If the movement is worn to badly, it might be best to replace it. Of course the clock should be leveled first so the pendulum does not hit one side. It has to be adjusted so the beat is even like. As far as the clock not running more than 15 seconds, it could be that it is out of beat, meaning the tick tock is uneven, sounding like. Adding weight will possibly get it to run for a while, but that just adds to the wear problem and should not be done. The Jauch 77 has a history of excessive wear and the first problems usually arise in the chime train, either slowing down or failing. If a heavier pendulum such as a Lyre pendulum is swapped for the wooden stick pendulum, sometimes a heavier center weight is used to insure the reliable running. I have seen either configuration come from the factory. 5' X 5-1/4' square) movement are all either 4.4# or 4.7#. The factory specs on the Jauch 77 (approx. Jason, the position of the weights is that the strike weight is on the left (as you face the clock), the time is in the center and the chime is on the left.
