negative group should be washed and also laid aside until needed. The negative group should be immersed in water, otherwise it takes up oxygen from the air, which is liable to cause dangerous heating.

To remove a leaky jar, pour boiling water in the jar to soften the surrounding compound and lift the jar from the case. If the compound cannot be softened with boiling water, use a jet of steam or a flame on the inside of the jar. To install a new jar, pour boiling water in the jar. When it is thoroughly heated, press it carefully into place.

To Replace an Element: To assemble the new element: inter

Set Screw Type Wing Nut Terminal Box Type Terminal complete

Terminal

for Wire

with Lug

Fig. 30.-Terminal Types Used in Connection With Exide Vehicle

Batteries.

mesh the positive and negative group, positive and negative plates alternating. As a negative group contains one more plate than does the positive, both outside plates will be negative. Lay the element on its side, and put the separator retainers in position. Insert the separators between each pair of plates. If wooden separators only are used, the grooved side of the separator should be next the positive plate. If wood separators and rubber sheets are used, they should be inserted together, the rubber sheet between the positive plate and the grooved side of the wood separator. See that the separators are against the retainers and that they extend equally on either side of the element.

Grasping the element by the pillar posts, lower gently into the

jar. Fill with electrolyte of the proper density (see "Electrolyte") and let the cell cool for at least twelve hours. Develop the plates. It is advisable to develop with the cover off on account of better ventilation and greater convenience in taking thermometer and hydrometer readings. Furthermore, if a fault develops it can be remedied without having to remove the cover. Proceed as follows: Burn a copper wire (about No. 10) to the top of each terminal post with a few drops of burning material, just enough to make good connection. Connect these wires to the charging source. Develop at a rate equal to six-tenths (.6), the final rate of the battery. The time required to develop at this rate will be about sixty hours. After the developing has gone on for thirty hours, disconnect the charging wires and reconnect so as to charge the balance of the cells in the battery as well as the cell or cells being developed. When the cell voltage and the specific gravity have remained unchanged for five hours, the cell is fully developed. Even up the electrolyte in the cells to 1.300.

Place the upper and lower covers in boiling water. When the lower cover has become thoroughly heated, press it gently into position. Carefully clean the inside edges of the jar and cover with warm water and dry with a flame. Otherwise, the compound will not stick. If there are any openings between cover and jar wide enough to allow the heated compound to run into the jar, work a small amount of compound around these edges, using a putty knife or brush before starting to pour. Pour melted sealing compound around the edge. Allow a few moments for this compound to harden slightly, then pour melted compound until it reaches a point slightly above the top of the expansion chamber, and at once press the heated top cover on the compound. Place a weight on the top cover and let it remain until the top cover cools fast to the compound. Pour melted compound around the edges and to the level of the top of the cover and smooth off with heated putty knife. Burn the connecting links and terminals to the pillar posts.

Repairing Willard Automobile Type Batteries. In repairing a Willard storage battery a definite routine must be followed in tearing down and building up same in order that it will be in

the best condition when reassembled. These steps are as follows: First: Remove all vent plugs and washers.

Second: Center punch both top connectors in each cell which is to be repaired; then drill 34 inch into top connector with a

Fig. 31.-Diagram Showing Construction of Points to be Reached in Rebuilding or Tearing Down Willard Storage Battery.

5-inch diameter drill. Now pull off top connector with pair of pliers.

Third: Apply gas flame or blow-torch flame to the top of the battery long enough to soften the sealing compound under the top cover. Now, with heated putty knife, plow out the sealing compound around the edge of the top cover.

Fourth Insert a putty knife, or any other thin, broad-pointed tool, heated in flame, along underside of top cover, separating it

from the sealing compound. Then, with putty knife, pry the top cover up the sides and off of the terminal posts.

Fifth: Then, with heated putty knife, remove all sealing compound from inner cover.

Sixth: Now play the flame onto the inner cover until it becomes soft and pliable; then take hold of both terminal posts of one cell and remove the elements from the jar slowly; then lift the inner cover from the terminal posts.

Seventh: Now separate positive and negative elements, by pulling them apart sideways. Destroy old separators.

Eighth: To remove a leaky jar, first empty the electrolyte from the jar, and then play the flame on the inside of the jar until the compound surrounding it is soft and plastic; then, with the aid of two pairs of pliers, remove it from the crate, slowly, lifting evenly.

Ninth To put in a new jar, in place of the leaky one, heat it thoroughly in a pail of hot water and force it gently.

Tenth: In reassembling the battery, first assemble the positive and negative elements, pushing them together sideways, then turn them on the side, and with both hold-downs in place, insert new separators, being very careful to have the grooved side of the separators next to each side of the positive plate. Also be careful to have the separators extend beyond the plates on each side, so there will be no chance of the plates short circuiting. Now press all separartors up against hold-downs.

Eleventh Heat up inner cover with the flame; then place same on terminal posts; then take hold of both terminal posts and slowly lower the elements into the jar.

Twelfth Now, with expansion chamber in place on the inner cover, until it reaches the level of the hole in the top of the expansion chamber, i. e., so that when the top cover is replaced it will squeeze the sealing compound off the top of the expansion chambers.

Thirteenth: Now soften top cover with flame and replace on terminal posts until it rests on top of expansion chamber; then place a weight on top cover until sealing compound cools.

Fourteenth: Now pour sealing compound around the edge of

the top cover until it reaches the top of top cover; then, when the sealing compound has cooled, take a putty knife and scoop extra sealing compound off of top cover, making a smooth surface over all the top of the battery.

Fifteenth: In burning the top connector to terminal post, proceed as follows: Scrape the hole of the top connector until the surface is bright and clean; scrape terminal post until top and edge of all surfaces are free of dirt. Now, scrape a piece of lead thoroughly, preferably a small bar; then apply hydrogen-gas flame, mixed with air under pressure, to the top connector and terminal post assembled, at the same time heating lead bar. When top connector and terminal post begin to melt, apply lead bar directly on same, melting it, thus making a firm burned connection. Then fill rest of hole-space with melted lead and smooth off even with top of top connector.

General Care of All Lead Batteries: The battery boxes must be kept clean and dry. The acid-proof paint of both the boxes and the tanks must be kept in good condition by repainting when nécessary. The terminals must be kept thoroughly clean and covered by a coating of vaseline. Corroded copper, iron or any other foreign materials must not be allowed to get into the cells. If, through accident, this occurs, the acid in such cells must be thrown away and new electrolyte used. Matches or exposed flames of any kind must not come near the battery boxes, especially when the cells are charging. The gases thus given off are explosive when sufficiently concentrated. Temperatures higher than 100° F. are to be avoided, as the corrosion of the positive plates is accelerated. Low temperatures are not injurious, although they temporarily reduce the capacity of the battery.

Lead-Burning Outfits. In all batteries having permanently jointed connections the various joints are produced by melting of a portion of the parts to be joined by a process termed "leadburning," and forming a solid weld by means of heat to melt the lead, which may be produced with illuminating gas, hydrogen gas or the electric arc. The illuminating gas outfit is the simplest and can be used to advantage wherever that gas is available. It consists of a special-burning tip and a mixing valve. A supply