WD carb help needed

I picked up a WD not that long ago and I am having some issues and I am probably missing something simple so I figured I would go here with all the expertise and fresh minds. The issue I am having is that the tractor will barely run with the choke off; runs okay for a few seconds then dies down and the governor opens right up for it to recover. With about half choke it will run okay with just a little miss. I have good spark, have cleaned the carb (all passages with wire, carb cleaner, and air) and set the screws and checked float height to original specs, blew out the line and sediment bowl and made sure I have good gas flow, and used starting fluid while running to check for vacuum leaks and haven't found any. It seems to be a lean condition as partial choke allows it to run but no matter how much I adjust the mixture screws it makes no difference as to how it runs. The only possibilities I can think of right now are that the power screw has some corrosion to the point of having some pitting. I have cleaned it up but still has some pitting. Also the float as indentations on the outside faces that I'm not sure if they are meant to be there or if it is dented. The float doesn't leak and it seems like if that was the issue it would be flooding not too lean. It has the Marvel Schebler TSX. Thanks for any thoughts.

I would look at the venturi and see if it's fitting tight, then go from there. Sometimes the lips crack or even break off. If cracked just solder them up on the back side. I've seen the lips get bent and this causes an internal leak.

I did run it with the air cleaner hose off and same deal. The venturi is in good shape and does fit the carb but always comes off with the gasket, it doesn't fit really snug into the carb body. Should they press in tight?

I have blown out the line and sediment bowl and I have good fuel flow through the hose at the carb. It did have a filter but I also tried it with a regular piece of hose and it didn't make any difference.

While it was running I sprayed the seals where the manifold meets the head with starting fluid and it made no difference to the way it ran so I don't think I have a vacuum leak there either.

I have tried adjusting the screws beyond the original starting specs as I usually have to on all my old tractors to tune them in but no matter how much adjustment I use it doesn't make any difference. I can make three or four full turns on the power screw and it has no noticeable effect.

Have you tried running with the gas cap loose as per someone's suggestion?

You can test the float by holding in down inside a cup of warm water. The warm water will warm the air inside the float and pressurize it. If there is a leak you will see the bubbles coming out of it.

If the float were leaking your tractor would be flooding. It seems you have the opposite problem.

The venturi coming out with the gasket is OK. It seals on the ends. So if it happens to be short, then you can loose some of the suction where it draws gas into the engine. It doesn't sound like that is your real problem but is always a possibility.

Well I pulled the carb down to pretty much the cast iron case and re-cleaned everything and it still runs the same. I did check and the throttle shaft has noticeable play in both directions, side to side and in its bore. I think my next step is get a total rebuild kit for it with new float and throttle shaft and totally go through it.

This piece needs to be removed and cleaned.

Soaking isn't always enough. Sometimes the passages need a good brushing with a wire brush or high velocity sand blaster to move the junk softened by the soaking. Rust is harder to move.

Gerald J.