The block heater on a diesel engine helps to keep a vehicle's coolant and oil at a warmer temperature. This enables the engine to start more quickly and operate more efficiently than usual in cold weather conditions.
The block heater is normally installed as a replacement to one of the core plugs of the engine. As a result, it is able to keep the coolant and the oil at a warmer temperature simultaneously.
At the higher temperature, the coolant and oil are less viscous and thick. This makes it easier to circulate these fluids when the engine is turned on.
As a result, the vehicle starts and warms up more efficiently. Also, the engine attains the operating temperature more quickly. This in turn enables the effective functioning of the passenger compartment heater, improves engine component lubrication and offers greater fuel economy and engine performance.