Just to let you know I've seen your question but am busy for the next could of hours. Will respond to you when I can
The fact that the clock ticks away rapidly without the pendulum suggests that sufficient power is getting to the pendulum for it to run OK. If this were not the case I'd suspect it needed cleaning oiling or servicing.
So the first thing to check is that it is 'in beat'. The pendulum should tick with an even beat - like a metronome - tick .. tock .. tick .. tock.. If it's not doing this, it will stop.
The easiest way to adjust this in the first instance is simply to tip the clock on the wall. It doesn't matter if the case is not vertical, as long as the sound is even. If it will run ok with the case at an angle we can sort that out after.
Can you let me know if this works. If not we need to try some other things.
Ha! I think I'll have to blame this one on the husband. He must have taken the shelf down to paint and put it back up crooked. I was heart sick that my clock might be broken. It works on a different surface!!!! Thanks so much. If I have anymore questions I'll try to direct them to you, but for now my questions have been answered. This is an awesome sight and you were a great help. I know you probably think it was a simple thing, but it's huge to me to have the clock not broken and working.
Sorry I didn't realise it was a mantle clock, but obviously the same applies as you've worked out. You said you took it down to paint the wall and that threw me!
Either way if it's ticking evenly it should hopefully be fine now.
All the best, Chris.