is the motor running but the blade fails to turn if so it's the drive belt. if the motor is just humming it may serious unplug the saw and check that the blade is free to turn. if the blade is free then it is probably the motor. i would take a look at the brushes if the fault is more intermittant. the brushes are available fron solent tools ltd tel 023 8057 8057
martin
March 2008