6055 and 7094 Question

[iaJim]

I recently purchased two used 6055s and a 7094 controller on ebay. I got them yesterday and installed them and am very pleased with the current and the way it is controlled. When I installed them, I noticed they were not silent, but figured that must be the way they run, but overnight, one or possibly both of the pumps became noticeably louder. I get a vibration buzz when the switch from full power to partial power. Is this par for the course, or do I need to do some maintenance on them?

These are pumps that I think you may be familiar with since the previous owner told me that Roger had sent him new shafts and somehthing else for them.

Thanks for any help you can offer.

[rvitko]

The shafts cannot be replaced, so we wouldn't have sent him new shafts, the only part may have been new drive units and disks. If they dry up with some slat and detritus inside they can become quite noisy, they may just need to be thoroughly cleaned. They should not be loud.