I found the fuel line for the clunk had somehow gotten stuck to the top of the tank, so the clunk was only hanging down about a third of the way in the tank..

I would have clamped everything, but the outer diameter of the lines inside the tank seem to be smaller than normal.. guess I will replace them sometime soon to get rid of the no clamp problem.. The bubbles went away once I fixed the stuck line... and the adjustment now holds true...