Dyer will not start hum when pushing start button

ALWAYS UNPLUG YOUR DRYER BEFORE ATTEMPTING TO DO ANY WORK ON IT.
Sounds like your problem may be a broken belt, or the belt may have slipped off of the motor pulley, or idler arm pulley.
If you have to check/replace/repair your drum motor,drum seals,belt,rollers, etc.
If replacing drum seals be sure to use a good grade of weather proof cement to hold the seal/s in place.
Note: This method works for most front loading machines.
Remove the electrical console that holds the timer switch, start switch, etc. from the top of the dryer. Be real careful not to knock any of the wires off of the timer switch or other electrical connections.
Remove the lint filter and the screws that hold the filter housing.
Then remove the top of the dryer.
Note: Some of the tops tilt backwards and do not have to be removed completly.
Remove the front of the machine, this will expose the belt and drum, remove the drum and belt and this will expose the drum rollers, idler arm bracket with pulley, and motor with pulley. Pay attention to the route of the belt, this will come in handy when you go to reinstall the belt and drum.
Sometimes the belt will slip off of the idler arm or motor causing the drum not to turn.
While you have the drum out, I would recommend that you lubricate the drum rollers at the shaft of the roller with a good grade of machine oil like 3 in One oil. This will save you a problem later with the rollers getting noisy, also check your drum rollers for flat spots, if they have flat spots on them this will cause a noise like a thumping type noise. You will need to replace the drum rollers if they have flat spots on them.
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