While cutting concrete with a masonry blade, I heated the saw up to a point where it started to spark at the motor and then stopped running. After letting it cool down for a few hours I tried the machine again. It "works". However, although the circular saw runs, it continues to spark profusely at the rear of the motor.Before I change a bunch of parts I was hoping someone could pinpoint the problem for me. Thanks, Eric

Eric, July 2009

There is a good chance you could have burned up the motor, but try checking your brushes to see if they have collapsed or if they still have tension. If the spring has collapsed you can start by replacing the brushes, part # 145323-02.
http://www.toolsandmachinery.com/product_info.php?products_id=11625

Don- www.toolsandmachinery.com, July 2009

You can expect a degree of sparking where the carbon brushes contact the commutator...however, if you have over loaded your saw to an extent you would probably find some pitting on the copper segments of the commutator. Personally I'd just live with it and see how things go, but you could remove the brushes and see how long they are.

John, July 2009