How to Remove & Change Car Battery Connectors

Car battery connectors can eventually corrode and rust to the point of crumbling. Corroded battery clamps give a bad connection to the battery post, which can prevent the car from starting even if the battery is fully charged. Replacement connectors are available at auto parts stores and many large department stores with an auto section. Changing the connectors will probably take less time than removing the old ones from the battery posts.

Things You'll Need

• Wrenches
• Wire cutters
• Hacksaw with metal-cutting blade
• Replacement battery connectors
• Rust remover in a spray can or white vinegar

Instructions

1. Spray rust remover on the battery posts to loosen the old connectors, or pour a tablespoon of white vinegar on each connector and allow to set for 30 minutes.

2. Use the wrenches to loosen the bolts securing the connectors to the battery posts, starting with the negative (black) cable. Turn the bolts counter-clockwise and wiggle the connectors back and forth to loosen and remove by lifting it straight up.

3. Cut the battery cables as close as possible to the old connectors using the wire cutters. If necessary, cut off the connectors with a metal-cutting hacksaw.

4. Strip 1/2 inch of insulation from each battery cable.

5. Loosen the retainer bolts on the new connectors and insert the bare wire for each battery cable into the hole in the connector. Tighten the retainer bolts to secure the cables to the connector

6. Place the positive cable connector over the positive battery post and the negative cable connector over the negative battery post.

7. Tighten the side bolts on the connectors using a wrench.

Tips & Warnings

• Try cleaning the battery posts and the connectors, especially the inside ring, using a piece of steel wool. This may solve the problem without having to replace the connectors.

• Keep hands and tools away from the battery posts while changing the connectors, taking care not to touch both terminals at the same time.

References

• Battery connector replacement
• Cleaning and replacing battery terminals