For the second pouring, somewhat hotter compound may be used. Fill the cover channels flush with the top of the case, and again run a soft flame over the compound to make it flow freely and unite with the covers, and to give it a glossy finish. If any compound has run over on the covers or case, remove it with a hot putty knife.

Burning-on the Cell Connectors

With the covers in place, the next operation is to burn in the cell connectors. Directions for doing this are given on page 213. If you did not fill the jars with electrolyte before sealing the covers, do so now. See page 364.

Marking the Battery

You should have a set of stencil letters and mark every battery you rebuild or repair. Stamp "POS," "P," or "+" on positive terminal and "NEG," "N," or on negative terminal. Then stamp your initials, the date that you finished rebuilding the battery, and the date that battery left the factory, on the top of the connectors. Record the factory date, and type of battery in a book, also your date mark and what was done to the battery. By doing this, you will always be able to settle disputes that may arise, as you will know when you repaired the battery, and what was done.

To go one step farther, keep a record of condition of plates, and number of new plates, if you have used any. Grade the plates in three divisions, good, medium and doubtful. The "doubtful" division will grow smaller as you become experienced and learn by their appearance the ones to be discarded and not used in a rebuilt battery. There is no question that even the most experienced man will occasionally make a mistake in judgment, as there is no way of knowing what a battery has been subjected to during its life before it is brought to you.

Cleaning and Painting the Case

The next operation is to thoroughly clean the case; sc.r.a.pe off all compound that has been spilled on it, and also any grease or dirt. If any grease is on the case, wipe off with rag soaked in gasoline.

Unless the case is clean, the paint will not dry. Brush the sides and end with a wire brush; also brighten the name plate. Then coat the case with good asphaltum paint. Any good turpentine asphaltum is excellent for this purpose. If it is too thick, thin it with turpentine, but be sure to mix well before using, as it does not mix readily. Use a rather narrow brush, but of good quality. Paint all around the upper edge, first drawing the brush straight along the edges, just to the outer edges of rubber tops. Now paint the sides, ends and handles, but be careful not to cover the nameplate. To finish, put a second, and thick coat all around top edge to protect edge of case. Paint will soak in around the edge on top of an old case more easily than on the body of the case as it is more porous.

Charging the Rebuilt Battery

With the battery completely a.s.sembled, the next step is to charge it at about one-third of the starting or normal charge rate. For batteries having a capacity of 80 ampere hours or more, use a current of 5 amperes. Do not start the charge until at least 12 hours after filling with electrolyte. This allows the electrolyte to cool. Then add water to bring electrolyte up to correct level if necessary. The specific gravity will probably at first drop to 1.220-1.240, and will then begin to rise.

Continue the charge until the specific gravity and voltage do not rise during the last 5 hours of the charge. The cell voltage at the end of the charge should be 2.5 to 2.7, measured while the battery is still on charge. Make Cadmium tests on both positive and negatives. The positives should give a Cadmium reading of 2.4 or more. The negatives should give a reversed reading of 0.175. The tests should be made near the end of the charge, with the cell voltages at about 2.7. The Cadmium readings will tell the condition of the plates better than specific gravity readings. The Cadmium readings are especially valuable when new plates have been installed, to determine whether the new plates are, fully charged. When Cadmium readings indicate that the plates are fully charged, and specific gravity readings have not changed for five hours, the battery is fully charged. If you have put in new plates, charge for at least 96 hours.

Measure the temperature of the electrolyte occasionally, and if it should go above 110F., either cut down the charging current, or take the battery off charge long enough to allow the electrolyte to cool below 90F.

Adjusting the Electrolyte

If the specific gravity of the electrolyte is 1.280 to 1.300 at the end of the charge, the battery is ready for testing. If the specific gravity is below or above these figures, draw off as much electrolyte as you can with the hydrometer. If the specific gravity is below 1.280, add enough 1.400 specific gravity electrolyte with the hydrometer to bring the level up to the correct height (about 1/2 inch above tops of plates). If the specific gravity is above 1.300, add a-similar amount of distilled water instead of electrolyte. If the specific gravity is not more than 15 points (.015) too low or too high, adjust as directed above. If the variation is greater than this, pour out all the electrolyte and add fresh 1.280 specific gravity electrolyte.

After adjusting the electrolyte, continue the charge until the gravity of all cells is 1.280-1.300, and there is no further change in gravity for at least two hours. Then take the battery off charge and make a final measurement of the specific gravity. Measure the temperature at the same time, and if it varies more than 10 above or below 70, correct the hydrometer readings by adding one point (.001 sp. gr.) for each 3 degrees above 70, and subtracting one point (.001 sp. gr.) for each 3 degrees below 70. Be sure to wipe off any electrolyte which you spilled on the battery in adjusting the electrolyte or measuring the specific gravity. Use a rag dipped in ammonia, or baking soda solution.

High Rate Discharge

Whenever you have time to do so, make a 20-minute high rate discharge test on the rebuilt battery, as described on page 266. This test will show up any defect in the battery, such as a poorly burned joint, or a missing separator, and will show if battery is low in capacity. If the test gives satisfactory results, the battery is in good condition, and ready to be put into service, after being charged again to replace the energy used by the test.

CHAPTER 16.

SPECIAL INSTRUCTIONS.

EXIDE BATTERIES

Exide batteries may be cla.s.sified according to their cover constructions as follows:

1. Batteries with single f.l.a.n.g.e covers, as shown in Figs. 15 and 238.

This cla.s.s includes types DX, LX, LXR, LXRV, PHC, XC, XX, and XXV.

[Fig. 238 Exide Battery, partly disa.s.sembled]

2. Batteries with double f.l.a.n.g.e covers, as shown in Fig. 242. This cla.s.s includes types MHA, KZ, KXD, LXRE, and XE. The cover constructions are-described in Chapter 3.

All Exide batteries, except types KXD, LXRE, and XE, have burned-in lead top connectors. All types have a removable sealing nut around each post to make a tight joint between the post and cell cover, as described on page 19. Formerly some Exide batteries had cell connectors which were bolted to the cell posts, but this construction is now obsolete. Types KXD, LXRE, and XE have cell connectors made of flexible, lead coated copper strips.

Types DX, LX, LXR, LXRV, MHA, PHC, XC, XX, and XXV have been designed and built to meet the requirements of starting, lighting and ignition service for pa.s.senger automobiles and power boats.

Types KXD, LXRE, and XE have been especially developed to meet the requirements of the starting, lighting and ignition service on motor trucks and tractors.

Type KZ has been produced particularly for motorcycle lighting and ignition service.

[Fig. 239 Exide Battery with Single f.l.a.n.g.e Cover]

Type Numbers

The type of an Exide battery is stamped on the battery name plate.

Thus, on one of the most popular Exide batteries is marked Type 3-XC-13-1. Other Exide batteries have different numerals and letters in their type numbers, but the numerals., and letters are always arranged in the same order as given above. The first numeral gives the number of cells. The letters give the type of cell. The numerals following the letters give the number of plates per cell. The last numeral indicates the manner of arranging the cells in the battery case. Thus, in the example given above, 3-XC-13-1 indicates that there are three cells in the battery, that the type of cell is XC, that each cell has 13 plates, and that the cells are arranged according to method No. 1, this being a side to side a.s.sembly.

Methods of Holding Jars in Case

Two methods of holding Exide jars in the battery case are used:

1. Types MHA, KXD, LXRE, and XE have the jars separated by horizontal wooden s.p.a.cers, there being two s.p.a.cers between adjoining jars.

Running horizontally between these two s.p.a.cers are tie bolts which pa.s.s through the case. These bolts are tightened after the jars are placed in the case, thus pressing the sides of the case against the jars and holding them in, place.

Types KXD, LXRE, and XE, in addition to the tie bolts, are secured in the case by sealing compound beneath and around the jars. Each cell is provided with two soft rubber buffers which are V shaped, and are placed over the ridges in the bottom of the jars, thereby minimizing the effect of shocks on the plates and separators which rest on the buffers.

2. In types DX, LX, LXR, LXRV, PHC, XC, XX, and XXV, there are no s.p.a.cers between adjoining jars, and the jars simply fit tight in the case. Should they not fit tight enough to hold them in place securely, thin boards are inserted between the jars and the case to pack them in.

Type KZ has the three sets of plates in one jar, having three compartments, with a three compartment cover.

Opening Exide Batteries