Fig. 220 Testing jar for leaks, using a 15-watt lamp in series with test circuitFig. 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 circuitThis 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 coilA 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 coilThe 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 JarsThe 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 assembling process made difficult.Repairing the CaseFig. 224 Washing sediment from Jars. Water supply controlled by foot valveThe 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 cock.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 brass 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.REASSEMBLING THE BATTERYReassembling the ElementsTake a negative group and put it on edge on a board, with post away from you, and lower edge toward you. Mesh a positive in the negative group. The groups are now ready for the separators. Take six moist separators from your stock. Slip one into position from the bottom in the middle of the group, with the grooved side toward the positive plate, spreading the plates slightly if necessary. Take another separator, slip it into position on the opposite side of the positive against which your first separator was placed. In this way, put in the six separators, with the grooved side toward the positives, working outward in both directions from the center, Fig. 225. The grooves must, of course, extend from the top to the bottom of the plate. Now grasp the element in both hands, and set it right side up on the block, giving it a slight jar to bring the bottoms of the plates and separators on a level.Fig. 225 Inserting separatorsNow grasp the element in both hands, and set it right side up on the block, giving it a slight jar to bring the bottoms of the plates and separators on a level.Next take a cover, and try it on the posts, Fig. 226. Pull the groups apart slightly, if necessary, before inserting any more separators, so that the cover fits exactly over the posts, Fig. 227. See that the separators extend the same distance beyond each side of the plates. You may take a stick, about 10 inches long, 1 1/2 inches wide, and 7/8 inch thick, and tap the separators gently to even them up. A small wood plane may be used to even up the side edges of wood separators. If you put in too many separators before trying on the cover, the plates may become so tight that you may not be able to shift them to make the cover fit the posts or you may not be able to shift the separators to their proper positions. It is therefore best to Put in only enough separators to hold the groups together and so they can be handled and yet remain in their proper position when set up on the block. Without separators, the posts will not remain in position.Fig. 226 Trying on a coverFig. 227 Shifting groups to make cover fitWith the element reassembled, and the remaining separators in their proper positions, see that all the plates are level on bottom, and no foreign matter sticking to them. Place the element in box shown in Fig. 219 to keep clean. Reassemble the other elements in exactly the same way, and put them in the box. The elements are now ready to be put in the jars.Putting Elements in JarsSteam the jars in the steamer for about five minutes to soften them somewhat, so that there will be no danger of breaking a jar when you put in the elements.With the case ready, look for the "+", "P" or "POS" mark on it. (Cases which are not marked in this way at the factory should be marked by the repairman before the battery is opened.) Place the case so that this mark is toward you. Grip an element near the bottom in order to prevent the plates from spreading, and put it in the jar nearest the mark, with the positive post toward you, next to the mark. Put an element in the next jar so that the negative post is toward you. Put an element in the third jar so that the positive post is toward you, and so on. The elements are correctly placed when each connecting strap connects a positive to a negative post. If the case has no mark on it, reassemble exactly according to the diagram you made on the tag before you opened the battery. Set the jars so that the posts are exactly in line so that the cell connectors will fit.Fig. 228 Tightening a loose element by placing a separator against outside negativeIf an element fits loosely in the jar, it must be tightened. The best way to do this is to put one or more separators on one or both sides of the elements before putting it in the jar, Fig. 228. If you leave the elements loose in the jars, the jolting of the car will soon crack the sealing compound, and you will have a "slopper" on your hands.If element fits very tight, be sure that the corners of the plate straps have been rounded off and trimmed flush with outside negatives. Be sure also that there is no compound sticking to the inside of jars. Take care not to break the jar by forcing in a tight fitting element when the jar is cold and stiff.Filling Jars with Electrolyte or Putting on the CoversWith all the elements in place in the jars, one of two things may be. done. First, the jars may be filled with electrolyte and the covers then sealed on, or the covers may first be sealed on and the jars then filled with electrolyte. Each method has its advantages and disadvantages. If the jars are first filled with electrolyte, acid may be splashed on the tipper parts of the jars and sealing made very difficult.On the other hand, if the electrolyte is first poured in, the charged negatives will not become hot, and sealing compound which runs into the jar will be chilled as soon as it strikes the electrolyte and will float on top and do no harm. If the covers are sealed before any electrolyte is added, it will be easier to do a good sealing job, but the negatives will heat up. Furthermore, any sealing compound which runs into the jar will run down between the plates and reduce the plate area.If care is taken to thoroughly dry the upper parts of the jars, add the electrolyte before sealing on the covers.Use 1.400 AcidIf you have followed the directions carefully, and have therefore freed all the shorts, have thoroughly charged the plates, have washed and pressed the negative groups, have washed the positives, have then added any new plates which were needed, and have put in new separators, use 1.400 specific gravity electrolyte. This is necessary because washing the plates removed some of the acid, and the new separators will absorb enough acid so that the specific gravity after charging will be about 1.280.The final specific gravity must be between 1.280 and 1.300. In measuring the specific gravity the temperature must be about 70°F., or else corrections must be made. For every three degrees above 70°, add one point (.001) to the reading you obtain on the hydrometer. For every three degrees under 70°, subtract one point (.001) from the reading you obtain on the hydrometer. For instance, if you read a specific gravity of 1.275 and find that the temperature of the electrolyte is 82°F., add ((82-70)/3 = 4)Example formula to determine specific gravityfour points (1.275 + .004), which gives 1.279, which is what the specific gravity of the electrolyte would be if its temperature were lowered to 70°. The reason this is done is that when Ave speak of an electrolyte of a certain specific gravity, say 1.280, we mean that this is its specific gravity when its temperature is 70°F. We must therefore make the temperature correction if the temperature of the electrolyte is much higher or lower than 70°F.Putting on The CoversThis operation is a particular one, and must be done properly, or you will come to grief. Get the box containing the covers and connectors for the battery you are working on; take the covers, and clean them thoroughly. There are several ways to clean them. If you have gasoline at hand, dip a brush in it and scrub off the compound. The covers may also be cleaned off with boiling water, but even after you have used the hot water, it will be necessary to wipe off the covers with gasoline. Another way to soften any compound which may be sticking to them, is to put the covers in the Battery Steamer and steam them for about ten minutes. This will also heat the covers and make them limp so that they may be handled without breaking.If the covers fit snugly all around the inside of the jars so that there is no crack which will allow the compound to run down on the elements, all is well and good. If, however, there are cracks large enough to put a small, thin putty knife in, you must close them. If the cracks are due to the tops of the jars being bent out of shape, heat the tops with a soft flame until they are limp, (be careful not to burn them). Now, with short, thin wedges of wood, (new dry separators generally answer the purpose), crowd down on the outside edges of the jar, until you have the upper edge of jars straight and even all around. If the jars are set in compound, take a hot screwdriver and remove the compound from between the jar and case near the top. If the cracks between cover and jar still remain, calk them with asbestos packing, tow, or ordinary wrapping string. Do not use too much packing;--just enough to close the cracks is sufficient. When this is done, see that the top of the case is perfectly level, so that when the compound is poured in, it will settle level all around the upper edge of the case.Sealing CompoundsThere are many grades of compounds (see page 149), and the kind to use must be determined by the type of battery to be sealed. There is no question but that a poor grade used as carefully as possible will soon crack and produce a slopper. A battery carelessly sealed with the best compound is no better.The three imperative conditions for a permanent lasting job are:1. Use the best quality of the proper kind of compound for sealing the battery on hand.2. All surfaces that the compound comes in contact with must be free from acid and absolutely clean and dry.3. The sealing must be done conscientiously and all details properly attended to step by step, and all work done in a workmanlike manner.With respect to sealing, batteries may be divided into two general classes. First, the old type battery with a considerable amount of sealing compound. This type of battery generally has a lower and an upper cover, the vent tube being attached or removable, depending on the design. The compound is poured on top of the lower cover and around the vent tube, and the top covers are then put on. Most of the batteries of this type have a thin hard rubber sleeve shrunk on the post where the compound comes in contact with it; this hard rubber sleeve usually has several shallow grooves around it which increase its holding power. This is good construction, provided everything else is normal and the work properly done with a good stick-, compound. There are a few single cover batteries with connecting straps close to top of covers, and the compound is poured over the top of the straps. See Fig. 262.The second general type consists of single one-piece cover batteries that have small channels or spaces around the covers next to the jars into which the sealing compound is poured. This type of battery is the most common type.Fig. 229 Pouring compound on lower coversCompound in bulk or in thin iron barrels can be cut into small pieces with a hatchet or hand ax. To cut off a piece in hot weather, strike it a quick hard blow in the same place once or twice, and a piece will crack off. Directions for properly beating sealing compound will be found on page 150.Sealing Double Cover BatteriesThe following instructions apply to batteries having double covers. These are more difficult to seal than the single cover batteries. If you can seal the double cover batteries well, the single cover batteries will give you no trouble.Always start the fire under the compound before you are ready to use it, and turn the fire lower after it has melted, so as not to have it too hot at the time of pouring. If you have a special long nosed pouring ladle, fill it with compound by dipping in the pot, or by pouring compound from a closed vessel. If you heat the compound in an iron kettle, pour it directly into pouring ladle, using just about enough for the first pouring. The compound should not be too hot, as a poor sealing job battery will result from its use. See page 150.Before sealing, always wipe the surfaces to be sealed with a rag wet with ammonia or soda solution, rinsed with water, and wiped dry with a rag or waste. If you fail to do this the compound will not stick well, and a top leak may develop. Then run a soft lead burning flame over the surfaces to be sealed, in order to have perfectly dry surfaces. Remember that sealing compound will not stick to a wet surface.Fig. 230 First pouring of sealing compoundFig. 231 Cooling compound with electric fanPour compound on the lower covers, as in Fig. 229. Use enough to fill the case just over the tops of the jars, Fig. 230. Then pour the rest of the compound back in compound vessel or kettle. To complete the job, and make as good a job as possible, take a small hot lead burning flame and run it around the edges of case, tops of jars, and around the posts until the compound runs and makes a good contact all around. If you have an electric fan, let it blow on the compound a few minutes to cool it, as in Fig. 231. Then the compound used for the second pouring may be hotter and thinner than the first.Fill the pouring ladle with compound, which is thinner than that used in the first pouring, and pour within 1/16 inch of the top of the case, being careful to get in just enough, so that-after it has cooled, the covers will press down exactly even with the top of the case, Fig. 232. It will require some experience to do this, but you will soon learn just how much to use.As soon as you have finished pouring, run the flame all around the edges of the case and around the post, being very careful not to injure any of the vent tubes. A small, hot-pointed flame should be used. Now turn on the fan again to cool the compound.Fig. 232 Second pouring of sealing compoundWhile the compound is cooling, get the cell connectors and terminal connectors, put them in a two-quart granite stew pan, just barely cover with water, and sprinkle a tablespoon of baking soda over them. Set the stew pan over the fire and bring water to boiling point. Then pour the water on some spot on a bench or floor where the acid has been spilled. This helps to neutralize the acid and keep it from injuring the wood or cement. Rinse off the connectors and wipe them dry with a cloth, or heat them to dry them.Fig. 233 Pressing covers down to make them level with top of caseNow take the top covers, which must be absolutely clean and dry, and spread a thin coat of vaseline over the top only, wiping off any vaseline from the beveled edges. Place these covers right side up on a clean board and heat perfectly limp with a large, spreading blow torch flame. Never apply this flame to the under side of the top covers. The purpose is to get the covers on top of the battery absolutely level, and exactly even with the top of the case all around it, and to have them sticking firmly to the compound. There is not an operation in repairing and rebuilding batteries that requires greater care than this one, that will show as clearly just what kind of a workman you are, or will count as much in appearance for a finished job. If you are careless with any of the detail, if just one bump appears on top, if one top is warped, if one cover sticks above top of case, try as you may, you never can cover it up, and show you are a first-class workman. See that you have these four conditions, and you should not have any difficulty after a little experience:Fig. 234 Pressing covers down around posts to make them flush with top of case1. You must have just enough compound on top to allow the top covers to be pressed down exactly even with upper edge of case.2. The top covers must be absolutely clean and have a thin coat of vaseline over their top, but none on the bevel edge.3. A good sized spreading flame to heat quickly and evenly the tops to a perfectly limp condition without burning or scorching them.4. Procure a piece of 7/8-inch board 1-1/2 inches wide and just long enough to go between handles of battery you are working on. Spread a thin film of oil or vaseline all over it.Having heated the covers and also the top surface of the compound until it is sticky so that the covers may be put down far enough and adhere firmly to it, place the covers in position. Then press the covers down firmly with a piece of oiled wood, as in Fig. 233, applying the wood sidewise and lengthwise of case until the top of cover is exactly even with the top of the case. It may be necessary to use the wood on end around the vent tubes and posts as in Fig. 234, to get that part of the cover level. If the compound comes up between covers and around the edges of the case, and interferes with the use of the wood, clean it out with a screwdriver. You can then finish without smearing any compound on the covers.Fig. 235 Wiping bottom of spoon filled with sealing compoundFig. 236 Filling cracks around covers with sealing compoundWhen you have removed the excess compound from the cracks around the edges of the covers with the screwdriver, take a large iron spoon which has the end bent into a pouring lip, and dip up from 1/2 to 2/3 of a spoonful of melted compound (not too hot). Wipe off the bottom of the spoon, Fig. 235, and pour a small stream of compound evenly in all the cracks around the edges of the covers until they are full, as in Fig. 236. Do not hold the spoon too high, and do not smear or drop any compound on top of battery or on the posts. No harm is done if a little runs over the outside of the case, except that it requires a little time to clean it off. A small teapot may be used instead of the spoon. If you have the compound at the right temperature, and do not put in too much at a time, you will obtain good results, but you should take care not to spill the compound over covers or case.Fig. 237 Final operation of cleaning off excess compoundAfter the last compound has cooled, — this requires only a few minutes, — take a putty knife, and scrape off all the surplus compound, making it even with the top of the covers and case, Fig. .237. Be careful not to dig into a soft place in the compound with the putty knife. If you have done your work right, and have followed directions explicitly, you have scraped off the compound with one sweep of the putty knife over each crack, leaving the compound smooth and level. You will be surprised to see how finished the battery looks.Some workmen pour hot compound clear to the top of the case and then hurry to put on a cold, dirty top. What happens? The underside of the cover, coming in contact with the hot compound, expands and lengthens out, curling the top surface beyond redemption. As you push down one corner, another goes up, and it is impossible to make the covers level.Sealing Single Cover BatteriesSingle cover batteries are scaled in a similar manner. The covers are put in place before any compound is poured in. Covers should first be steamed to make them soft and pliable. The surfaces which come in contact with the sealing compound must be perfectly dry and free from acid. Before pouring in any compound, run a soft flame over the surfaces which are to be sealed , so as to dry them and warm them. Close up all cracks between Jars and covers as already directed. Then pour the cover channels half full of sealing compound, which must not be too thin. Now run a soft flame over the compound until it flows freely and unites with the covers and jars. Allow the compound to cool.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 ConnectorsWith 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 BatteryYou 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 CaseThe next operation is to thoroughly clean the case; scrape 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, andthickcoat 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 BatteryWith the battery completely assembled, 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 110°F., either cut down the charging current, or take the battery off charge long enough to allow the electrolyte to cool below 90°F.Adjusting the ElectrolyteIf 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 DischargeWhenever 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.
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.
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 assembling process made difficult.
Fig. 224 Washing sediment from Jars. Water supply controlled by foot valve
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 cock.
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 brass 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.
Take a negative group and put it on edge on a board, with post away from you, and lower edge toward you. Mesh a positive in the negative group. The groups are now ready for the separators. Take six moist separators from your stock. Slip one into position from the bottom in the middle of the group, with the grooved side toward the positive plate, spreading the plates slightly if necessary. Take another separator, slip it into position on the opposite side of the positive against which your first separator was placed. In this way, put in the six separators, with the grooved side toward the positives, working outward in both directions from the center, Fig. 225. The grooves must, of course, extend from the top to the bottom of the plate. Now grasp the element in both hands, and set it right side up on the block, giving it a slight jar to bring the bottoms of the plates and separators on a level.
Fig. 225 Inserting separators
Now grasp the element in both hands, and set it right side up on the block, giving it a slight jar to bring the bottoms of the plates and separators on a level.
Next take a cover, and try it on the posts, Fig. 226. Pull the groups apart slightly, if necessary, before inserting any more separators, so that the cover fits exactly over the posts, Fig. 227. See that the separators extend the same distance beyond each side of the plates. You may take a stick, about 10 inches long, 1 1/2 inches wide, and 7/8 inch thick, and tap the separators gently to even them up. A small wood plane may be used to even up the side edges of wood separators. If you put in too many separators before trying on the cover, the plates may become so tight that you may not be able to shift them to make the cover fit the posts or you may not be able to shift the separators to their proper positions. It is therefore best to Put in only enough separators to hold the groups together and so they can be handled and yet remain in their proper position when set up on the block. Without separators, the posts will not remain in position.
Fig. 226 Trying on a cover
Fig. 227 Shifting groups to make cover fit
With the element reassembled, and the remaining separators in their proper positions, see that all the plates are level on bottom, and no foreign matter sticking to them. Place the element in box shown in Fig. 219 to keep clean. Reassemble the other elements in exactly the same way, and put them in the box. The elements are now ready to be put in the jars.
Steam the jars in the steamer for about five minutes to soften them somewhat, so that there will be no danger of breaking a jar when you put in the elements.
With the case ready, look for the "+", "P" or "POS" mark on it. (Cases which are not marked in this way at the factory should be marked by the repairman before the battery is opened.) Place the case so that this mark is toward you. Grip an element near the bottom in order to prevent the plates from spreading, and put it in the jar nearest the mark, with the positive post toward you, next to the mark. Put an element in the next jar so that the negative post is toward you. Put an element in the third jar so that the positive post is toward you, and so on. The elements are correctly placed when each connecting strap connects a positive to a negative post. If the case has no mark on it, reassemble exactly according to the diagram you made on the tag before you opened the battery. Set the jars so that the posts are exactly in line so that the cell connectors will fit.
Fig. 228 Tightening a loose element by placing a separator against outside negative
If an element fits loosely in the jar, it must be tightened. The best way to do this is to put one or more separators on one or both sides of the elements before putting it in the jar, Fig. 228. If you leave the elements loose in the jars, the jolting of the car will soon crack the sealing compound, and you will have a "slopper" on your hands.
If element fits very tight, be sure that the corners of the plate straps have been rounded off and trimmed flush with outside negatives. Be sure also that there is no compound sticking to the inside of jars. Take care not to break the jar by forcing in a tight fitting element when the jar is cold and stiff.
With all the elements in place in the jars, one of two things may be. done. First, the jars may be filled with electrolyte and the covers then sealed on, or the covers may first be sealed on and the jars then filled with electrolyte. Each method has its advantages and disadvantages. If the jars are first filled with electrolyte, acid may be splashed on the tipper parts of the jars and sealing made very difficult.
On the other hand, if the electrolyte is first poured in, the charged negatives will not become hot, and sealing compound which runs into the jar will be chilled as soon as it strikes the electrolyte and will float on top and do no harm. If the covers are sealed before any electrolyte is added, it will be easier to do a good sealing job, but the negatives will heat up. Furthermore, any sealing compound which runs into the jar will run down between the plates and reduce the plate area.
If care is taken to thoroughly dry the upper parts of the jars, add the electrolyte before sealing on the covers.
If you have followed the directions carefully, and have therefore freed all the shorts, have thoroughly charged the plates, have washed and pressed the negative groups, have washed the positives, have then added any new plates which were needed, and have put in new separators, use 1.400 specific gravity electrolyte. This is necessary because washing the plates removed some of the acid, and the new separators will absorb enough acid so that the specific gravity after charging will be about 1.280.
The final specific gravity must be between 1.280 and 1.300. In measuring the specific gravity the temperature must be about 70°F., or else corrections must be made. For every three degrees above 70°, add one point (.001) to the reading you obtain on the hydrometer. For every three degrees under 70°, subtract one point (.001) from the reading you obtain on the hydrometer. For instance, if you read a specific gravity of 1.275 and find that the temperature of the electrolyte is 82°F., add ((82-70)/3 = 4)
Example formula to determine specific gravity
four points (1.275 + .004), which gives 1.279, which is what the specific gravity of the electrolyte would be if its temperature were lowered to 70°. The reason this is done is that when Ave speak of an electrolyte of a certain specific gravity, say 1.280, we mean that this is its specific gravity when its temperature is 70°F. We must therefore make the temperature correction if the temperature of the electrolyte is much higher or lower than 70°F.
This operation is a particular one, and must be done properly, or you will come to grief. Get the box containing the covers and connectors for the battery you are working on; take the covers, and clean them thoroughly. There are several ways to clean them. If you have gasoline at hand, dip a brush in it and scrub off the compound. The covers may also be cleaned off with boiling water, but even after you have used the hot water, it will be necessary to wipe off the covers with gasoline. Another way to soften any compound which may be sticking to them, is to put the covers in the Battery Steamer and steam them for about ten minutes. This will also heat the covers and make them limp so that they may be handled without breaking.
If the covers fit snugly all around the inside of the jars so that there is no crack which will allow the compound to run down on the elements, all is well and good. If, however, there are cracks large enough to put a small, thin putty knife in, you must close them. If the cracks are due to the tops of the jars being bent out of shape, heat the tops with a soft flame until they are limp, (be careful not to burn them). Now, with short, thin wedges of wood, (new dry separators generally answer the purpose), crowd down on the outside edges of the jar, until you have the upper edge of jars straight and even all around. If the jars are set in compound, take a hot screwdriver and remove the compound from between the jar and case near the top. If the cracks between cover and jar still remain, calk them with asbestos packing, tow, or ordinary wrapping string. Do not use too much packing;--just enough to close the cracks is sufficient. When this is done, see that the top of the case is perfectly level, so that when the compound is poured in, it will settle level all around the upper edge of the case.
There are many grades of compounds (see page 149), and the kind to use must be determined by the type of battery to be sealed. There is no question but that a poor grade used as carefully as possible will soon crack and produce a slopper. A battery carelessly sealed with the best compound is no better.
The three imperative conditions for a permanent lasting job are:
1. Use the best quality of the proper kind of compound for sealing the battery on hand.
2. All surfaces that the compound comes in contact with must be free from acid and absolutely clean and dry.
3. The sealing must be done conscientiously and all details properly attended to step by step, and all work done in a workmanlike manner.
With respect to sealing, batteries may be divided into two general classes. First, the old type battery with a considerable amount of sealing compound. This type of battery generally has a lower and an upper cover, the vent tube being attached or removable, depending on the design. The compound is poured on top of the lower cover and around the vent tube, and the top covers are then put on. Most of the batteries of this type have a thin hard rubber sleeve shrunk on the post where the compound comes in contact with it; this hard rubber sleeve usually has several shallow grooves around it which increase its holding power. This is good construction, provided everything else is normal and the work properly done with a good stick-, compound. There are a few single cover batteries with connecting straps close to top of covers, and the compound is poured over the top of the straps. See Fig. 262.
The second general type consists of single one-piece cover batteries that have small channels or spaces around the covers next to the jars into which the sealing compound is poured. This type of battery is the most common type.
Fig. 229 Pouring compound on lower covers
Compound in bulk or in thin iron barrels can be cut into small pieces with a hatchet or hand ax. To cut off a piece in hot weather, strike it a quick hard blow in the same place once or twice, and a piece will crack off. Directions for properly beating sealing compound will be found on page 150.
The following instructions apply to batteries having double covers. These are more difficult to seal than the single cover batteries. If you can seal the double cover batteries well, the single cover batteries will give you no trouble.
Always start the fire under the compound before you are ready to use it, and turn the fire lower after it has melted, so as not to have it too hot at the time of pouring. If you have a special long nosed pouring ladle, fill it with compound by dipping in the pot, or by pouring compound from a closed vessel. If you heat the compound in an iron kettle, pour it directly into pouring ladle, using just about enough for the first pouring. The compound should not be too hot, as a poor sealing job battery will result from its use. See page 150.
Before sealing, always wipe the surfaces to be sealed with a rag wet with ammonia or soda solution, rinsed with water, and wiped dry with a rag or waste. If you fail to do this the compound will not stick well, and a top leak may develop. Then run a soft lead burning flame over the surfaces to be sealed, in order to have perfectly dry surfaces. Remember that sealing compound will not stick to a wet surface.
Fig. 230 First pouring of sealing compound
Fig. 231 Cooling compound with electric fan
Pour compound on the lower covers, as in Fig. 229. Use enough to fill the case just over the tops of the jars, Fig. 230. Then pour the rest of the compound back in compound vessel or kettle. To complete the job, and make as good a job as possible, take a small hot lead burning flame and run it around the edges of case, tops of jars, and around the posts until the compound runs and makes a good contact all around. If you have an electric fan, let it blow on the compound a few minutes to cool it, as in Fig. 231. Then the compound used for the second pouring may be hotter and thinner than the first.
Fill the pouring ladle with compound, which is thinner than that used in the first pouring, and pour within 1/16 inch of the top of the case, being careful to get in just enough, so that-after it has cooled, the covers will press down exactly even with the top of the case, Fig. 232. It will require some experience to do this, but you will soon learn just how much to use.
As soon as you have finished pouring, run the flame all around the edges of the case and around the post, being very careful not to injure any of the vent tubes. A small, hot-pointed flame should be used. Now turn on the fan again to cool the compound.
Fig. 232 Second pouring of sealing compound
While the compound is cooling, get the cell connectors and terminal connectors, put them in a two-quart granite stew pan, just barely cover with water, and sprinkle a tablespoon of baking soda over them. Set the stew pan over the fire and bring water to boiling point. Then pour the water on some spot on a bench or floor where the acid has been spilled. This helps to neutralize the acid and keep it from injuring the wood or cement. Rinse off the connectors and wipe them dry with a cloth, or heat them to dry them.
Fig. 233 Pressing covers down to make them level with top of case
Now take the top covers, which must be absolutely clean and dry, and spread a thin coat of vaseline over the top only, wiping off any vaseline from the beveled edges. Place these covers right side up on a clean board and heat perfectly limp with a large, spreading blow torch flame. Never apply this flame to the under side of the top covers. The purpose is to get the covers on top of the battery absolutely level, and exactly even with the top of the case all around it, and to have them sticking firmly to the compound. There is not an operation in repairing and rebuilding batteries that requires greater care than this one, that will show as clearly just what kind of a workman you are, or will count as much in appearance for a finished job. If you are careless with any of the detail, if just one bump appears on top, if one top is warped, if one cover sticks above top of case, try as you may, you never can cover it up, and show you are a first-class workman. See that you have these four conditions, and you should not have any difficulty after a little experience:
Fig. 234 Pressing covers down around posts to make them flush with top of case
1. You must have just enough compound on top to allow the top covers to be pressed down exactly even with upper edge of case.
2. The top covers must be absolutely clean and have a thin coat of vaseline over their top, but none on the bevel edge.
3. A good sized spreading flame to heat quickly and evenly the tops to a perfectly limp condition without burning or scorching them.
4. Procure a piece of 7/8-inch board 1-1/2 inches wide and just long enough to go between handles of battery you are working on. Spread a thin film of oil or vaseline all over it.
Having heated the covers and also the top surface of the compound until it is sticky so that the covers may be put down far enough and adhere firmly to it, place the covers in position. Then press the covers down firmly with a piece of oiled wood, as in Fig. 233, applying the wood sidewise and lengthwise of case until the top of cover is exactly even with the top of the case. It may be necessary to use the wood on end around the vent tubes and posts as in Fig. 234, to get that part of the cover level. If the compound comes up between covers and around the edges of the case, and interferes with the use of the wood, clean it out with a screwdriver. You can then finish without smearing any compound on the covers.
Fig. 235 Wiping bottom of spoon filled with sealing compound
Fig. 236 Filling cracks around covers with sealing compound
When you have removed the excess compound from the cracks around the edges of the covers with the screwdriver, take a large iron spoon which has the end bent into a pouring lip, and dip up from 1/2 to 2/3 of a spoonful of melted compound (not too hot). Wipe off the bottom of the spoon, Fig. 235, and pour a small stream of compound evenly in all the cracks around the edges of the covers until they are full, as in Fig. 236. Do not hold the spoon too high, and do not smear or drop any compound on top of battery or on the posts. No harm is done if a little runs over the outside of the case, except that it requires a little time to clean it off. A small teapot may be used instead of the spoon. If you have the compound at the right temperature, and do not put in too much at a time, you will obtain good results, but you should take care not to spill the compound over covers or case.
Fig. 237 Final operation of cleaning off excess compound
After the last compound has cooled, — this requires only a few minutes, — take a putty knife, and scrape off all the surplus compound, making it even with the top of the covers and case, Fig. .237. Be careful not to dig into a soft place in the compound with the putty knife. If you have done your work right, and have followed directions explicitly, you have scraped off the compound with one sweep of the putty knife over each crack, leaving the compound smooth and level. You will be surprised to see how finished the battery looks.
Some workmen pour hot compound clear to the top of the case and then hurry to put on a cold, dirty top. What happens? The underside of the cover, coming in contact with the hot compound, expands and lengthens out, curling the top surface beyond redemption. As you push down one corner, another goes up, and it is impossible to make the covers level.
Single cover batteries are scaled in a similar manner. The covers are put in place before any compound is poured in. Covers should first be steamed to make them soft and pliable. The surfaces which come in contact with the sealing compound must be perfectly dry and free from acid. Before pouring in any compound, run a soft flame over the surfaces which are to be sealed , so as to dry them and warm them. Close up all cracks between Jars and covers as already directed. Then pour the cover channels half full of sealing compound, which must not be too thin. Now run a soft flame over the compound until it flows freely and unites with the covers and jars. Allow the compound to cool.
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.
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.
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.
The next operation is to thoroughly clean the case; scrape 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, andthickcoat 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.
With the battery completely assembled, 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 110°F., either cut down the charging current, or take the battery off charge long enough to allow the electrolyte to cool below 90°F.
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.
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.