1980's kenmore 110 -70 series -82372110 .timer switch somtimes stops machine at last part ospin cycle to spin off last bit of water.when it does .itap on lid and it finnishes cycle. this for last 3 years .ok with me.did wash today when it got to this part of cycle drum stopped spinning and made a loud grinding -buzzing noise.tapped on lid it would not finnish cycle..pulled away from waal pushed on drive belt. took out clothes.set timer knob to last part of spin cycle and it worked as usual . put clothes back in set to last part of spin cycle and it worked as usual..questions ? what was that buzzing noise ? was it the timer control or the drive belt is loose?