The center hole is for the time train, the right hole is for the chime train and the left hole is for the hour strike. Just wind them up until they stop. Over winding is a myth. If the clock does not run it is either dry, dirty or worn out. A mechanical clock can be repaired at most "good" clock repair shops. If your clock is an 8 day, you wind it every 7. This way the clock does not stop between winding.
Stevens Clocks
June 2010
all of the three. put the key wind in one of those holes and turn counter-clockwise. DO NOT WIND IT UP IF IT IS CHIMING OR STRIKING. it will destroy the clock. dont overwind it. stop if it is fully wound. you will know that it is fully wound that it will stop. dont force it when it stops. it will overwind. if done from a hole do it again on a different hole until it is fully wound. after 8 days after fully wound wind it up again.
David
May 2010
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