Pump still running but no longer moving water...

Sometimes a shaft can just fail. Metal gets lots of cracks in it when under stress, but if they don't make it to the surface of the metal they seal themselves (people don't realize that perfectly clean metal will bond with itself). If the crack makes it to the surface, then the impurities prevent it from re-sealing and the part fails. This is why shot-peening is used to strengthen metal parts--it makes it much harder for the crack to reach open air, or water, or an oil bath, so it re-seals more often.

The stuff you learn in 34 years of motorcycle riding!

The other suggestions were to save you from unnecessary dis-assembly by ruling out other causes.

Quote:

---

Originally Posted by aylad

Thanks, guys, for all the suggestions......Just an update....my brother finally got the thing apart and the culprit is a broken impeller shaft. There's a plastic piece at the end of the impeller shaft where it screws onto the shaft from the motor, and it's broken in half--so the pump was chugging along with no problem, but the impeller was then not connected to anything and therefore not turning. So--the new impeller with intact shaft is due in around 3:00 this afternoon, and I"ll go pick it up and hopefully (knocking on wood) be back in business when I get it all put back together again.

It's interesting--the impeller in this motor is not like the one in my first motor--the impeller is not a set of blades, but is actually a spinning plastic housing, with slots around the top that the water goes through on its way to the pump--there's not a set of exposed blades that something could get wrapped around,which is what I was expecting. I took some pics of it all taken apart, in case somebody else runs into this sometime... It's been a learning experience, as always...:rolleyes:

Janet

---

Most residential pool pumps use closed impellers these days. I think they are easier to manufacture and don't require as much adjustment as open impellers, plus have a bit more head than open impellers. Unfortunately, one of the downsides to closed impellers is that they are more prone to clogging and usually near the outer end where the vanes narrow. So when they do clog it is not always possible to clear the clog via the eye and need to be taken apart.

Although not too common, this isn't the first time I have heard of an impeller breaking off the shaft which is why I had suggested that could be the problem. If something makes it through the impeller but gets caught in the diffusor, it can break the impeller nut right off the impeller. Also, check your pump basket to see if there are any broken pieces that would allow large debris through. But something narrow and hard can sometimes make it through the basket even if there are no holes.

Just a quick update-- 5 minutes, a $30 impeller, and TA DA--my pump is working again!!!! :D :D

This time, though, the connection coming from the back of the impeller where it screws onto the motor shaft is made of metal instead of plastic, so hoping for a much longer life for this one!!

The good news is that even though the pump was off for 2 1/2 days of 98 degree Louisiana sunshine, once I got it going again this morning and tested the water, I had only lost 3 ppm of chlorine over that time--thank goodness for high CYA levels!!!! So my chlorine was at 4, added a healthy dose of bleach, and we're back in business. What a relief!!

To those who are completely intimidated by taking the pump apart to look for problems, it's REALLY not a huge deal--it's not nearly as complicated as it sounds. I was that way but after this whole experience I wouldn't hesitate for a second to take it apart again if I needed to (here's hoping that doesn't happen!! :) )

Janet