The switch itself was taken apart and several of the contact points were badly arced . I was able to use a fine file and clean them up. The switch spring which slides on the motor shaft was also cleaned , lubed, and all dirt blown out of the area. So far the motor now comes up to speed with very little hesitation. not perfect but much better. Further work is in process to use a newer blower wheel on the shaft . A blower wheel to fit the motor threaded stem is not available so I am reworking the threaded stem to accept an old design "D" ring mount type of wheel to direct air flow into the ducting . Hopefully it will work and stay in place with a retaining nut.