Question about Dewalt Small Angle Grinder 4 1/2"

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My dewalt dw 402 grinder, starts fine, runs for a few minutes and then shuts down. Brushes appear to be fine.

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Pull it apart and clean the armature, you will find something between the brush contacts getting larger and making contact thus shorting it out, so clean the armature with fine point object do not gouge the material out of the area between the copper plates. Also blow out any metal dust you may see.

Posted on Aug 06, 2009


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Maybe carbon brushes or motor.
Unscrew and pull back cover nearest cord.
Brushes should be touching rotor, the copper segments, and not too short. Smell for burnt offerings from the motor.
Some tools have thermal protection too.
See if there's a thermal fuse, which looks like a small shiny rod with a wire each end.
It could be inside sleeving.
On an electric motor, this is usually embedded in the stator, or field windings.**
This may have blown if grinder got too hot..
**Would need complete strip-down to inspect.
If motor is cooked, get wallet out.
Motor-parts/repair labor may cost more more than a new grinder.
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Take sample to store, with make/model of grinder.
Brushes fairly cheap.
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