If your cuckoo clock has stopped chiming, or is not chiming correctly, this is most likely due to a lack of maintenance. Most clock manufacturers recommend oiling a clock every year. Though this is a very good practice, if done correctly a clock can generally go 2 to 3 years between oilings. After 1980, when whale oil used for clocks was banned, a petroleum oil was developed. This oil works very well, but unlike whale oil, petroleum oil evaporates. After 3 years, residue from the oil and trapped airborne dust is left behind. This trapped debris will wear the clock's pivots and its bearing surfaces. Thus, the clock often stops working because of lack of lubrication or from the worn parts. Below is a guide to rebushing worn pivot holes in your clock.