SPEED QUEEN ELECTRIC DRYER, MODEL AES17AWF, purchased 2008
Symptoms: When start button pressed, just hum. Drum motor doesn't turn. Drum motor part number: 511574, motor switch number: 327271
Diagnosis: the drum motor has an attached switch that kick-starts it. When the contacts of that switch go bad, the motor will not run. I made the diagnosis by holding the door interlock switch closed, pressing the start button and spinning the drum counter-clockwise by hand, all simultaneously. The motor would then run normally. I found a repair manual online as a .pdf but it shows the motor switch as unavailable. I didn't want to replace the entire motor just for a bad switch. I decided to see how bad the switch was first. The repair required removal of the front panels and the drum but the modular design made disassembly easy. The only hard part was removing and later reinstalling the belt on a spring-loaded tensioner. That must be done with one hand and I didn't see any easy way since the only access is through the front, behind the exhaust ducting.
Disassembly: Remove the lower front panel (two screws), remove two more to remove the front panel with door after disconnecting two connectors on the door interlock switch. They go to the Common and N.O. contacts. Remove four screws holding the front plate that supports the drum. The metal is sharp... careful! Lift that plate up and off. Two screws hold the top of the dryer... remove those to lift the top up and back on its hinges. Press up on the spring-loaded belt tensioner wheel and slide the belt off. The drum can now be removed for access to the drum motor and its switch. Vacuum out the accumulated dust inside the dryer.
Repair: The switch is mounted on the motor with two T20 Torx (sometimes called "star" drive) screws and has several removable press-on connectors. Remove the main connector. Its end retainers must be pulled out slightly to unplug it. Draw a diagram of the switch wiring before removing the connectors from the switch!!! If a Torx bit is not immediately available, the correct size straight blade screwdriver may be used to remove those screws. Once removed, the motor switch itself has an easily removable cover plate. The switch contacts were slightly burned but I was able to burnish them (rubbed with an old typewriter eraser) to restore normal operation. For easier access, some of the contacts will come out of the switch to expose the contact areas. If too badly burned, the switch would have to be replaced but I managed to get mine going again with minimal effort.
Ray