Battery Tech Tip By Randy Rundle Vaseline, also known as petroleum jelly, works well to keep battery posts free of corrosion. After you have cleaned the posts and the cable ends using a battery terminal cleaner tool, reinstall the cables. Next put a light coating of Vaseline on top and around the cable clamps. The Vaseline will keep the terminals free of corrosion ensuring a positive start every time. Better yet you can upgrade to a sealed type battery like the Optima Brand of batteries. There will be no water to add and no posts to clean. Sealed batteries also eliminate the chances of spilling acid, and damaging the paint. Dielectric Grease Caution — DO NOT use dielectric electrical grease to keep battery posts free of corro- sion, as dielectric grease is an insulator and has a low melting point. When dielec- tric grease melts (caused by the heat gen- erated as the current passes through the posts) it changes into a liquid form and runs down between the battery post and the cable clamp. All will be well until you shut off the engine and everything cools down. When you go back to restart your car the battery will appear to be dead. In real- ity the current from the battery is not being allowed to pass through to the bat- tery cables. To correct the problem remove and clean both the cable ends and the battery posts with emery paper or a battery terminal cleaner tool and reinstall. That should restore your battery connec- tion. This mainly applies to the older batter- ies where you have to add water.