2 speed Super pump is noisy on LOW speed

[hopkiba]

I have a pump that sounds like a diesel idling on low but normal on high. Any ideas?

[PoolDoc]

It could be a number of things . . . one thought that occurs to me is gravel or something in the volute (chamber around the impeller), and that the gravel is bouncing around on low, but being held in one spot on high.

Cavitation can make a sound like that, but I'd expect it to be noisy on HIGH, rather than low.

If you want to take a video WITH SOUND, and email it to poolforum@gmail.com, I'll give it a listen. Last year, we had a couple of people send videos in, and with both sound and motion, could instantly ID the problem.

. . . membership upgraded.

[PoolDoc]

Your video is here:
http://youtu.be/WS1ocds0AWs

Unfortunately, I'm not sure what the problem is -- I've heard Super Pumps make a similar, but much less loud, noise before. I can guess at several possibilities, but I'd only be guessing.

However, it would be good if you could rule out the possibility of the noise coming from the pump case vibrating against the concrete as a noise source. Just resting your foot on the motor, while the pump was running, should be enough to test that. Likewise, grabbing the piping firmly in your hand, should rule out (or in) the possibility of resonant pipe vibration.

If neither of those are the issue, I'll see if I can call Hayward on Monday. Meanwhile, I'll ask Mark and see if he has any ideas.

[mas985]

That sounds like it could be the centrifugal switch. The switch moves to different positions on high verses low speed so something could be hanging up the switch which creates an imbalance on the shaft. Turn off the breakers to the motor first then remove the end cap. Check both springs on the switch to make sure that they are in good condition and the switch is clean and moves freely in and out. Check the contacts too while you are at it to make sure they are clean. Here is a picture of the switch and springs:

[PoolDoc]

Just gave the URL to J. Phillips @ Hayward Customer Support -- he's going to take a look.

[hopkiba]

Took apart the pump to check the components. Switches, linkages, etch looked ok. There is a spring washer between the bearing and housing that looked worn. When I put it back together, I left out the spring and pump was noisy in both speeds. When I reassembled it, the noise went away! I will get a new spring and replace it if the noise starts again. Any ideas where I can get parts for AO Smith motors?

Thanks for sending me in the right direction!