The pump should kick off no matter what you prop the handle with given it is just another stop like the one on the handle. It does bring up an idea. Each pump handle seems to have its own rate. If we made up a little stop gizmo that was adjustable you could fine a sweet spot with maximum flow and let it run. Many times I have almost made the second handle notch stop work only to have to resort to the slow rate of the first notch to keep the pump running. Something to consider...

Later Ed

In my past life in a gasser I had a piece of double sided Velcro on the tank key chain.  I simply wrapped it around the handle and slid it back and forth to adjust the flow.  

The fueling speed problem on our Beaver is nothing like our HR Vacationer was!  The Beaver is about a sandwich worth most of the time where the Vacationer was more like an afternoon nap.

Pull the nozzle out as far as possible without it coming out of the filler.  Mine works fine, I just get a splash when it shuts off automatically.