Stream 6000 vibrating at low RPM

[IsaaX]

Just recently I've been noticing that one of my two 6000's has been making a vibrating sound when it pulses onto the low rpm range (30%). While the pump is operating in the display, I can feel the pump vibrating/shaking with my finger. It feels like the impeller assembly is rattling in the pump housing at low RPM's. generally in the front grey bushing area. There is some play but I am unsure if that's normal. I can wiggle the impeller around within the inner diameter of the front bushing. The pump is a couple months old and I have tried cleaning it with vinegar and a toothbrush. I've also turned the front bushing 180 degrees and I still get the vibes/rattles. My other 6000 does not do this at all and is the same age (2 months). When i put my finger on it, it does not shake or vibrate. Do you think the front bushing is worn?

I do use the MultiController to control both pumps.
Pulse Interval = 2
40sec Duration
30%/100% pulse on both pumps.

I'd like to get a handle on this asap cause the vibrating sound my wife and I hear gets annoying at night. Only heard when it pulses at 30% power. Bzzzzzzzzzzzzzz

 

[IsaaX]

Also, if you think it's the front bushing being worn, I can pull out the other pump and swap bushings to see if it makes a difference?

 

[rvitko]

Likely the bushing is just worn a bit, I can send a new one. Due to the hand assembled nature of the pumps though their can be differences of up to about 5% in speed, if you have a pump that is really doing 25% this would explain it as well and simply turning the knob up very slightly would also remedy the issue.

 

[IsaaX]

Thanks for the quick reply Roger.

YGPM