Oops! It wasn’t the West Marine rolling ball switch. This just shows
the value of testing things over and over. I pushed down on the West
switch in this two switch setup and the pump stopped. The system also
worked when the bilge level was drawn fully down below the West switch
so I drew a conclusion.

I raised the switches today and had the same problem. It’s not fully
repeatable and pushing on the West switch before must have just
happened to be at the same moment the system cut off by itself.

I’ve now done it over and over and over and over with multiple repeats
of the same malfunction.

Conclusion:

I have a Rule mercury float switch that shorts ON in an intermittent
and flaky fashion. When the pump keeps running, the only thing that
will stop it is wiggling and cycling of the Rule switch. No amount of
wiggling of the other switches or wires will duplicate the problem. It
isn’t the relays in my set up because it works exactly the same with
them pulled.

Has anyone else heard of a nearly new Rule switch acting like this?

Apologies to West.

--

Roger Long