Noisy Pool Motor

[hbsprite]

I have an AO Smith 2HP 2 speed motor on a Whisperflo pump. It was installed about 4 years ago. I run it on low speed for around 10 hours per day.

A few weeks ago it started making a loud, rythmic humming sound on high speed, which is hard to hear in the video, but on low speed it sounds like there are rocks in the pump:

http://www.youtube.com/watch?v=u58YQBuYfgk

The noise is definitely not the motor vibrating. My water flow and pressure are normal and haven't changed with the onset of the sound.

Thinking it might be debris in the impeller, I took it apart and cleaned the impeller, but there was very little debris there. There are no obvious water leaks and I haven't made any changes to the system recently.

The sound is present 100% of the time. Even after the motor has been off overnight it makes the sound right away.

Any ideas?

 

[Bama Rambler]

Welcome to TFP.

It's most likely a bearing. A lot of times bearing noise will be amplified through the pump and housing. Even if the pump turns free the bearings can be bad and make a noise.

 

[hbsprite]

I thought it might be the bearings too, but everything I have read says that when they go bad they make a screeching or a howling sound! Anyone have a recommendation for a motor shop in the Orange County/Los Angeles area?

Welcome to TFP.

It's most likely a bearing. A lot of times bearing noise will be amplified through the pump and housing. Even if the pump turns free the bearings can be bad and make a noise.

 

[mas985]

What is the motor model #? If it is a CSCR motor, the centrifugal switch may be hitting the housing somewhere. On high speed it may be just out of balance but on low speed it could be hitting the housing or something else. Otherwise, it could be something stuck in the impeller but that should be louder on high speed than low.

 

[hbsprite]

The label says:

Part: 8-177457-02
Type: CXPM Fr: Y56Y

It definitely isn't something stuck in the impeller, as I cleaned that out completely yesterday (there was very little debris in there).

Where is the centrifugal switch located?

What is the motor model #? If it is a CSCR motor, the centrifugal switch may be hitting the housing somewhere. On high speed it may be just out of balance but on low speed it could be hitting the housing or something else. Otherwise, it could be something stuck in the impeller but that should be louder on high speed than low.

 

[hbsprite]

I pulled the end cap off today to see if the shaft was loose (symptom of bad bearings) and it was tight, no wiggle room whatsoever. Also, when I turn the shaft by hand it is perfectly smooth.

If the bearings were bad would there be some play in the shaft or wouldn't it be difficult to move the shaft by hand?

Thanks in advance!

Welcome to TFP.

It's most likely a bearing. A lot of times bearing noise will be amplified through the pump and housing. Even if the pump turns free the bearings can be bad and make a noise.

 

[mas985]

When you said that you checked the impeller, did you just look in the inlet hole or did you disassemble the motor from the pump housing. You would need to do the later to make sure the impeller is completely clear and/or there isn't some loose in the pump housing.

If you have one, the centrifugal switch is on the back of the motor but if you didn't see one when you took the cover off, it may be a PSC motor which some Whisperflos are.

 

[hbsprite]

I actually disassembled the motor from the pump housing.

I believe it is a PSC motor because it says "type : CX" on the label, and according to this: http://www.google.com/url?sa=t&sour...1EHA6IDl5klnrp6E_g&sig2=xYE1ZIht2soGSBemYpVd6A
a "CX" identifier means it is a PSC switchless design.

When you said that you checked the impeller, did you just look in the inlet hole or did you disassemble the motor from the pump housing. You would need to do the later to make sure the impeller is completely clear and/or there isn't some loose in the pump housing.

If you have one, the centrifugal switch is on the back of the motor but if you didn't see one when you took the cover off, it may be a PSC motor which some Whisperflos are.

 

[Bama Rambler]

I'm still betting on a bad bearing. I haven't seen the Youtube video (not allowed to here) but from your description it really sounds like a bad bearing. Spinning the shaft by hand at about 1 rpm is completely different than it spinning at 1750 or 3600.