Versa pump running but not pumping.

[Joe31415]

Yesterday I noticed one of my Versa pumps wasn't pumping. I assumed the internal tube cracked, even though I didn't see anything. I replaced the tubes in both of my pumps, one works fine, the other doesn't. The one that doesn't, is still turning, but no water is moving.

I've made sure the clips are tight. I've replaced the tubing again. I've replaced the inlet and outlet tubing, so I know there's no blockages (also, I can blow through them). I've tried running it fast, I've tried running it slow.

I've also disconnected the outlet tube so it should draw water up (from just a few feet below) and nothing happens, so it's not a head pressure issue. I tried running the pump in reverse to see if air bubbles would come out, they didn't. I've moved the inlet to the outlet side and run the pump in reverse to see if that would do anything, again, nothing.

It's almost like the wheels aren't squeezing the tube hard enough, but, as far as I know, those don't wear out, do they?

Any ideas?

Side note: These pumps have been running (and maintained) for a few years now, so it's not that I set them up incorrectly or anything along those lines.

 

[bobnicaragua]

I’ve never had a problem with my versas that replacing the tubing or unclogging lines didn’t fix.

Good write up, it sounds like you covered your bases.

Following

 

[Joe31415]

I've been playing with this since last night and just figured it out (I think). The only thing I didn't try was turning the entire tube assembly around since the metal clips were in the way. Well, I got them out of the way and it started working again.
Here's the culprit:

A hairline fracture in the plastic, which must be allowing in a whole lot more air than I would've guessed.