Longcase Clocks - Common Faults

The clock appears to be over-wound.

This is term that is often used to describe a clock that has stopped and yet appears fully wound. It is exceptionally difficult to over-wind a clock and very rarely happens. It is more likely that the clock has seized up and requires a service or overhaul. If this has happened, please take it to a professional clock repairer.

The clock stops after only a few minutes (or does not run at all).

If this happens it may be because the clock is what we refer to as being ‘out of beat’ i.e the mechanism has not been leveled correctly. We often find that this happens when customers move a clock to a new location, and the clock is then sitting at a different level. You can tell if this is the case by listening to the sound of the tick. The tick tock should be even (the time between the tick and tock should be the same and not demonstrate a skipping sound). If it is not even then for a longcase build up one side of the case to see if that corrects the sound of the beat. If not transfer the packing to the other side and see if that corrects the beat.

Other causes of this fault could be that the pendulum is rubbing on the back of the case or one of the hands is rubbing on the glass door.

The clock will only run for 4 or 5 days (Thursday disease)

This problem often occurs if the clock case is not secured or wedged so that the case cannot move. When the weights reach the same level as the pendulum bob, they sometimes swing causing the clock case to sway (often unnoticeably to the eye) and will ultimately cause the clock to stop. Another reason could be that the weights are catching on the case at the bottom of the trunk door.

The clock stops 5-10 mins after or before the hour.

One possible cause of this is that the strike weight has wound down before the time weight has wound down causing the strike to jam which can stop the clock. First wind up the strike weight a little and then slowly move the hour hand round to the hour position and allow the clock to strike the hours. (If the hands lock while you are doing this stop and speak to a specialist clock repairer). Once the clock has struck the hours wind up the time weight and start the pendulum. Hopefully this will have rectified the problem. If not it may be that the strike train of the mechanism has a fault which would require you to take it to a clock repairer.

If the clock stops just before the hour, this may also be caused by the strike mechanism jamming. In this case try to take the minute hand back a full 20 minutes and then slowly move the hand forward. (Again, if the hands lock while you are doing this stop and speak to a specialist clock repairer). If this problem continues to develop, take your clock to a specialist clock repairer.

The clock does not keep the correct time – runs fast or slow.

To alter the timekeeping of the clock the pendulum bob needs to be adjusted. This is done by turning the screw/bolt which is located below the pendulum bob. If the clock runs slow turn the bolt to the right. This pushes the bob up the pendulum rod and increases the speed of the clock. If the clock runs fast, turn the bolt to the left. It is advisable to make one small adjustment and then leave it 24 hours before making another adjustment.