If the battery feels hot to the touch or smells like rotten eggs (sulfur), stop charging immediately. The battery may have a shorted cell.
: Do not plug the Selmar Turbo 4 into the wall outlet until the alligator clips are firmly clamped onto the battery terminals. Old Car Battery Charger - How to use it? | DIYnot Forums selmarturbo4batterychargerinstructions link
Before using your Selmarturbo 4 Battery Charger, please read and follow these safety precautions: If the battery feels hot to the touch