1.2 CYLINDER HEAD Copper injector tubes extending through the cylinder head water jacket are required for the fuel injectors. The tubes are directly exposed to the coolant. An O-ring seals the injector tube upper end in the recess. The lower end of the injector tube must be expanded and flared during the installation process to contain a tight fit in the firedeck bore. A beveled seat machined in the tube provides a compression-tight seal when the injector is seated, as well as affording effective heat transfer facilitating injector cooling. Refer to section 2.4.
Fuel galleries machined into the head supply fuel under fuel pump pressure to all injectors, and excess fuel is returned to the fuel tank. The fuel gallery outlet (restricted) fitting is installed in the rear of the cylinder head. See Figure 1-25. Figure 1-25 Fuel Gallery Inlet and Outlet Fittings (Rev. 2005) All information subject to change without notice. 1-34 6SE483 0507 Copyright © 2005 DETROIT DIESEL CORPORATION