Welding on an electric motor

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I have an electric motor that is the starter for a snowblower, one of the mounting ears broke off of the outside case of the motor.  My question, will MIG welding damage the armature in the motor if I weld to the case?  Can I leave it together, or should I disassemble the motor to where I have the case by itself before I weld on it?
Reply:If is series wound I don't think I would expect a problem. if it happened to be a permanent magnet motor. the magnets (in the case; used for field) could well be a problem. Permanent magnet motors are usually smaller and less common so you are probably in luck.-- fredLincoln 180C MIG
Reply:I'm sure you know this, but it doesn't hurt to repeat it...Anytime you're welding on an assembly with ball-bearings...place the ground clamp on the workpiece so the welding current does not run through the bearings.  So for welding a mounting foot on a motor, don't put the ground clamp on the shaft.
Reply:Also,Is the case cast iron... which would need more than just a quick squirt of wire? Is it  aluminum and needing to be cleaned well and to have cracks opened up?Is it steel and can you protect the windings with a wet cloth placed over them?Just wondering "out loud".
Reply:You should always place the work clamp as close to where you are welding as possible. The keeps welding current from going through things like bearings or instrumentation ( electronics). Old Iron brought out a good point. The windings should be insulated from the case but if it were to get very hot it might damage the insulation. A wet rag wrapped around the area you are welding in could help keep the heat down. Weld a little and then let it cool off will also help.
Reply:Yup, thanks for the tips.  I'm a noob welder (took a class), but seems like common sense to place the clamp as close as possible to the arc.  The case is just stamped steel with a steel plate tack welded on the outside with 4 mounting holes drilled in it.  Remember, this is a snowblower starter, it's not that big.  I know the current travels from the arc to the ground, so if I ground to the other piece of the mounting plate, the current won';t go through the motor at all....was more wondering if there was ancillary effect on the windings from being close to the current but doesn't sound like it.  Nice to have a place here to ask, instead of "I guess I should have taken this apart first...."  Thanks guys/