Fixing a sluggish blender | How To Repair Your Old Blender?

A blender's motor turns a coupling that drives mixing blades inside a food jar. The speed of the blades is governed by a switch. On some blenders there are as many as 14 switch buttons, each of which sends current to certain copper windings inside the motor; the more windings energized, the faster the motor shaft turns. On models with a high/low button, a simple electronic device called a diode reduces the current to the motor when the button is set on LOW.

Sticky liquids often find their way into the cracks and crevices around the buttons, jamming the switch. If you cannot loosen stuck buttons by tapping them, replace the switch, taking careful note of the wiring pattern.

If the motor seems to strain, check the mixing blades; they should move smoothly when spun by hand. If they are sluggish, replace the assembly to avoid damage to the motor. If the motor does not run, is especially noisy or smokes, examine the copper coil for burned or discolored windings; but burned wires at the ends of the coil are just the normal result of soldering.