it is raised higher and the suction below it lifts the deck-leather valve, and water in the pipe rises for the next stroke. In this way a more or less continuous stream of water is lifted from the depths and flows from the top of the cylinder through the open spout or "pitcher" lip. Varied forms of the pitcher pump exist, but the essentials of operation are identical.
The force pump makes use of the same principle, but the cylinder is entirely closed and the lifted water is directed into a closed chamber called the air dome. In there it comes into contact with a body of air which after compression by the in-flowing water, forces the water in a continuous and steady stream to a considerable distance or height. The compressed air forms a wonderfully powerful cushion and in this manner creates an internal pressure very useful in filling overhead tanks or projecting the pumped water along a rising pipe line.
Deep-well pumps are essentially the same as the simple shallow-well pumps except the pumping cylinder may be separated many feet from the pump body. This is because the plunger can only operate at a maximum of about 28 ft. above water level. Therefore, for a 50-ft. well, the cylinder must be placed in a pit or driven to within at least 28 ft. of the water level, and the plunger operated from above ground by a long rod running down through the pipe to the plunger rod in the cylinder.
The leathering of any of these types of pumps is essentially the same. Where the entire pump is above ground, the job is simple. If one or more cylinders are below ground the job becomes more difficult. But the leathering job remains the same; the plunger and the deck leather must be renewed.
The first thing to do with a shallow-well pump is to trip the water out by forcing the plunger down until you hear a sucking noise and the water drops back into the well. Then loosen the bolts holding the cylinder and the base casting together and lift the cylinder off. This exposes the deck leather, shown clearly in the photograph illustrating this operation. The drawing on page 165 also shows the shape of a typical deck leather and its component parts. It consists of a circular ring of stiff leather inside of which is a round leather disk attached to the ring at one side. The open space between is horseshoe-shaped and permits the passage of water. A weight fastened to the disk helps to force it in place over the deck opening and thus make it a quicker-operating and tighter-fitting valve.
Remove this leather carefully so as not to score the metal deck or seat. If it is hard or cracked it should be discarded and a new leather provided. Remove the clapper weight by taking out the retaining screw in the center. Fit this on the new leather in its proper position, which is with the raised lug over the hinge. If no ready-cut leather can be obtained, a suitable one can be cut from a piece of 1⁄8-in. oak-tanned stock by placing the old one over it as a pattern and marking around it with a pencil. Then cut the new one out with a sharp knife and fit the clapper weight to it. If the old leather is beyond use as a pattern, place the new piece of leather over the deck and tap it gently but firmly with the ball end of a ball-peen hammer around the outside edge and the edge of the pipe opening. When removed. the markings of the metal edges will be plainly visible and can be followed with the cutting knife.
Before the new deck leather is placed in position, wipe the deck clean of any dirt or grit. If any slight bits of nicked metal exist along the surface, smooth them off with a fine emery stone. Soak the new leather in water an hour or two to thoroughly soften it and then lay it carefully on the deck. still wet, placing the weight uppermost. When in the proper position, place the cylinder carefully upon it so as not to disturb its position, reinsert the bolts and take up on them slowly and evenly until the leather is firmly clamped in position. Use care in taking up on these bolts, taking a part of a turn on each one at a time. This will compress the leather evenly and also prevent clamping down one side before the other, and thus insure even pressure and eliminate chances of cracking the casting from uneven pressure on either side.
On deep-well pumps the cylinder must, of course, be removed from the pipe line before the packing can be accomplished. If it is in a pit, it is only a matter of removing the pipe from above and the
