I have a brand new Holley 650 Dp. I went to set the floats; first/primary i adjusted just a little no problem there. Now I go to adjust the back float, start to back off the nut and it spits quicker and harder tham my ex-GF.... I go grab a rag; back it off, try to adjust it; but no matter where the scew is the gas level never gets near the lil vision whole.

I also noticed under heavy-constant acceleration one of the secondaries doesnt squirt as fast as the other.

 

sounds like a stuck float if it blows out the vent tubes. tap the rear float bowl with a plastic hammer to unstick it.

 

Do you mean it's spitting from the nut area when you loosen the lock screw? If so, the trick is to slightly loosen the lock screw, but use the screwdriver to keep pressure on the screw and work it in coordination with the wrench you are using to turn the nut. And keep a rag around the nut to soak up any gas that does seep out.

Be careful cause you might be turning the nut too far clockwise and will turn the needle too far in you won't be able to grab the flat anymore. I'd take off the nut and gaskets and set the needle to where 2 1/2 threads are showing.

This is the starting point I like to use on a new needle install. It will typically put the fuel level slightly low. Reinstall the gaskets, nut, locks screw. Then when you go to do the final adjust, turn the nut counterclockwise to raise the level, clockwise to lower it. Go 1/8 turn at a time, then tighten the lock screw while the level adjusts.

If you mean the gas is flowing out the sight hole, might have dirt in the seat of the needle. Just screw the needle out the top and clean it, pop it back in.

I don't like to use those clear sight plugs. They can make the fuel level hard to judge and eventually turn hazy. I've seen guys have the adjutment way off cause those plugs made it so hard for them to see.

 

Take the bowls off the carb. Turn upside down. Set the float so that it's 5/16-3/8 off the side of the bowl, which should be about parallel with the edge of
the bowl. Re-install the bowls.