I have a 20 quart mixer and its making some grinding noise

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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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.

One or more of the gears in the gear housing is stripped. Here is the parts list for the machine. Take it apart and find the stripped gear and replace it.


http://shared.whirlpoolcorp.com/assets/pdfs/literature/Repair%20Part%20List%20-%208212369.pdf

I needed to replace the nylon worm drive in my mixer. When I put it back together, I found that my mixer made a kind of grinding noise. The noise was due to a vibration associated with the cover for the electrical wiring in the back of the mixer. I solved my noise simply by loosening the screw to this cover. The cover is located on the back of the mixer, and the screw is on the top.
Separately, to find instructions for opening your mixer, you can go to http://neilcrockett.com/mixer.htm.

They seem to have a plastic gear built in as protection for overloading (prob). When the machine counters to much resistance that gear will strip its teeth causing the machine to not be able to turn, that it what seems to be the grinding problem. If it is not the plastic gear then it another gear that is "stripped(of its "teeth") I hope your problem is not a severe, but if your mixer is "locked up" then at least you found the problem.

A 200 means 20 quart. I assume you have no bowl or else you can just measure the volume of the bowl.

Hi. Your problem probably lies in the plastic transmission housing. This cheap piece of plastic has no business in a high priced mixer, as it has two important shafts that depend on the integrity of this housing for their bearing seats

Remove the top cover from the mixer. At the front top of the mixer is the trans. housing. Examine this housing carefully for cracks. If you find cracks, then you have new damage inside the mixer. If, when you replaced the three gears, I suspect that you did not discover the cracks in the trans. housing and reinstalled it after you replaced the gears, or you may have missed internal damage from the first breakdown.

When this cheap plastic part fails, it can destroy the worm gear, it's bearings and the bearing seats and possibly more.

Kitchenaid's replacement housing is made of metal. Kitchenaid markets these mixers saying it can handle bread dough. The ugly truth is they cannot!

You must open the unit up, remove and save the grease if it's relatively new. You must check every moving part in the mixer's transmission. You have to remove grease from these parts in order to find the damage. When you have the unit repaired, sell it!

I had the same problem with my mixer. I replaced all of the broken parts, and sold it. Since then, I bought a used Hobart N50 ( 5 quart), and an A200 (20 quart) mixers, both of which are commercial mixers. Both of these can handle heavy dough and they do so with ease.

Kitchenaid, to this date, have refused to recall these trans. housings, even though thousands of these cheap plastic housings have failed. Good luck with this saga!

If this solution has assisted you, please rate it. ricardok45

Hi im a service tech for hobart.I cant give service manuals out because i could lose my job but i can step you thru your problem with the mixer,let me know.

If it's metallic sound you are loosing teeth on a gear or two.  This is caused by lack of lubricant or simply fatigue of the material of the gears.  Don't use it, you can get metal flakes in your food.

Take it in to a repair shop and have it fixed.  The money spent is well worth it because if done correctly will last another 12 years.

common problem. Worm gear & bracket #PS734273 about $36.