Tunze 6055 is making rattling noise

[DiscusHeckel]

Hi Roger,

I may have the same problem as the one described in this thread.

My Tunze pump is an old design, which has a fixed metal shaft. The shaft has come lose lately. I pushed it down, but whenever I remove the impeller it comes off and it wobbles. It feels as if the plastic end bit is not grabbing the shaft tightly enough. Moreover, during operation, the impeller seems to be touching the housing, thus causing vibration. I am guessing this is because the shaft keep wobbling. I pushed a 6055.740 (bushing and attenuation disk through the shaft. However, the blue bit is too big to get into the hole. I cannot remove the black bit at the bottom from its housing anyway.

What part do I need if there is a solution please? Would I be able to remove the black bit using a large screw or do I need a special tool? I did not quite understand the tool you mentioned in the other thread.

Thanks in advance.

DH

 

[DiscusHeckel]

Hi again,

I have just phoned Tunze wholesaler in the UK to explain the problem and possibly get a spare part.

What they said to me was that the shaft was embedded in a resin in the factory. It should not have come off. Once it comes off, I cannot repair it and the only solution is to get a replacement motor head :sad1:. They asked me to fix the shaft by using a 2-part epoxy.

Have I been given the right advice?

Thanks

DH

PS. I seem to have lost the metal disk while cleaning the pump.

 

[rvitko]

That is correct, the shaft is actually not fixed in resin when new, it is pressed into a hole that is half the diameter of the shaft with a lot of pressure. If the fit is tight enough that the shaft can be seated, I have found the best repair to be drilling a 2mm hole in the existing hole, only about 1.5-2mm deep so you don't drill through and applying a drop of superglue to the shaft and quickly pressing it in further so it presses into the newly drilled hole as well (deeper seat). Otherwise replacing the motor is the best bet.

 

[DiscusHeckel]

Thank you Roger.

 

[DiscusHeckel]

Hi Roger,

A friend of mine came to my house to sort out my pump tonight. He followed your instructions and drilled a 3 mm hole in the rubber using a tiny drill bit. He operated the drill bit by hand for precision. After securing the shaft into the hole with a very small amount of super glue, the shaft felt stronger than ever. I pushed a bushing and attenuation disk (6055.740) through the shaft and then tested the pump, it has never run quieter.

Thank you again. Your advice is second to none.

:beer:

 

[rvitko]

Glad you could fix it. The shafts are now pressed in much deeper and have been since 2008, the first ones the shaft was not pressed as far so this issue was more common.