All General Motors vehicles have a "maintenance free" battery as standard equipment, eliminating the need for fluid level checks and the possibility of specific gravity tests. However, the battery does require some attention.
Once a year, the battery terminals and the cable clamps should be cleaned. Remove the side terminal bolts and the cables, negative cable first. 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 there will prevent a sound electrical connection and inhibit either starting or charging. Special tools are available for cleaning the side terminal clamps and terminals.
Before installing the cables, loosen the battery hold-down clamp, remove the battery, and check the battery tray. Clear it of any debris and check it for corrosion. Rust should be wire-brushed away, and the metal given a coat of anti-rust paint. Install the battery and tighten the hold-down clamp securely, but be careful not to over tighten, which will crack the battery case.
After the clamps and terminals are clean, reinstall the cables, negative cable last. Give the clamps and terminals a thin external coat of grease after installation, to retard corrosion.
Check the cables at the same time that the terminals are cleaned. If the cable insulation is cracked or broken, or if the ends are frayed, the cable should be replaced with a new cable of the same length and gauge.
See Figures 1 and 2
The sealed top battery cannot be checked for charge in the normal manner, since there is no provision for access to the electrolyte. The battery has a label containing the model, cold cranking amps, load test amps and replacement number affixed to it. To check the condition of the battery proceed as follows:
Check the built in hydrometer on top of the battery:
- If a green dot appears in the middle of the indicator eye on top of the battery , the battery is sufficiently charged.
- If the indicator eye is clear or light yellow, the electrolyte fluid is too low and the battery must be replaced.
- If the indicator eye is dark, the battery has a low charge and should be charged.
Load test the battery:
- Connect a battery load tester and a voltmeter across the battery terminals (the battery cables should be disconnected from the battery).
- Apply a 300 ampere load to the battery for 15 seconds to remove the surface charge. Remove the load.
Wait 15 seconds to allow the battery to recover. Apply the appropriate test load, as specified:
730 Battery (std. V8) - Test load: 260 amperes
Take a voltage reading at the end of 15 seconds of load. Disconnect the load.
- Check the results against the following chart. If the battery voltage is at or above the specified voltage for the temperature listed, the battery is good. If the voltage falls below what's listed, the battery should be replaced.
CHARGING THE BATTERY
- To charge a sealed terminal battery out of the car, install adapter kit ST-1201 or 1846855 or equivalent.
- Make sure that all charger connections are clean and tight.
- Charge the battery until the indicator eye shows a green dot. (It may be necessary to tip the battery from side to side to get the green dot to appear after charging.) The battery should be checked every half hour while charging.
When it becomes necessary to replace the battery, select a battery with a rating equal to or greater than the battery originally installed. Details on battery removal and installation are covered in Engine & Engine Rebuilding .