I replaced one of the gears in our KitchenAid KSM90 mixer. After reassembly (everything fit together fine, no parts left over), when I plugged it in and turned the switch on, nothing. I did not mess with the motor or any of the electrical contacts or switches. So why won't it run?

Mark, December 2007

you have probably placed your brush fittings in wrong. The black screws on the side of the mixer. Look at them and one side will be shiny and inside the hole you will see (with a flashlight) that there is a worn spot on the motor. Match it up on both sides in the vertical position. Then try it. MAKE SURE IT IS UNPLUGGED!

Justbeck, February 2008

Hey Mark,
Here in Dublin, Ireland, I've just done the same repair to
my KSM90 mixer. Replaced the broken plastic worm gear
(bought the spare part off eBay - Euro €16) and re-assembled
the mixer, but no run. Seems like an electrical fault has crept in
somewhere, because the mixer motor was running fine before the disassembly. Checked the mains into the unit, and it's getting power in as far as the power circuit board. Any info you might get on a solution to this would be appreciated.
Bob. Dublin.

Bob Cork, December 2007