Hi,
I have probably a simple question for many of you in this board. I have a holley carb 670. The primary bowl is adjusted correctly, but the secondary bowl the level of fuel is too high. My question is if lowering the float level down (clockwise), is will that bring the fuel level up or down? It seems to me that it will displace the fuel upward.

any advice is appreciated. Thanks.

 

With the car running, loosen the slot-head lock screw VERY SLIGHTLY (too much, and fuel will spray everywhere; odds are, some will leak regardless), and WHILE HOLDING IT STILL, turn the big hex nut clockwise to lower the fuel bowl level; then tighten the lock screw back down. Going that way pushes the seat of the needle valve farther downwards.

You'll find that if the fuel level is too high, it probably won't go down on its own, while idling. After all, unless the secondaries are operating, no fuel is being extracted from that bowl, unless the carb has 4-corner idle which I doubt your carb has. Best way is to set it way too low (like, 2 full turns inward), go drive it around using the secondaries to drain it, then come back and raise the level (ccw on the hex nut) from there, until fuel is maybe 1/16" - 1/8" below the sight plug.

 

Thank you sofa!
just so i am clear, when you say 2 full turn inward, you mean clockwise on the hex nut? Then after driving come back and slowly raise the float (counterclockwise).

 

Yes.

 

Great thank you!

 

Good morning,
Quick follow up: as I did the adjustment, I noticed my washer became disintegrated. So I removed the screw and the locking nut and inspected the needle. The needle seems to be sticky. I bought a new one, but my question now is what is good place to start? Meaning how deep should I drive the needle and the nut?

Thanks in advance for any recommendation.

 

Turn the carb upside down and watch the float as you install the seat. Let it lift (i.e. push down, when installed) the float about ¼". It should then be somewhat too low, and you can adjust it after you start the engine.

 

Thanks sofa. Any recommendations to set up with the carb installed? If not, then I will remove and follow your recs.

 

That's pretty much the best way I know of to preset a float level, short of taking off the fuel bowl. Which is often a royal PITA due to the gasket sticking to the castings.

 

Fair enough, thank you!