PRINCIPLES GASOLINE/DIESEL FUEL SYSTEMS - OD1620 - LESSON 2/TASK 2
PRESSURE-TIMED INJECTION SYSTEM.
(c) A return line from the PTG pump to the fuel tank is provided
(d) The PTG pump delivers controlled amounts of fuel to pressure-
timed delivery (PTD) injectors.
(e) Delivery of fuel to the PTD injectors is through a common-rail
type delivery line.
(f) A common-rail type return line connects the PTD injectors to
the fuel tank so that excess fuel may be diverted back to the fuel tank.
(2) PTV Injection Pump (figure 53 on the following page).
pump is driven directly by the engine at a one-to-one speed ratio. The pump
contains four main components. These four components and their operations
are described as follows: