Why is that Semi plugged in?

November 7, 2014

Semi

As we are moving into the winter months, you may begin to see diesel pickups and semi-trucks plugged into power outlets. Yep. It’s a thing. I’m here to tell you why.

A diesel engine doesn’t use a spark plug like a gasoline engine to ignite the fuel that is being introduced in the cylinder; it uses heat and pressure made by the piston moving up and down inside the cylinder. That cylinder has to be a certain temperature to ignite the diesel fuel.

As we all know the colder it is outside the colder everything outside becomes, including the cylinder of your diesel engine. The colder the cylinder, the longer it takes for it to warm up, the longer it takes to start your truck. This is where plugging your diesel engine in comes into play.

The cord you are seeing is connected to a block heater inside the truck. This block heater warms up the engine coolant to around 85 degrees. This allows the cylinders to stay warm in cold weather allowing for faster and easier starts. Not to mention a nice warm heater when you start your truck.

Now you know what’s going on if you happen to see a big rig plugged in!