Remove the lens cells. Put the shutter in a jar slightly larger in diameter than the shutter. Pour in enough alcohol to just cover the shutter. Soak for 30 minutes to 1 hour. Remove and operate at 1 second to 1/100 second. Return to the alcohol for an additional 30 minutes to 1 hour. Remove from the alcohol, drain thoroughly and allow to dry over night. Test again.
OR
send it to me for a CLA.