Question on Holley power valves

[spstan]

I have a Holley 4175 spread bore carb that's been flooding. 1) Floats are OK; don't leak and are adjusted just below parallel. 2) Needle and seats are OK; hold air when I hold up float and blow through tube attached to fuel inlet. The only thing I could think of was fuel pressure. But before I invest in a fuel pressure regulator I'm wondering if I haven blown the power valve

My understanding is that newer Holley power valves aren't as susceptible to blow out. And I'm also wondering how a blown power valve could cause fuel to drip from the bottom of the EVAP cannister (fuel has to be pretty high in the bowl for this to happen).
Any thoughts? Which would you do first 1)check the power valve (and how do you do this?) or 2) invest in pressure regulator. Paul

 

[CBODY67]

Blown power valves do NOT affect fuel level, period. Just a bit rougher running and poor fuel economy. Think "air/fuel ratio at 12:1" all of the time.

 

[volksworld]

are the floats brass or plastic foam? cause the foam ones can absorb stuff from the fuel and become non buoyant...blown power valve will suck fuel through it and run rich but it won't affect fuel level in carb

 

[RemCharger]

Needle +seats.

 

[spstan]

Needle +seats.

Ram; held the float up and blew air through a tube connected to fuel inlets. Needle and seats (both bowls) sealed with no air leak. Floats don't leak and are adjusted just below parallel. Next step is a fuel pressure regulator; all I could think of. Paul

 

[Toolmanmike]

Check your fuel pressure. Regulate it to about 5#.

 

[RemCharger]

Ram; held the float up and blew air through a tube connected to fuel inlets. Needle and seats (both bowls) sealed with no air leak. Floats don't leak and are adjusted just below parallel. Next step is a fuel pressure regulator; all I could think of. Paul

Had to look up the carb. Figured it had the standard 4150 adjustable needle and seats but no.
Nor does it appear to have sight plugs.
Yes a pressure check would be a start. But if you had a standard fuel pump it would certainly be odd that it ramped up pressure beyond regular values.