Turning motor failing

Question

Hi,I have the Westpoint TV-258 (claims to be 1,200 W) white microwave.I need some guidance on opening and I suppose repairing the turning motor under the microwave.Problem:The motor is sputtering and at times is making a noise. This is causing the tray to come off the gear inside the microwave. I'm assuming it's a matter of time until this only gets worse.Solutions?What do I need to know about being safe when working on a microwave and does anyone have any advice on this motor problem? Does Westpoint even have a website or documents?ThanksJules