I'm pretty sure this is normal. The plate is "stuck" open because of the idle speed screw sitting on the idle cam. As soon as you tap the throttle it will shut.
You could check the push rod between thermostat lever and choke plate-trinagle - and aswell the other one -conecting the vacuum plunger and the triangle. These rods have small tabs that are securing, that the rod can´t fall of during operation. (to disconect, you have to turn them into a position, where the tab matches the notch in the hole of tringel-plate. There are chances, that you mount the rods in a way, that the tab can slip into the notch of the plate (if the whole system is put into a certain position). Then the choke plate will be stuck and can´t shut to the specified position. When wiggeling around you will free up the tab from the notch and evrything will be working as supposed. I´ve had this issue and it was hard to find. Check your video at 2:45 and 3:35 - Not shure, but it could be, that you´ve got this problem. if so, trie to turn araund the rod - up side down and/or inside out (you can aswell stick the rod from the backside through the triangle plate. Search for a combination, where tab and notch are clearly positioned in different directions. By the way: make shure; that you adjust the gap of your choke plate by the correct way. It looks, that your carb has a vacuum device. In this case you will adjust the gap by bending the connecting rod to the wright length, while the plunger is fully seated (like it is, when motor is runing). You will find viseos about that. After you have adjusted the gap, you turn the thermostat clockwise until the intermediate rod is pushing the choke plate to it´s defined position. The further you turn the thermostat - the later the thermostat coil will open the choke plate (the mixture will stay richer). Hope this will help you - would be great to share any results or thoughts
You have a electric choke on that carb. Turn the key to the on position an the choke should heat up and open a coil that sets the choke. Let us know how it's going, cheers!
@@MrAndrewdouv great video just in the process of setting one of these carbs up,great info trying to get the choke working,the wires are going to the coil and there's only one plug on the choke and two wires from the old carb on a 79 470 merc.