i've seen a few of these where the governor spring adjusting spring comes loose inside the cover.
I'm not saying anyone would be adjusting this (other than a yale tech) but if you do turn it too far in the wrong direction it will come unhooked from the mechanism inside it.
They have the wire seal on the adjusting screw & nut that should never be broken or missing during normal use, only a yale qualified tech should EVER adjust this setting.

Most of the time i found this wire missing where someone had been adjusting the engine speed to make the truck go faster.
Not a good thing :o/