Expert: Martin Meyer - 1/29/2008

Question
I just purchased a used Howard/Miller mantle clock. After
fully rewinding the three wind-up slots with the key, the
clock is running to fast.(about 20 minutes/hr)Is the a way
of adjusting the speed so that it will keep the proper time? Thank you in advance for your reply.

Answer
Hi Ed,
    A gain as great as 20 minutes per hour indicates a problem other than regulating. You don't indicate if this is a pendulum clock or not. If it has a pendulum, it may be connected improperly. Please refer to my Answered Questions for detailed information on the correct setup of the pendulum assembly.
    If your clock does not have a pendulum, it is a "floating balance" or balance wheel movement. Extreme gain in timekeeping can be caused by a number of things in these clocks: bent or dirty hairspring, incorrectly adjusted escapement, or bearing wear in the movement. These movements are quite difficult to adjust, and I would recommend taking the clock to a professional clock repairer.
    Finally, if the pendulum is barely swinging, or the balance wheel is barely rotating, the clock may either need lubrication or have excessive wear in the bearings of the gear train and need a new movement. These problems can cause a clock to run very fast. Again, diagnosis of these problems is a job for a professional clock repairer.