6000 chattering at 30%

[fkshiu]

Just cleaned the impellor on my 6000. Now when it ramps down to 30% speed, I get a nasty chattering. Took it apart and put it together again, but same thing. Works fine at any other speed.

Any ideas?

Thanks.

 

[rvitko]

Do you have the newer one piece 6100.70 drive unit or the older 6100.60 drive unit with the brake shoes?

 

[fkshiu]

I believe it's the older drive unit since the whole package is a few years old. I'm using the old driver box (7240.26) and the powerhead body is 6100.10

 

[fkshiu]

OK, now that I've had a look at the pictures on your website it's definitely the old 6100.60 drive unit.

 

[rvitko]

OK, that means the brakes are dragging. Either the bearing bush is loose, push it in all the way, or the oring that is on top of the magnetic rotor under the drive shaft is compressed or damaged or the brakes are not fully retracted.

 

[fkshiu]

I've double-checked everything and it's not either the bearing bush or the bottom o-ring.

I do think that it's the brakes not retracting completely as there does seem to be a lot of play (in a circular motion) between the magnet and the plastic collar thing that holds/retracts the brake shoes.

I now actually think that I may be missing a part since in your detail picture of the 7400.620 o-ring in the "How to clean a Tunze pump" sticky thread (the pic below the disassembled drive unit picture with the toothbrush in it) you see an orange ring behind the white plastic ring. I don't see the same orange ring when I look down my drive unit. This is the 7400.620 o-ring, correct?

I don't know when it could have gone missing since I haven't had this pump on a 30% minimum setting for as long as I can remember. I've always run a 40/100 pulse.

Is that orange ring replaceable or should I just get another drive unit?

Thanks.

 

[rvitko]

It is replaceable, you can order it as a seperate spare part they cost about $1.