Abstract: An internal combustion engine is provided including an injector having an injector body including a nozzle assembly having an annular outer surface. A cylinder head includes an injector mounting bore to receive the injector, and a lower sealing portion. The engine also includes an engine coolant passage formed in the cylinder head to receive engine coolant to remove heat from the cylinder head. The engine coolant passage opens into, and is fluidly connected to, the mounting bore to cause coolant in the coolant passage to contact the annular outer surface of the nozzle assembly. A lower seal is positioned between the lower sealing portion and the nozzle assembly to form a fluid seal.