quadrjet adjusting
dumbplumber
08-28-2004, 06:11 PM
I have a brand new 350 and have put on a rochester quadrajunk. Now I need to know how to adjust the stupid thing. By the way it is non electronic. The thing runs ok at higher speeds but it idles terrible. What are all of the adjustments or where can I find out how to adjust it?
GMMerlin
08-29-2004, 09:46 AM
A non-electric Q-jet has very few adjustments.
First thing is to make sure the engine specs (timing, valve adjustment) are correct.
Then check and confirm there are no vacum leaks.
I set the idle mixture screws (2 small screws at the bottom front of the carb to 3 turns out and begin my adjustments from there..turn them equally and in small increments (1/4 each) and allow the engine to stabilize before turning them again.
I do this by sound, but you can use a vacum guage to determine when the adjustment is correct.
First thing is to make sure the engine specs (timing, valve adjustment) are correct.
Then check and confirm there are no vacum leaks.
I set the idle mixture screws (2 small screws at the bottom front of the carb to 3 turns out and begin my adjustments from there..turn them equally and in small increments (1/4 each) and allow the engine to stabilize before turning them again.
I do this by sound, but you can use a vacum guage to determine when the adjustment is correct.
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