Dropped my MP40wqd, now it makes noise :(

[Greenjeans]

I was moving my power heads around, trying to eliminated dead spots, and dropped an MP40wqd dry side. Now it rumbles slightly, like the shaft is wobbly or something.

It's less than a year old, but with the current warranty situation, it could be a long time before I ever get it back if I sent it in now...and do they cover drop damage?

I'm sure it'll prematurely wear out if I leave it how it is, making noise, so I think I'll be disassembling the dry side...I'm hoping I simply knocked a bearing loose and I can press it back in place. Otherwise I'll be noting part numbers and ordering replacements.

Tips before I tear it apart?

https://www.reef2reef.com/threads/has-anyone-ever-rebuilt-an-mp40-dry-side.348951/#post-4343091http://www.reefcentral.com/forums/showthread.php?t=1901337

 

[Greenjeans]

I took it apart, it was easier with the wqd than in those videos, no prying or cutting involved.

I cleaned and inspected the rotor and stator, and checked both of the bearings - they looked fine and didn't have any wobble or angle to my eye the various ways I checked. The rotor had a couple slight nicks, but nothing of concern.

I reassembled it and it still has a slight rumble, no change :(

I ordered a set of replacement bearings, so I'll swap those out next. Both sides use 608Z (zz) for what it's worth, so very common...I went with some fancy skate brand :)

 

[Greenjeans]

I swapped out the bearings today with Bones Reds, the whole process went off without a hitch. The trickiest part was supporting the bearing while tapping the axle out, but I managed without damaging anything.

After reassembly there was a slight noise as the magnet coupler sat a little too close to the motor housing (maybe I tightened it down too much?), and would occasionally touch. I added one of the "speed spacers" washers that came with the bearings, problem solved.

First impressions - it's not as quiet as the other MP40 that wasn't damaged, but is much quieter and smoother sounding than it was before. The bearings are obviously much nicer than the original ones, and spin much more freely. I imagine it will get quieter as it breaks in over the next few weeks...I'm happy!

I'm tempted to swap the bearings on the undamaged power head, but if it ain't broke...at least I have some on hand in case the bearings do go bad.