4v carb adjustment

leomust68 · Apr 12, 2013

Good afternoon been a while since I've been on here. Finally got the 73 running only problem is it idles too high . I haven't messed with a four barrel so was wondering what I could do to bring the idle down .

wwhite72 · Apr 12, 2013

You might start with the solenoid adjustment.

sm3570 · Apr 12, 2013

Is that the original 4300? There should be an idle adjustment screw.

leomust68 · Apr 12, 2013

Yea it is the original one . I just recently had it rebuilt and installed it just yesterday . The car idles between 1300 and 1400 but once the engine warms up it passes 1700

wwhite72 · Apr 12, 2013

Check the throttle position solenoid.

Bill73Ragtop · Apr 13, 2013

Check the throttle position solenoid.

You should disconnect it at this point. Typically it raises RPM under A/C load.

If idle screws do not have any effect, try a new base gasket. A vacuum leak at the base will cause high idle.

don29163 · Apr 13, 2013

disconnect the solenoid wire, then use the Idle screw on the carb to set the idle to where it idles very low. hook up the solenoid, and give it a little gas so the solenoid pops out, then adjust the idle with the screw on the solenoid.

Note: the choke must be fully open and make sure that the fast idle cam (plastic piece between choke and carb) is releasing.

4v carb adjustment

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4v carb adjustment

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