by StevenHB
(Boston, MA, USA)
At the end of last summer, my Deluxe 4 stopped moving. Clearly the impeller was working because I could see the water circulation it was causing at the surface of the pool. With some help, the problem was diagnosed as a failed hex adapter (I can't imagine how it happened but one of the arms on the U that grasps the drive shaft had splayed open so that the drive shaft no longer turned the adapter).
About $15 for a new hex adapter and a few minutes to take the thing apart, install it, and reassemble it, all is good. I regret not taking a picture of the failed adapter before tossing it.
Still wondering about how the adapter failed (but I'm sure glad that it failed, protecting the motor assembly), it's pretty sturdy.