There is a broken gear in the gear reduction box. (explain:) the motor spins at a high rpm, the chain moves at a 1/4 or less rpm than the motor. a series of gears reduces the speed, which in turn creates torque, allowing the saw to have the force to keep cutting without stopping. One of the gears is broken or a keyway on a shaft is sheared...as far as i know, no electrical power tools are rebuildable. it's a safety thing (electric shock if reassembled wrong...they are priced for replacement...get a new one...
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There is a broken gear in the gear reduction box. (explain:) the motor spins at a high rpm, the chain moves at a 1/4 or less rpm than the motor. a series of gears reduces the speed, which in turn creates torque, allowing the saw to have the force to keep cutting without stopping. One of the gears is broken or a keyway on a shaft is sheared...as far as i know, no electrical power tools are rebuildable. it's a safety thing (electric shock if reassembled wrong...they are priced for replacement...get a new one...