I havea 8 day sesions clock and it runs well for about 7 hours then stops.I notice it usually stops around the hour or near the half hour.Also it looks like maybe the mainspring on the time side, when it unwinds it may be touching the back plate.Wondering if this might be causing the clock to stop.

Troubleshooting things like this is a bit tricky without having it in hand, BUT..if it is stopping just before (you said around so I am not sure) the hour and the half hour, then it may be the strike train that is stopping things on the get ready.

Sometimes the lifting and locking levers have springs to keep them in place. If these springs are too strong, then too much pressure is put on the train and it can stop the clock.

A starting place anyway!?!

...again like Tom, not having the movement in hand it is often difficult to diagnose but from the symptoms you suggest I would guess that something is preventing the spring from exerting sufficient torque on the train after approx 7 hours...maybe the plates are 'cocked'...when the movement stops after the approx 7 hour run, try lifting the verge off the escape wheel to see if there is still 'hard' power in the timeside train...just some thoughts...

Thanks Tom and Jim, i will have a look and see what happens.

Update on this clock.After wondering what was causing the stoppage, i examied where it was sitting.It was sitting level on the length of the clock but on the width it was not.I had it sitting on the top portion of my closet, in the foyer.The drywall was near level near the edge but as you went further out it became quite unlevel.I moved the clock to my glass coffee table, wound it and it ran 2 weeks, wound it twice of course.It struck when it was supoosed to and did not slow down and stop.
I am happy it was not a more serious problem.

My brother in law really liked this clock so i sold it to him as i have one very similar to it.It is in it,s new home and is running well.

Great job Kevin!!