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Hobart A120 help

pjkobulnicky's picture
pjkobulnicky

Hobart A120 help

I have a reconditioned 12 Qt. Hobart A120. I bought it about 6 months ago. Just recently it stopped turning in first speed. The motor hums but I cannot get the shaft to turn. I have tried manually turning the dough hook back and forth while the motor is running (with proper caution to where my hands are so I can get them out of the way) to see if I can get the gears to engage but no luck. I have also tried tweeking the position of the speed lever with no success. . The mixer engages just fine on second and third speed.

Does anyone out there have any suggestions? Can you pass me along to a friend who might know? Can you point me to a schematic of the drive gearing?

pjkobulnicky's picture
pjkobulnicky

I found the parts schematic but still would like some diagnostic help.

wilg's picture
wilg

I wouldnt advise trying to turn the the planetary while the mixer is plugged. the only way to find out is to open the transmission case. Having bought this 6 months ago, would they any warranty? A lot of third party resellers will only do a "cosmetic" reconditioning or partial overhaul like planetary work, or changed the cord (for example), when you open the transmission case, youll notice that it will be filled up with grease/lube. Id expect a clean and consistent grease since it was reconditioned 6months ago. Then Id have to remove a majority in order to visualize the gears. When the grease is remove, you can test by switch the speeds and manually turning the planetary (*mixer unplugged). I suspect in your case that teeth on gear for the first speed have been fully worn or some metal bits is/are blocking the gear causing this to seize (rarely happens but some metal parts floating around).

You can order parts for a120 from partstown, official hobart and sometimes fleabay

 

pjkobulnicky's picture
pjkobulnicky

After looking at the schematic and noting the presence of keys in the drive train and after finding that the planetary turns free in both directions ( unplugged ) in low speed but not in the other two speeds it seems that a sheared key is the likely problem. Thoughts?

wilg's picture
wilg

Hello-Its possible that it could be one of the keys. There are 7 on the a120, I believe. If one of them is bent or stripped, this can cause the gears to disengaged. But youd still have to remove the transmission case and remove the grease to check for issues. Once you find out what the culprit is, its also a good idea to replace other parts that are close to its end life (while youre at it). Also,take good notes when you re-assemble them as they can be deceivingly similar and could also function but seize again after making a few batches of mix. Good luck