<HTML>as you probably know, a gulbransen stack must be cut apart and then cork or similar gasket material added for the saw kerf....my suggestion would be to pull the stack and check for leakage making sure the pouches have been replaced and valves have been re-worked......if this is in order, you probably have to change the bottom bellows cloth and the leather valves which it sounds like was not done......isolate your components and determine where the problem is, if the job uptop is nice and neat, it probably, but not necessarily, is neat inside...your problem sounds like bellows...be sure to check the expression pneumatics as well as tempo and governor valves...if you want to , i have several players in various stages of reconstruction for sale...also i have a steinway-welte...(red welte) grand for sale...hope this helps tom mc nabb <A HREF="http://mcnabbmusic.com">Mc Music</A></HTML>