Part 52 (1/2)

Remove all sealing compound from the jar by means of a hot putty knife, finis.h.i.+ng by wiping with a gasoline soaked rag. Inspect each jar carefully under a strong light for cracks and leaks. If you know which jar is leaky by having filled each cell with water up to the correct level, when you made the first examination of the battery, and then having it allowed to stand over night to see if the electrolyte in any cell has dropped below the tops of the plates, no tests are necessary, but if you are in doubt as to which jar, if any, is leaky, you must make tests to determine which jar is leaky. If you know that there is no leaky jar, because of the bottom of the case not being acid eaten and rotted, it is, of course, not necessary to test the jars.

One test consists in filling the jar within about an inch of the top with old or weak electrolyte, partly immersing the jar in a tank which also contains electrolyte, and applying a voltage of 110 or 220 between the electrolyte in the jar and the electrolyte in the tank in which the jar is partly immersed. If current Vows, this indicates that the jar is leaky.

[Fig. 220 Testing jar for leaks, using a 15-watt lamp in series with test circuit]

Fig. 220 shows the principle of the test. A suitable box,--an old battery case will do--is lined with sheet lead, and the lead lining is connected to either side of the 110 or 220 volt line. The box is then partly filled with weak electrolyte. The jar to be tested is filled to within about one inch of the top with weak electrolyte. The jar is immersed to within about an inch of its top in the box. The top part of the jar must be perfectly dry when the test is made, or else the current will go through any electrolyte which may be wetting the walls of the jar. A lead strip or rod, which is connected to the other side of the 110 or 220 volt line, through a lamp as shown, is inserted in the jar. If there is, a leak in the jar, the lamp will burn, and the jar must be discarded. If the lamp does not light, the jar does not leak.

Instead of using a lead lined box, a stone or earthenware jar may be used. A sheet of lead should be placed in this jar, being bent into a circular shape to fit the inside of the jar, and connected to one side of the line. The lead rod or sheet which is inserted in the jar may be mounted on a handle for convenience in making the test. The details of the testing outfit may, of course, be varied according to what material is available for use. The lamps should be suitably mounted on the wall above the tester.

[Fig. 221 Testing jar for leaks, using a voltmeter in series with test circuit]

This test may be made by using a voltmeter instead of lamps, as shown in Fig. 221. If a voltmeter is used, be especially careful to have the part projecting above the liquid perfectly dry. A leaky cell will be indicated by a reading on the meter equal to the line voltage.

[Fig. 222 Testing jar for leaks, using secondary of Ford ignition coil, or any other vibrator ignition coil]

A third method uses a Ford ignition coil, as shown in Fig. 222. A leak will be indicated by a spark, or by the vibrator making more noise than it ordinarily does. Instead of using the Ford coil, as shown in Fig. 222, the test may be made as shown in Fig. 223. Fill the jar to within an inch of the top with electrolyte and immerse one of the high tension wires in the electrolyte. Attach the other high tension wire to a wire brush, comb, or rod having a wooden handle and rub it over the outside of the jar. A leak is shown by a spark jumping to the jar.

[Fig. 223 Testing jar for leaks, using secondary of Ford ignition coil, or any other vibrator ignition coil]

The test may also be made without removing the jar. If the lead lined box be made two feet long, the entire battery may be set in the box so that the electrolyte in the box comes within an inch of the top of the battery case. Fill each jar with weak electrolyte and make the test as before. If this is done, however, remove the battery immediately after making the test and wipe the case dry with a cloth. To make the test in this way, the case must be considerably acid eaten in order to have a circuit through it to the jar.

Removing Defective Jars

The method of removing the jars from the case depends on the battery.

In some batteries the jars are set in sealing compound. To remove a jar from such a battery, put the steam hose from your steamer outfit into the jar, cover up the top of the jar with rags, and steam the jar for about five minutes. Another way is to fill the jar with boiling hot water and let it stand for fully five minutes. Either of these methods will soften the sealing compound around the jar so that the jar may be pulled out. To remove the jar, grasp two sides of the jar with two pairs of long, flat nosed pliers and pull straight up with an even, steady pull. Have the new jar at hand and push it into the place of the old one as soon as the latter is removed. The new jar should first be steamed to soften it somewhat. Press down steadily on the new jar until its top is flush with the tops of the other jars.

Some batteries do not use sealing compound around the jars, but simply use thin wooden wedges to hold the jars in place, or have bolts running through opposite faces of the case by means of which the sides are pressed against the jars to hold them in place. The jars of such batteries may be removed without heating, by removing the wedges or loosening the bolts, as the case may be, and lifting out the jars with pliers, as before. New jars should be steamed for several minutes before being put in the case. When you put jars into such batteries, do not apply too much pressure to them, as they may be cracked by the pressure, or the jar may be squeezed out of shape, and the a.s.sembling process made difficult.

[Fig. 224 Was.h.i.+ng sediment from Jars. Water supply controlled by foot valve]

Repairing the Case

The case may be repaired with all the jars in place, or it may be necessary to remove the jars. If the case is to be junked and the jars used again, the case may simply be broken off, especially if there is much sealing compound around the jars.

Empty the old acid from the jars, take the case to the sink and wash out all the sediment, Fig. 224. With the pipe shown in Fig. '14, you have both hands free to hold the case, as the water is controlled by'

a foot operated spring c.o.c.k.

If the case is rotten at top, patch it with good wood. If the top and bottom are so rotten that considerable time will be required to repair it, advise the owner to buy a new case. Sometimes the top of the case can be greatly improved by straightening the side edges with a small smoothing plane, and sometimes a 1/2 inch strip or more fitted all along the edge is necessary for a good job. Handles that have been pulled, rotted, or corroded off make disagreeable repair jobs, but a satisfactory job can be done unless the end of the case has been pulled off or rotted. Sometimes the handle will hold in place until the battery is worn out by old age if three or four extra holes are bored and countersunk in the handle where the wood is solid, and common wood screws, size 12, 1/2 or 5/8 inch long used to fasten the handle in place. Sometimes it will be necessary to put in one half of a new end, the handle being fastened to the new piece with bra.s.s bolts and nuts before it is put into place. Sometimes you can do a good job by using a plate of sheet iron 1-16 inch thick, and 4 inches wide, and as long as the end of the case is wide. Rivet the handle to this plate with stovepipe, or copper rivets, and then fasten the plate to the case with No. 12 wood screws, 1/2 inch long.

If the old case is good enough to use again, soak it for several hours in a solution of baking soda in water to neutralize any acid which may have been spilled on it, or which may be spilled on it later. After soaking the case, rinse it in water, and allow it to dry thoroughly.

Then paint the case carefully with asphaltum paint.

REa.s.sEMBLING THE BATTERY

Rea.s.sembling the Elements