PeachParts Mercedes-Benz Forum - View Single Post

rickg · #5 06-07-2003, 03:07 AM

Filing brushes will only help if the commutator that they contact is also in decent shape. Need to make sure each segment of the commutator is still seperate from it's neighbor segment, and that there isn't a deep groove worn around the diameter of the commutator from years of use. If there's no real wear, you can take something like an exacto knife and carefully scrape between each commutator segment to make sure the copper isn't mushed over, causing a short. Then take some fine grit sandpaper and clean them up until they look like copper again. Then use an air blast to clean off the grit and dirt.
The brushes may also be worn down so short that there isn't sufficient length to allow the springs behind them to make good contact between the brushes and the commutator. If the brushes are long enough, and the springs are in good shape, this stuff should make sure your getting a good electrical circuit. Can't tell you how long is long enough, but if they're worn down to little stubs, almost to where the wire is attached, they're probably shot.
The bearings, or bushings, whichever the motor has, of course need to be in good shape. Bad bearings will create too much friction when the motor is running, which will over heat the brushes and commutator, causing heat and arcing, which wears the brushes faster, and makes a mess of the commutator.
Inside the motor housing needs to be clean of dirt and crud. This will cause friction, heat build up, ect. You get the picture.
Next to doing all this, is getting another motor.