My dad donated a rather sick Karcher WV50 window vacuum, water sucky-uppy-thing which he’d taken half way to the bin before thinking, I know, I’ll give it to Matt.
The vacuum sucky-uppy-thing worked of sorts, but when operated, made a noise not to dissimilar to a distressed cat riding a trolley with wobbly wheels, if you get what I mean. I wish I’d recorded it.
Anyway, opening up the WV50 was pretty straightforward. Just several crossed-head screws held the two plastic halves of the unit together, revealing a simple electronic board, battery, switch, motor and fan with exhaust.
The principle of the WV50 is the same as any other domestic vacuum cleaner. A fan drives air in one direction through a smaller hole (exhaust) creating a vacuum, in this case at a small wiper blade for glass cleaning. Water is then drawn towards the fan, with the vacuum created and then diverted to a holding tank, for emptying later.
The tank on this product is quite crude and I suspect that should it be knocked over, the water within the tank could spill over in to the exhaust and in to the motor. This is what I suspected had happened and caused the motor bearing on this device to wear excessively, causing the noise.
The cost of a motor and fan replacement on the WV50 was about £30.00 (where I saw them listed) but this would make the repair un-economical. After an email conversation with Mabuchi, the makers of the motor, the original equipment K-280SA-3525, unique to the WV50, was no longer being made.
I don’t like being ‘beaten’, but having spent far too much time with batteries, bulbs and motors as a child than is entirely healthy, I realised that the casing and bearing on the K-280SA-3525 was pretty standard fare and if the spindle on our motor was OK, then all that would be required would be a new bearing. It turned out that the spindle and motor brushes were OK, so I ordered a same size motor from eBay, via a very efficient and friendly Chinese electronics specialist with the intention of swapping the motor body and bearing over.
The motor arrived quickly and the transplant only took a few minutes. Once reassembled, the motor and fan sounded like new once again. A nice cheap fix, to keep this vacuum cleaning windows for another day.
I even made a short video, showing what I did. Enjoy.
Cost of replacement: £50.00 (equivalent model) Cost of repair: £1.50, some international emails and a couple of cuppas. Nice.