Motor speed is erratic. Now it makes grinding noises

That is a $10k to $20k mixer, depending on where you buy it. I have used one of these. Unfortunately, grinding noises that result in the motor stopping can be fixed with a power disconnect.

Grinding noises = dry bearings, to seized bearings, to shredded or stripped gears. You need a Hobart Service Tech.

https://www.google.com/search?q=Hobart+Legacy+HL200

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The blades will need to be removed and cleaned. Make sure. Always make sure to Unplug your mixer before taking apart

If it is leaking you are going to have to go inside the gearbox to change the grease so whatever is wrong inside may become obvious when you take it apart. Remove accessory cap from the front and look for any dryish grindings inside there.

Check that the nuts under the back cover at the sides have a bit of nip on them. It could be the armature polling on the fields. DO NOT OVER TIGHTEN THOSE NUTS.

Tll,
It sounds like it could be an issue with the gear, the motor housing could have a crack in it. The problem could be much more involved as well. Put the unit on the slowest speed and see if you can stop the mixer from spinning. If it hiccups or stutters, that means you have a stripped gear. If you cannot stop the unit using your hand ON THE SLOWEST speed then there could be a problem with the motor housing or the motor itself not being held in place properly.

Hi,motor bearing usually worn out if you dont put grease on it.try also to check screws it might loosen up.Bearing might as well not contacted with the upper surface does it makes noise.Screw and bolts might as well loosen .Hope this helps.

It sounds like the Worm Gear is going out. The faster the motor runs,
the more damages the Center Gear is grinding away the teeth of the
Worm Gear. Things start to slow down, and eventually they will come
to a halt. It's time to replace the Worm Gear. Also make sure to use
new fresh Kitchenaid Food Grade Grease with the new replacement.

The green light is probably sparks. Does the light eminate from the rear? If so, it sounds like there is an issue with the control plate. Taking the rear off should hopefully help you spot what is wrong with it. I suspect the board has broken or got stuck.

Yes this indeed does sound like you have a problem. There could be a couple different cause of this noise. If your main drive or worm gear has been damaged, it is likely to not run at all or jam up. So i think this is not the problem. There is however a codder pin located inside the transmission gears this can be seen by removing the upper housing of the unit, and then exposing the oil and gears. clear away the oil surrounding the gears, and save this grease for later. After this you should be able to visually see this codder pin AND the gears, rotate the gears while inspecting them and the pin. If the pin is slightly bent or broken this will make the grinding noise that your are talking about, while still operating and driving the unit. part number for the codder pin is 9705444. If however the noise is coming from the motor area this could indicate a worn or faulty motor bearing. This can cause the motor to operate on an angle and can cause a rubbing noise from the cooling fan or the winding of the motor itself rubbing on the mixer housing. Part number for the braket and bearing is 3180526. both are relatively cheap and easy to replace. If you find and fix the problem be sure to inspect or change the oil as this can often have metal chunks and other particles. Hope this Helps

Thanks

The repair manual says that the mixer can make this grinding sound at slow speed, like stir or 2. This is normal, especially until it warms up. This is the sound of the gears turning at slow speed.