Originally Posted by 
bee utey
				 
			The short answer is that someone clearly has for some reason unscrewed the brass outer section after testing the carby, probably while undoing the fuel pipe. When screwing it back in they weren't careful enough to hold the needle and seat level or uphill while screwing it back in. Just put the needle, pointy end towards the seat, in the outer bit and carefully screw it back in. Then with your finger tip maneuver the float against the needle so it's gently closed. The top face of the float should be near level, there's a measurement in every Holden workshop manual but you should be able to find it online.
Fuel pressure opens the needle, no spring is needed.