Are you positive it's the motor and not a broken wire ?..... Check out this site  http://www.clayraku.fsnet.co.uk   Then click on ( DYSON DC04 )  This guy thought his motor was u/s then found it was a broken wire near the switch ( common fault ) The site shows you how to take the switch out to check the cable...There's also a part about the motor.
                 Eric
                
 September 2005