How to Repair a Grandfather Clock. Repairing a grandfather clock is typically left to professional clock and watchmakers due to the intricacies of the mechanisms within the timepiece. Grandfather clocks more than 50 years old are considered antique and may have different rules for repair compared to their modern counterparts. A skilled watch and clock repair facility can diagnose most grandfather clock issues, yet there are some repairs an owner can undertake.
Check the weight of the grandfather clock. The time can be altered or incorrect if the weights are misaligned. Each weight has a marking on the bottom to indicate right or left weight. There may even be a weight marked center. Place each weight on the proper side for the clock to run smoothly or at all.
Free up the hands on the grandfather clock's face. If the pendulum is not swinging, the hands of the clock may have locked together. Gently open the face glass and move the hands away from one another. Ensure that the weights have been pulled up.
Move the pendulum bob up the pendulum shaft if the grandfather clock runs too slowly or reverse the process if it is running too quickly. Use a small screwdriver to free the bob.
Repair the moon dial if the sequence is incorrect. Determine exactly what phase the moon is currently in. Open the face glass of the grandfather clock, press lightly against the moon dial and rotate gently towards the current moon phase.
Level the grandfather clock. A grandfather clock that sits even slightly off level may eventually stop keeping the correct time. Ensure that the pendulum swings properly at the best level position.