Toyota Corolla 1970-1987 Repair Guide

Battery

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FLUID LEVEL/SPECIFIC GRAVITY



Except Maintenance-Free Batteries

See Figures 1, 2 and 3

Most vehicles covered by this information were originally equipped with an unsealed, serviceable battery. These batteries require periodic inspection and service to assure proper operation. Check the battery fluid level on all serviceable batteries at least once a month, more often in hot weather or during extended periods of travel. The electrolyte level should be between the indicator lines on the side of the see-through battery casing. If no marks can be found on the battery, the electrolyte level should be even with the bottom of each cell's split ring. Be sure to check all 6 battery cells, not just one or two of them. If necessary, add distilled water to the battery in order to raise the electrolyte level in any cell which is low.

The specific gravity should be checked at least once a year using a hydrometer (an inexpensive tool available from many sources, including auto parts stores). The hydrometer has a squeeze bulb at one end and a nozzle at the other. Battery electrolyte is sucked into the hydrometer until the float is lifted from its seat. The specific gravity is then read by noting the position of the float. Generally, if after charging, the specific gravity between any two cells varies more than 50 points (0.050), the battery is bad and should be replaced. Most batteries should read between 1.20-1.26 at room temperature.



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Fig. Fig. 1: On most batteries check the fluid level using indicator lines located on the side of the battery casing



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Fig. Fig. 2: If no indicator lines are provided, electrolyte level for each cell should be even with the bottom of the split ring



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Fig. Fig. 3: On all serviceable batteries, a simple float type hydrometer may be used to check specific gravity

After checking the specific gravity, clean and tighten the clamps, then apply a thin coat of petroleum jelly to the terminals. This will help to retard corrosion. The terminals can be cleaned with a stiff wire brush or with an inexpensive terminal cleaner designed for this purpose.

If distilled water is added during freezing weather, the car should be driven several miles to allow the electrolyte and water to mix. Otherwise the battery could freeze.

If the battery becomes corroded, a solution of baking soda and water will neutralize the corrosion, then the solution should be rinsed from the battery using cold water. Before applying the solution, make sure that the fluid caps are securely in place in order to prevent contaminating the electrolyte.

Some batteries were equipped with a felt terminal washer. This should be saturated with engine oil approximately every 6,000 miles. This will help to retard corrosion.

If a fast charger is used while the battery is in the car, disconnect the battery before connecting the charger.

Keep flame or sparks away from the battery, especially when charging it; the battery gives off explosive hydrogen gas

Maintenance-Free Batteries

Some vehicles may be equipped with a maintenance-free battery. These batteries are especially popular with the aftermarket and any car whose battery has been replaced may wind up with one. Sealed maintenance-free batteries do not require normal attention as far as fluid level checks are concerned. However, the terminals require periodic cleaning, which should be performed at least once a year.

The sealed top battery cannot be checked for charge by checking the specific gravity using a hand-held hydrometer since there is no provision for access to the electrolyte. Instead, the built-in hydrometer must be used in order to determine the current state of charge.

Sealed batteries usually have a decal which gives instructions on how to read the indicator eye. If this decal is present on refer to it in order to determine battery condition. If the decal is not present, a few general rules may be followed. For most sealed batteries a light eye indicates a battery with sufficient fluid (though for some a yellow eye means the battery is in need of a charge while a green eye indicates a sufficient electrical charge). If the eye is dark, the electrolyte fluid is probably too low and the battery should be replaced. Many automotive parts stores that specialize in replacement batteries are also equipped to test the battery and will be happy to double check your findings.

CABLES AND CLAMPS



See Figures 4, 5, 6 and 7

In order to avoid the possibility of accidentally grounding the car's electrical system always remove the negative battery cable first. Failure to do so could allow a spark to occur exploding battery gasses and cause personal injury

Once a year, the battery terminals and the cable clamps should be cleaned. Loosen the clamps and remove the cables, negative cable first. On batteries with posts on top, the use of a puller specially made for this purpose is recommended. These are inexpensive, and are usually available in auto parts stores. Side terminal battery cables are secured with a bolt.



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Fig. Fig. 4: A puller will make clamp removal easier on post battery terminals

Clean the cable clamps and the battery terminals with a wire brush, until all corrosion, grease, etc. is removed and the metal is shiny. It is especially important to clean the inside of the clamp thoroughly, since a small deposit of foreign material or oxidation will prevent a sound electrical connection and could inhibit both starting or charging. Special tools are available for cleaning these parts, one type for conventional batteries and another type for side terminal batteries.



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Fig. Fig. 5: Special tools are also available to clean the battery terminals and clamps on side terminal batteries

Before installing the cables, loosen the battery hold-down clamp or strap, remove the battery and check the battery tray. Clear it of any debris, and check it for soundness. Rust should be wire brushed away, and the metal given a coat of anti-rust paint. Reposition the battery and tighten the hold-down clamp or strap securely, but be careful not to overtighten the retainer and crack the battery case.

After the clamps and terminals are clean, reinstall the cables, negative cable last. Never hammer on the clamps to install. Tighten the clamps securely, but do not distort them. Give the clamps and terminals a thin external coat of grease after installation, to retard corrosion.



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Fig. Fig. 6: The underside of this special battery tool has a wire brush to clean post terminals



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