6105 noise

[Roy Arena]

I have a pair of 6105's that I purchased from Marine depot. They are exactly a year old. I use the 24v on the power supplies. At full displacement one of them make a clicking or knocking noise. I think it sounds as if it were cavitating but they are placed low in the display. There is no air being drawn from the surface. I routinely soak them in vinegar when they have become coated with coraline. The cover seems to snap into place properly. I see no sign of wear or damage to magnet of impeller assembly. There is a blue washer on the shaft, down in the bottom of the motor housing. Everything looks fine but this pump produces considerable noise at full flow.

Thank you in advance

 

[rvitko]

Is this noise constant or just when turning on? If it is constant, some calcium build up in the pump can lead to cavitation from vacuum inside degassing the water. It could also be some wear of the drive unit or disk. If it is from off an on, either the disk is worn or an additional one may be needed as this is essentially a shim to space the rotor into the magnetic field.

 

[Roy Arena]

It may need a shim then I guess. The controller is set at 30 to 100. The pump does not seem to make noise at minimal flow.

 

[Roy Arena]

Sorry , I meant to say its constant but just as it ramps up. The pump is clean and no sign of calcium build up.

 

[rvitko]

Have you tried swapping the prop/magnet between pumps?

 

[Roy Arena]

I have not swapped prop/magnet yet but I will. I did swap power supplies without any noticeable difference.

 

[rvitko]

The power supply wouldn't make a difference, this will be from a moving part, it is the impeller (only moving part) or the disk is worn and causing some friction.

 

[Roy Arena]

I swapped prop/magnet assembly. The noise followed to the other pump.

 

[rvitko]

OK, it is a blemish or debris in the drive assembly. My first step would be to soak only the drive assembly in vinegar and use a small brush or pipe cleaner in the hole that spins on the shaft, it could be just a small piece of debris or bit of calcium. If it was ever cleaned in a strong acid (even if diluted) it may need to be bored back out, strong acids like muriatic, even when very dilute, will cause the plastic to swell and can also cause this issue as the drive unit will bind on the shaft.

 

[Roy Arena]

I only use vinegar so hopefully the drive assembly will be fine. That is a very small hole. I will try to find a pipe cleaner and give it another bath. Thank you again Roger for all your help. Tunze makes great products and you guys provide awesome product support. Thank you!

 

[Roy Arena]

Disassembled both pumps and soaked drive assemblies in vinegar. Ran the pipe cleaner through the center of both assemblies and inspected. I could not see any precipitation or debris of any kind. Reassembled both pumps, making sure covers snapped in properly. One is dead silent and the other still has noise. It's continuous now, more of a humming. So frustrating. I thought we had it.

 

[rvitko]

Was it always louder or is this a recent change?

 

[Roy Arena]

It was louder before, it seemed to make a cavitation noise at full flow. The pump is humming all the time now. It's different for sure.

 

[rvitko]

Email me your invoice and we will get out a replacement drive unit- Tunze at sbcglobal net

 

[Roy Arena]

Thank you.