My '73 q-jet (800 cfm buick unit) has a couple idling issues. The idle when cold is way too low, and the car wants to stall while warming up. The choke works perfectly though. The idle once warmed is way too high when in park. In gear it's fine but in park it's reving so high that the car wants to keep running after shut down. Is it possible to adjust the idle down and the fast idle up to fix these issues? I'm not sure how these adjustments will effect each other so I figured I'd ask before I start messing with anything. I know the carb needs to be rebuilt but I'm trying to get it to at least run some while I get all the parts together for the carb swap. It's been sitting for too long and I need to be able to at least take it around the block once in a while without worrying about damaging the motor.
There is usually a fast idle adjustment on the passenger side of the carb, a screw that sits on the fast idle cam, and the regular/warmed up idle adjustment on the drivers side. Fast idle adjustment. Warmed up idle.
I have couple of Q jet guides on http://boattail-riviera-by-buick.com/library/documents/documents.php dont rule out vacuum leaks collapsing vacuum lines either -
SilverBuick has the right pics there. Adjust the cold idle up using the screw on the pass side under the choke cam. turn it in to raise the cold idle Once the car warms up the choke cam should rotate all the way down and free, at which point your idle will be set by the screw on the drivers side. turn that one out to lower the hot idle. This assumes a properly functioning choke, and no vacuum issues etc etc. It would be worth checking the settings and adjustment of the choke linkages according to the service manual
Thanks a bunch guys. I read the manuals and looked at diagrams but it was all too confusing to figure out. Now it makes perfect sense to me.