• Established in 1908, Ambac International, formerly American Bosch, is the manufacturer of diesel fuel injection systems for heavy duty commercial and military applications. Original equipment manufacturers of engines still use their designs. The American Bosch nozzle nuts are 3-inches long and on the nozzle tip there is a hand printed drilling code. These nozzles are a part of a fuel distribution system and have many specifications.
  
  

Plunger

• Located above the pump camshaft of the fuel injection system, the plunger operates at crankshaft speed on four-cycle engines. This component is actuated by a camshaft and tappet arrangement.
  
  

Pump Camshaft

• The pump camshaft is located at the base of the fuel injection system and features the gearing for fuel distribution. Support for the pump camshaft is provided by a bushing type bearing on the governor end and a ball roller bearing on the driven end. Fuel distributed through the nozzle of the fuel injection system flows to the pump camshaft. The pump camshaft controls exhaust smoke of various fuels. It's equipped with a smoke limit cam within the mechanical centrifugal advance unit.
  
  

Mechanical Centrifugal Advance Unit

• The mechanical centrifugal advance unit has a pump camshaft. The unit houses a smoke limit cam and is driven clockwise at crankshaft speed. It plays an essential role in controlling the exhaust smoke of several fuels during the fuel delivery process from the nozzle to the pump camshaft.
  
  

Nozzle Valve Body

• The injection pump injects pressurized fuel into the top of the nozzle valve body. Then, the fuel passes through a passage in the body and nozzle spring retainer. Fuel fills an annular groove in the top face of the nozzle. The fuel is eventually directed around the nozzle valve via two passages in the nozzle valve body. Once the fuel reaches a predetermined pressure, the spring force expands and injection occurs.
  
  

Fuel Density Compensator

• The fuel density compensator works with different fuels. These fuels contain a variety of viscosities and heat values. The fuel density compensator injects different quantities of fuel into the engine. This is regulated by the full load stop of the fuel pump. Viscosity is the indicator used to regulate fuel flow. Despite the engine speed or load range, the fuel pressure is regulated at a constant of 20 pounds per square inch (psi) when the compensator injects fuel into the fuel regulator.