Leaky float valve in BE03AC Honda Carburetor

I've got a Honda SX214-SXA mover. I was doing my pre-season servicing which included draining the carburetor bowl. When I saw the particulate matter in the bottom of the bowl, I removed the bowl and cleaned it out as best I could. I also pulled the float valve and float for inspection. The float valve looked OK. When I put everything back together, the float valve did not seal and the carburetor leaked gas.

I got a new float and float valve and installed them. No improvement.

I have a spare carburetor which I compared with the leaking carburetor. Turning them upside down, I could see that the float on the spare carburetor was just a little bit higher than the float on the leaky carburetor. I re-installed the original float and float valve and the leaky carburetor again had the lower float height. Of course, there is no float adjustment.

What's puzzling is that the leaky carburetor did not leak for over 20 years. I suspect that it was marginal when new and moving parts started the leak. I'm just surprised that new float and float valve didn't cure the problem.

Has anyone experienced the same problem with a Honda carburetor? Could I slightly stretch the spring on the float valve to get a little more pressure on the float valve?

Leaky float valve in BE03AC Honda Carburetor