I just got done fixing a unit with this problem. After a bit of time, dirt will build up in the lower unit and clog the vacumm tube. Symptoms: No air flow coming out of the vacuum. Motor is hot. Stuff is spitting out of the front Motor wouldnt start it had over heated. You should remover the roller and clear the clog by hand. Let the motor cool down and it should start once it had cooled down.
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