Corvette Batteries - Em-Power-Ment

C1, C2, and C3 owners can skip this step. However, if there are radio station presets or security codes that could be lost when disconnecting the battery, connect a temporary battery before disconnecting either cable. A 9V battery with alligator clips suffices, but there are also inexpensive adapters that plug into the cigarette lighter. Just make sure it is not switched.

Take the cable off the negative terminal first. Although less of a concern on some Corvettes, this is a good habit to develop. Otherwise, if a wrench touches a grounded part while disconnecting the positive terminal first, an out-of-control arc welder is instantly created. After the negative cable is disconnected and moved safely away, it's safe to disconnect the positive side. Use a 5/16 six-sided socket or wrench for side terminals.

Remove the hold-down bracket. On a C3, a 1/2-inch socket on a long extension works best. If the bolt does not turn easily, slide underneath and apply penetrating oil to the exposed threads. Rusted parts can be protected with POR15, but don't allow it to get on any threads.

When you remove the battery, don't let it contact your clothes, carpet, or upholstery because the sulfuric acid may create holes a few days later. Clean the battery compartment, tray, and hold-down. Use baking soda and water to clean any acid deposits. Wear goggles or safety glasses and cover nearby carpet or upholstery when brushing off deposits.

Inspect for swollen cables, a sign that corrosion is under the insulating jacket. The C3 ground cable connection on the frame is also worth checking; it suffers exposure to water, salt, and road grime. The C3 ground cable is one of easiest to replace, as compared to the C3 positive cable, which is one of the most challenging to replace.

Install the battery and connect the cables, positive cable first. For side terminals, take care when starting the threads. It may be difficult to see when the bolt is straight, and the cable will tend to twist it. Apply high temp grease on the cable ends to prevent corrosion. The felt washers at auto parts stores are also good for post mounts, but not for side mounts.

Don't over-tighten side mount bolts, which can crack the case. Snug the bolt and then move the cable to see if it is tight. If the bolt is too long it can bottom out in the battery hole before tightening the cable. Install the clamp and make sure the battery can't move. Depending on the car, it might be easier to install the clamp before connecting the cables.

Wear safety glasses, as battery explosions are among the three most common accidental causes of blindness at home. A battery that I was asked to jump-start exploded, sending sulfuric acid onto the sidewalk and the building in front of the car. If nothing better is around, at least wear sunglasses or readers.

Checking voltage is a fast and easy way to learn about a battery's condition. After charging, a battery's voltage will remain artificially high, at over 13 volts, for a while. Wait 12 hours or more (or put the headlights on for a few minutes and then wait 10 minutes) and use a digital gauge to accurately read the resting voltage. A fully charged battery should read around 12.7 volts.

Charging voltage tells if the charging system is performing properly. With a fully charged battery, turn the headlights and AC or fan on high and hold the engine at a fast idle. The voltage measured at the battery should be in the 13.8- to 14.8-volt range for most vehicles.

Hygrometers are very useful for checking the condition of a battery that has removable caps. They can tell the state of charge in each battery cell. If one or more cells read less than the others, this is an early warning sign that the battery should be replaced. The eyedropper style is inexpensive, but make sure air bubbles don't attach to the colored balls, as this will cause false readings.

A load test employs an instrument that puts a high drain on the battery to detect problems that hygrometers and resting voltage miss. If the capacity of the battery has significantly decreased or if the connections between the plates or cells have deteriorated, the load test reveals this. LectricLimited's Load Tester also incorporates an analog voltmeter. Note that many auto parts stores will perform a load test, other battery tests, or alternator tests for free.