Many diesel engines have a three-prong male connector to plug in when the block heater is needed. This plug can get corroded and dirty over time, as it typically hangs over the engine, which could cause it to malfunction. To remedy this, I cut the female end off an old extension cord to use as a cover. Just plug the block-heater connector into the extension-cord connector. It’s easy to do, works perfectly and protects the plug like a snug-fitting jacket.
Jerry Vinson | College Station, Texas