Quote Originally Posted by hemmjo View Post
I just tried it. When I was walking to the pumps, I realized that my trusty orienteering compass will not work. All of this type of pump, the ones I know of anyway, have to be mounted so the shaft is horizontal. All of the compasses I know of need to be held so the needle, or plate is level. When you try to hold it against a pump base, the needle tilts and cannot move.
Could, aside from not being horizontal, it be from the excess diameter of a orienteering compass? (Lol, maybe only 15 guys here know that term). It may not wish/ be able to sync with motor poles, like the little one shown. Also, the Grundfos model spins a card, not a needle, possibly larger bit of iron too, hence better balance, easier turning.

Now, anyone have a keychain or zipper tab compass and a vertically positioned motor about the premises,......?

A quick web check found them at low cost, starting about $6.00 USD. Pretty cheap insurance, being applicable to vertical motors in general. And a lot of motors have very short tolerance to running counter to whatever their design rotation.
Anything to avoid purchase of full fledged rotation meter, ie Biddle, Fluke, Amprobe, Ideal, and many others. $125 and up; WAY up.