I have found that some factories never notice the seam in the floats when assembling
if the seam is on the bottom, it WILL leak...much less rate of leaking when the seam is at the top
after 2 bad ones, I started checking all of them
the seam is approx 2/3 of the way along the outside ring of the float ( I think it was dax who clued me into even looking

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