I have Anderson windows since 1985. The hand crank does work worm gear is worn out. I can't read on the windows model number or Serial number. Do you have any of vices.
Tom from SWISCO responded:
May 27, 2020
Hello! This looks like it would be either our 39-095 or 39-151, depending on the length of the arm. Look these products over to determine the best match.