Hello all. Just got the new gasket and heat shield on my 67 GS400 Quadrajet. From my readings, the proper way to adjust these carbs is to screw in one of the carb adjustment screws all the way in and then do three turns out. Do this to each of the adjustment screws and it should be a good starting point in regards to the fuel mixture. Interesting enough, I screw both all the way in and the car continues to idle just fine and does not even hesitate to turn off. I turn them out three times and no difference in engine idle. Now with the previous gasket which did not have a heat shield or appear be the correct gasket, I would adjust the screws and the engine would react to such adjustment. Any ideas or suggestions?
Sounds like a vacuum leak. You can spray carb cleaner around the base while running and see if the rpm's pick up. If it doesn't, then the problem is elsewhere.
The throttle plates are open too far, letting the engine run on the primary circuit, ignoring the idle circuit. That is what is going on, lots of possible reasons why...
In regard to plugging the heat cross over under carb, are you referring to actually capping the area with something like jbweld or are you referring to using a third gasket between heat plate and carb, where the gasket is similar to heat plate, but different then gasket with smily face?
I would plug it at the head. Who needs carburetor heat in Florida? The cooler the intake runs, the better your performance will be. You may not be able to use the choke, it might not come off if you do. I haven't used a choke in a long time.
