vacum advance problem

[72golddustermike]

problem is if u rev engine it does not want to return to idle speed. if i un hook vacum advance and plug port on carb it acts normal. i hav triple checked linkages they are no the proble could vacum advance be sticking

 

[67Dart273]

Put a vacuum gauge on the hose to the vacuum can?

 

[KitCarlson]

A mighty-vac is helpful. It can measure the vacuum on the hose when T'd in line, or used to provide a vacuum source for testing dashpot operation and leaks.

The vacuum port that connects to the dashpot should go to near atmospheric at idle. A wrong port, or too high idle setting may provide vacuum at idle.

 

[72golddustermike]

bouncy 7-10 on vac gauge both ports adjusting idle mixture screws has no effect. took carb off there was no adapter plate under it. intake is a performer. could not having that plat mess with the idle circuit?

 

[67Dart273]

ONE of the ports should be "full vacuum" and THAT is a very low reading. You have the idle screw (speed screw) screwed way up? Big cam? Where is the initial timing set?