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Electric Motors/bosch battery impact motor


I have a bosch battery powered impact that quit operating so I took it apart. I found that the armature turns but the armature shaft slips in the armature under load. I have never seen the shaft and armature do this. I was wondering if there will be a way to repair or will I have to replace the motor.


So are you saying the armature turns but the shaft running through the armature iron stack and windings  slips,  like the shaft is loose or broken internally in the armature?

If that is the case,   it is a huge job to replace an armature shaft,   involves rewinding the armature,  removing the commutator,    big job,     

If it is slipping,   best bet is an armature,   a new one,   if all else is OK  you seem to understand motors,   so that is a huge help,   

Now the price of the new armature might be 75% of a new motor and in that case,   I would just do the motor,    but  I need to know If I am understanding exactly the problem      

Shafts will come loose inside an armature,    the laminations are sweat fitted on the shaft and once that fit is loose it is pretty much done for,    

But I want to make sure I am understanding if that is what is happening,   

Yes there is a way to fix it if that is the case, but cost     no way    the entire motor would be less I am guessing,   if you find the motor to be very expensive let me know   maybe there is a way around it,   

Another option  is to find a working impact on EBAY and rob the armature from it,    just a matter of the best cost.

Let me know  and if I have it correct,  and you can get an armature or motor,  reasonably priced  I would do that,          

Let me know if you have more questions if you get into this and something doesn't add up,

you can use my shops email anytime     or repair phone  816-650-4030     MEAR Services Inc,  Buckner Missouri  64016  

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Three phase/ AC DC single phase motors, controls, any problems or failures, motor installation, performance issues, connections. All other electric motors/gearboxes/apparatus. Specialty repair concerns, obsolete motors and solutions. Other mechanical or specialty equipment. See my profile under Home/electrical at this site


30 plus years in the electrical motor and apparatus repair industry. VP level management of repair facilities, current owner of my own specialty repair and consulting firm.

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