The starting problem could be worn brushes. You should inspect them
and replace them if the show lots of wear. You can order brushes
from any one of the jewelry supply houses.
The noise problem could be due to several things. You might
disconnect the cable assembly from the motor. Then run the motor.
If you still have the noise with the cable removed then the noise
is coming from the motor. The noise could be the fault of the bad
bearings. Foredom could replace the bearings.
If there is no noise when the cable is removed then the problem is
in the cable. You can replace the entire cable assembly or
replaces pieces until the noise is gone.
To start with lube the existing shaft. If that does not end the
noise you need to install a new shaft in the sheath. Lube it well
before placing it in the sheath. If you still have noise after
installing a new shaft then you will need to install a new sheath.
All cable pieces, brushes and lube can be purchased from any one of
the jewelry supply houses.