Possible pump motor bearing failure?

No suction gauge.

I don't know if this observation would be comparable or just convolute the issue. I have a navigator vac that until this problem, for it to get into the flow spec per the hayward gauge: I would turn both skimmers off and drain valve 1/3 off, so the navigator would have max flow.

With this problem occurring to see if I could get the thing to sweep at all, with the drain almost closed off, skimmers completely shut down, could only get to low end of the hayward flow gauge...

Will see if I can locate an actual suction gauge.

Yes that can be very relevant. Do you have the same problem without the cleaner and with the skimmers and main drain fully open?

Reducing the flow too much to the pump can be problematic.

Quote:

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Originally Posted by kballard72

Will see if I can locate an actual suction gauge.

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Dixon Valve GL105 2" Steel Lower Mount Compound Vacuum Gauge @ Amazon

2 days, if you have Amazon Prime. You may also be able to adapt an automotive vac gauge, available at Autozone or some such.

Quote:

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Originally Posted by mas985

Yes that can be very relevant. Do you have the same problem without the cleaner and with the skimmers and main drain fully open?

Reducing the flow too much to the pump can be problematic.

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What I am mean is that under normal circumstances, per the builder, was to turn the skimmers off when vacuming.. That always got the flow gauge for the vac to the low end. For 3 years. Just tweaking the drain a little, not all the way to a 3rd would get it to the high side of the gauge...

All I am saying is that since this problem started occurring, if i hook the gauge up to the vacuum port, skimmers closed and the drain almost completely shut off will get it the gauge up to the low/mid point...

While it may not seem probable, the only thing left is diffuser, o ring in the diffuser, o ring on the lid...

no air seems to occur before the pump on suction side (plumbing issue)

the motor when removed is quiet as a mouse.

Sooooooo out of ideas at this point.... unless there is a hail mary... the robo vacuum already tells us we are losing suction power.. on High, with valves fully open no robotic movement. close skimmer, almost close drain, and robot barely moves.

Any final hail mary...

Again, does this only happen when the cleaner is attached and the suction ports restricted or does it also happen without the cleaner and with all suction ports wide open? This is a very important distinction.

If it is happening only with the cleaner attached, the cleaner hose maybe collapsing which is causing the oscillatory condition. Try removing the cleaner all together and open all suction ports and see if this continues to occur.

The problem happens under normal usage. skimmers on, drain on, returns on.


The cleaner port is simply an example of one place I do have a gauge for. With a single 4 foot hose plugged to the port, and the flow gauge on the end, I can see that it is not drawing the suction it was say a month ago... But that is only to SEE what it is doing. The vac is not the issue...

Diffuser came... having a point of reference, new versus old... it was clear the old one was worn. Where the wear ring butts up against the difuser used to be a ridge about 1/4" wide by 1/8" tall, not only was it gone but it was a valley on the diffuser.

SO, I thought viola, this is the problem we have been looking for... Replaced it... kicked on the pump all is wonderfully quiet as usual on start up.... basket fills up, all air purges... nice and clear window.... and 5-10 minutes later, so long pressure, hello irritatingly loud chatter....

thanks for all the insight, but it must be time for someone on-site I guess...

Unless you got that vacuum gauge. ;)

BTW, does the flow rate out of the returns decrease or increase when the pressure drops?

it definitely decreases. as well as the water feature, which is simply two returns on the sun deck that point straight up.. they drop from 2 feet high down to 6 inches....

For that wear ring to have carved away an 1/8" of plastic off the inside of the diffuser, is that a normal amount of wear?

Well clearly there were items worn out and they have all been redone, and seems to be casualty symptoms of something else going on. Impeller, wear ring, and now diffuser. All of which were visibly worn with the diffuser seeming to be abnormally chewed up. Either way all internal parts except the motor are shiny and new.

The odd thing is the split second change, as if something "gives" like suddenly the pressure is just gone... Its not gradual... after being off for awhile you can turn it on, all will be well, than bang, pressure dives and noise starts.

The noise which sounds like rocks clattering, is what I have read to be the sound of cavitation. So that may just be s symptom of the pressure drop and not the cause of it. One way I have found to make the noise stop is restrict the returns to cause the pressure to build up some. I dont leave it like that, just something I noticed.