Flooding on an Edelbrock carburetor is a situation where the float bowl is getting too much fuel and it is pouring over the top.
Some of the causes, not in any order.
- Fuel pump pressure - test your fuel pump. New pumps are especially suspect. Should be 4 to 5 lbs.
- Bad float - heat some water and immerse your float. Bubbles would indicate a leak.
- Float sticking - gently move the floats up and down to make sure they aren't sticking somewhere.
- Worn float pin
- Needle - Putting any pressure on the needle when adjusting the float can damage the viton tip and then it will not seal. Test the needle and seat.
- The seat uses a metal washer and they don't always seal. Unscrew the seat and screw it back in will help. Turn the top upside down with the floats resting on the needles. Blow in the inlet gently. You should not be able to blow through.
- Float level - Should look level with the top upside down.
- You may be getting dirt in the needle & seat - this could be caused by a dirty, or old gas tank. Ethanol is a great gas tank cleaner. Unfortunately years of built up material on the inside of the gas tank will be sent up to the carburetor.
Off road - you may need a spring loaded needle & seat.