Holley 1940 Idle Circuit
This is the idle circuit of the Holley 1940 1 barrel carburetor.
- Make sure all passages are open. You may have to run thin wire down them to be sure.
- Is the idle air bleed hole open in the throat?
- Is the hole that leads from the idle mixture screw to the bore open?
- Check the idle mixture screw for any signs of damage. Buff the screw with a wire wheel. Any grooves on the tip? Replace it.
- Make sure the Idle aspirator passage is open.
- The idle air bleed does not come out and has a very small passage. Using compressed air make sure it goes through.