Suggestion. How I would think about going about it. Get a consensus though as my shade tree is still a sapling.
This picture is for reference only it is not one of our carbs...
The info below was gleaned from the above link.
I wish you would have opened the bowl drains and let a quart or so of fuel flow through. Then closed the drains until the bowls filled up. Walk away for 5 minutes then reopen the drains and let another quart flow through. The idea is have the floats seat the needles. Let the needles be seated for a time, then test fuel flow. This will provide some insight as to the state of the float needles ability to unseat… Anyway, Given that your fuel line is off the 'T' go ahead and
place drain hoses on each float bowl, and position these in a can/jar so to catch the carb cleaner. Open the drains. Insert carburetor cleaner spray can nozzle into the carburetors 'T' fuel inlet port. Spray the Dickens out of that sucker, until pure carb cleaner flows into each container. Reconnect the fuel line and cycle the float bowls with gasoline running at least a quart or half gallon of fuel through the bowls.
Scarier yet, after spraying carb cleaner directly into the float chamber as above, connect a length of fuel line to the carburetor 'T'. Insert the fuel line into the hose of your Wet-or-Dry Shop-Vac. Restrict the vacuum cleaner hose opening with your hand, providing maximum pressure differential to the fuel line and let 'er roar! After a minute or so, restore machine to operational configuration and see if everything is all better (don't forget closing the drain screws!).
"WARNING: DON'T EVEN THINK ABOUT USING A VACUUM CLEANER AROUND YOUR SICKLE IF THERE IS THE SLIGHTEST POSSIBILITY OF ELECTRIC-SPARK IGNITION OF FLAMMABLES. CHECK YOUR VACUUM CLEANER MANUAL."
This should clean out the fuel lines. Look at the collection cans to see what if any garbage came out. The whole point of cleaning out the fuel line is to open them up. You have not tested the restricted flow theory yet. I would do that first. I would think you could open the drains on the bowls (with the catch cans in place) and blow some compressed air into the 'T'. Low pressure at first just to see if you can feel any air coming out of the bowl drains. One at a time too, then both at the same time. This will help you determine blockage restrictions and would be performed in place of the fuel flow test. You stated that the fuel line from pingel to 'T' is full of fuel when the bowls are dry. I take it you have a clear piece of fuel line there? Yes and an in-line fuel filter. Solid fuel on both sides of the inline filter? Anyway, hope this helps.
Again, I am guessing that you have blockage/restriction of some kind between the T and the bowls. Do the flow test. Than you will know.
To keep the float needles from sticking replace them. You cannot recondition the seals. I know the odds of both float needles sticking are remote but both of them sticking would cause your bowls to be dry. (No fuel past the needles) And would also explain the bowls Fuel recovery over time.
