Just under the reed board is a wooden slip covered with soft leather, called the valve or pallet, which covers the openings in the reed board which admit air to pass down through the reeds. The tracker pin, pushed down by the key, opens the pallet which is held against the reed board by a spring and kept in place by a guide pin at each end. It sometimes happens that a pallet will be pushed down so far as to catch on the guide pins and cause the tone to sound continually. In other cases a piece of dirt will get in the way of the pallet and prevent it from closing the opening. If this be the case, draw the reeds that sound when this key is depressed and also a reed at each side of it, and pump the bellows briskly, at the same time pressing the three keys. This will generally create enough air to remove the obstacle. If the key still sounds and cannot be made to “hush up” in this way, you may be compelled to take out the entire action so that you can get to the pallets, which can be done by removing all the screws that hold the reed board in place. At the back, these screws are on top of the board and sometimes they are on top in front; but often they are under the air chamber in front. Be sure the screws are all out before trying to pull the board loose, as you might crack the board and thereby cause a leak. A moment’s notice will reveal the cause of the trouble in the pallet.
New pallet springs may be made of piano wire, using old springs for a pattern.
If a leak is found in the air boards, such as a crack or split, it can be stopped permanently by gluing a piece of bellows cloth or any good rubber cloth over the split. A leak in the bellows can be repaired in the same way, but if it happens to be a hole at or near a part of the cloth which is compelled to bend in the working of the bellows, you will have to use some kind of rubber or leather cement, preferably the latter. This can be made by dissolving gutta-percha in bisulphide of carbon, but a good leather cement may be had at almost any shoe store. If the bellows are porous, it may be well to give them a coat of cement, but never paint them; the paint cracks and the leaks are made worse.
Broken pedal straps are the most frequent annoyance. In all modern organs there is a panel above the pedals which will come out and admit the mechanic to the bellows, straps, springs, etc.; but in some old instruments the case is made solid, in which case the workman must do his work from the bottom, turning the organ down so as to get at it. Pedal straps are easily put on; generally with screws at either end. If the pedal squeaks examine the springs or oil and change their position slightly. Examine the pulleys over which the straps work and oil or rub them on the outside with soap. Broken pedal hinges may be duplicated by any blacksmith; the ordinary