K-A mixer disassembly
Taking the rear cover off only gives access to the speed governor. Also, the two plastic screw-on black plastic buttons, one on each side, access the motor brushes. If they're worn too short, the motor will lose power and eventually not work at all. Very easy replacement, just make sure the curved surface of the brush follows the curve of the mixer body. Getting the top off is harder; you must remove the screws on the underside and drive out the pin which secures the rotating disc (which has the shaft sticking out where you put on the beater), and pull it off the shaft before you can open the gearcase. A note about quality; unlike the K-A dishwashers, which decreased markedly in quality when Hobart sold them off, the mixers appear to still be built as robustly as they were back in the Hobart days. I have a 2002 Ultra Power, and I swear you could winch a car out of a ditch with it. I routinely mix bread dough with it, and it barely breaks a sweat. I still don't think anyone makes a better one.