should be a way.. can't imagine that the whole thing is garbage now just because I pulled that screw...
Thank you Larry. Now I understand the purpose and function of the system better, but how do I set that screw properly? Turning it after initial tuneup would mess up my idle/mixture and idle rpm setting?
You mean you just removed it without noting the adjustment? From what I read, it regulates the idle speed by regulating idle air bypass. There is a similar circuit in Q-jet carburetors but it isn't adjustable. Idle air bypass enables the throttle blades to remain nearly closed at idle. Opening the throttle blades too much at idle causes fuel to be drawn from the main nozzles. I would set the throttle blades just a bit open and play with that adjustment to get the best idle.
Yeah, usually I make notes and Fotos of everything I take apart. Somehow I got carried away on that particular one.. Funny though that it seems impossible to find that information.. Thanks anyway Larry
Yes it's an idle air bypass. I dont know a stock setting, though it seems like that would be in the service manual. Personally I would screw it all the way in which should eliminate the bypass air. Adjust your idle mix and rpm. If I had nozzle drip at idle then, i would open it up some and readjust idle settings. Repeat until you have no nozzle drip. Idle air bypass is more about throttle position at idle than idle mixture.