Idle air screws

[gick70]

Holley carb,tuning my carb with a vacuum gauge,I,m getting a lot of change with one screw but not so much with the other,what gives? Blockage??

 

[rmk57]

Float level to high, blown power valve if it's an older Holley, to much idle transfer slot exposed. Has to be pulling fuel from somewhere.

 

[SHX669]

What RMK said --
Which Holley carb ?
Are you turning one screw 1/4 turn at a time then going to the other ?

 

[Seventee]

When I've run into this issue, it means the air bleed for that side is plugged. I clear it up by removing the idle screw (keep track of the little seal!), and giving the circuit a few short blasts of compressed air. Then I do the same back through the air bleeds, which are the tiny tubes poking out of the top of the carb.

This isn't to say something else isn't a problem, but it's an easy place to start.

 

[blubuckaroo]

When I've run into this issue, it means the air bleed for that side is plugged. I clear it up by removing the idle screw (keep track of the little seal!), and giving the circuit a few short blasts of compressed air. Then I do the same back through the air bleeds, which are the tiny tubes poking out of the top of the carb.

This isn't to say something else isn't a problem, but it's an easy place to start.

X2.
Gasoline deposits can build up in the air horn and plug up the air bleeds.
I found a long nylon tube for spraying carb cleaner into tight areas. I pull the air bleed screws, and hose the ports out.

 

[B RON CO]

Hi, X2, as long as there is no vacuum leak on that side of the plenum, as in a leak at the manifold to head gasket or warped carb base, or something like that. Good luck