The exhaust system of a diesel engine includes components such as a turbocharger and an exhaust manifold which can have very high internal temperatures (e.g., any surface having a temperature above 135°C). In accordance with the invention the components subject to the high temperatures are coated with at least a first layer of thermally insulating material and a second layer overlying the first layer to provide surface protection. So coated, the temperature of the outer coated surfaces of these components is brought below an undesirably high level. Also, selected ones of the components may be water cooled and/or have a fitted jacket and/or be placed within an explosion proof enclosure. The input fuel line may also include a magnetic explosion proof fuel economizer to control the combustion process and reduce the internal temperature.