Hello, I've just purchased a older pendulum mantel clock. As it goes thru the 24 hour cycle as it arrives and strikes at 11 we get 23 as I see the (detent lever?) does not return to it's detent but, as the 11th strike it stays in the lifted position and continues to the 12 o'clock striking. why only at 11?
just happens at 11 because there is some minor irregularity in the gearing there.
often in count wheel striking systems (sounds like this one is)the cause is the shutoff lever nose does not drop straight down into the slot but instead hits on the side of the slot. A slight bend with a pair of pliers so it drops cleanly into the deep shut off slot is all that is needed.
the other wire arms attached to the same shaft can be out of adjustment but they cannot be accessed with out removing the movement and can get very tricky to adjust and I do not reccomend a non-pro try it- easy to make it worse.