dishwasher problems

Hello,
My dishwasher stopped working. I posted to the ukwg web site and someone suggested that water ingress had seized the bearings on the motor.
When the motor was in situ I could not turn the impellers. Once I removed the motor, I could turn it but it was hard work. With the impellers removed, I could not turn the spindle.
I thought if the motor was seized it would not move, so I am puzzled how I managed to turn it but perhaps I was applying more torque than the motor could (is this possible?)
I've only had one person help on ukwg, so I thought I would post here for a wider audience. To be fair perhaps the repairmen are out at work.
I took a few photos which I uploaded: http://tinypic.com/r/fnegx2/6 http://tinypic.com/r/sp9qbb/6
There didn't seem to be any obvious water ingress until I removed all the impeller assembly and then I found a sandy/dusty substance. It is not rust. What is it? Scale? Some sort of corrosion?
It was suggested that the IWMS might be a problem in the future and I would be better buying a new machine. There are some deposits in the IWMS; I believe they are mould. It is in the water inlet side of things, so it is not dirt from the washing.
http://tinypic.com/r/awtdno/6
Thanks, Stephen.
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It happens that Stephen formulated :

The rusty coloured white dust is limescale, so it looks as if the shaft and bearing at least have been sat in water. Whether or not it should be I don't know, but what I can say is that the motor shaft should turn quite easily by hand. The fact that it doesn't, suggests the bearing(s) have been damaged. You may be able to pull the motor apart and just replace the bearings sourced from a bearing supply company, but would need to sort out the leak before reassembly.
That type of motor will not produce much torque from zero RPM, its best torque will be at or close to full speed.
--
Regards,
Harry (M1BYT) (L)
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On Wed, 22 Aug 2012 18:31:27 +0100, Harry Bloomfield

Thanks for your fast reply. I did wonder if it might be scale but I thought the dishwasher softened its water, so I thought there would not be any scale to precipitate?
The motor is not designed to sit in water; it is under the machine exposed to the room, so it could not sit in water unless it flooded. Beneath the motor is a tray with a polystyrene float which should cut off the machine if the machine did flood.
I think that the rubber seal between the sump and motor has allowed a drip to escape from the sump but this should be soft water, so I am puzzled how it has deposited scale.

Thanks. I hadn't held a motor before so I had nothing to compare it to. It certainly seemed stiff but I wasn't sure if they were all like that.
There is also a split in the spindle. I don't know whether that is significant?

Perhaps getting new bearings would be cheaper than a new motor (100) but although a dishwasher is not a life or death machine, once you have got used to one, you miss it when it is not there. It might be quicker to pay for a new motor and get it delivered the new day rather than spend days looking for somewhere that could repair it. This motor comes with new seals and a new impeller, so hopefully the new seal would fix the leak problem.

Thanks. I didn't know that; I've learnt something new today.
Thanks again, Stephen.
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