Microwave, model # jes738wj02

It's normal for it to rotate in either direction. It has to do with the position of the motor and the instantaneous line polarity at the time the power is engaged.

But the grinding noise may indicate a problem...

You can do a quick check. You can see and hear a video of how a turntable motor should sound when you rotate it by hand: http://www.youtube.com/watch?v=rPSWi_z7M58

If yours sounds like it's grinding, etc., you may have a bad motor.

To replace it, you need to unplug power, then remove the bottom cover of the oven.

You can usually find helpful exploded view diagrams and order parts by entering your full model number here: http://tinyurl.com/gv383

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