My friends dyson smokes?

My friends hoover starts to smoke as soon as she switches it on, when i had a quick look at it i found that she had been using it with no bottom filter so i stripped it down and cleaned the motor with a small paint brush only to find what appears to be a break in the copper coil though i can only find one end, is this why it was smoking or would that likley to be all the built up dirt, and if it is the cause can i do any thing to repair the coil other than buying a new one...
I have stripped down the motors of a few dysons and other household goods over the years and found that with some common-sense i could fix all but two of them.
Please only reply lf you now for sure,
Thanx.