Land Rover Common Rail System Crs Denso Manual

Operation Section1–16
CYLINDER RECOGNITION SENSOR {TDC (G) SENSOR}
• The cylinder recognition sensor {TDC (G) sensor} uses the alternating current voltage generated by the change in the
lines of magnetic force passing through the coil to send the output voltage to the ECU. This is the same for the engine
speed sensor installed on the engine side. A disc-shaped gear, which is provided in the center of the supply pump
camshaft, has cutouts that are placed at 120? intervals, plus an extra cutout. Therefore,...

Operation Section1–17
(4) Supply Pump Operation
Supply Pump Overall Fuel Flow
• The fuel is drawn by the feed pump from the fuel tank and sent to the pumping mechanism via the PCV. The PCV
adjusts the quantity of fuel pumped by the pumping mechanism to the necessary discharge quantity, and the fuel is
pumped to the rail via the delivery valve.
Fuel Discharge Quantity Control
• The fuel sent from the feed pump is pumped by the plunger. In order to adjust the rail pressure, the PCV controls the
discharge...

Operation Section1–18
3.2 HP2 Type
(1) Construction and Characteristics
• The supply pump is primarily composed of the two pumping mechanism (inner cam, roller, two plungers) systems,
the SCV (Suction Control Valve), the fuel temperature sensor, and the feed pump (vane type), and is actuated with
half the engine rotation.
• The pumping mechanism consists of an inner cam and a plunger, and forms a tandem configuration in which two sys-
tems are arranged axially. This makes the supply pump compact and...

Operation Section1–19
(2) Supply Pump Actuating Torque
• Because the pumping mechanism is a tandem configuration, its peak actuating torque is one-half that of a single
pump with the same discharge capacity.
Pumping
Pumping
Pumping SuctionPumping
Feed
Feed Plunger 2 Plunger 1
Torque (Oil Pumping Rate) Torque (Oil Pumping Rate)
 Composition
Single TypeTandem Type
Torque Pattern 
Solid Line    : Plunger 1
Broken Line: Plunger 2
Q000819E 

Operation Section1–20
(3) Exploded View
Pump Body
Feed PumpCamshaft
Inner Cam
Roller
Shoe
Delivery Valve
SCV (Suction Control Valve)
Check Valve Fuel Temperature Sensor Regulating Valve
Q000820E 

Operation Section1–21
(4) Component Part Functions
Feed Pump
• The feed pump is a four-vaned type that draws fuel from the fuel tank and discharges it to the pumping mechanism.
The rotation of the drive shaft causes the feed pump rotor to rotate and the vane to move by sliding along the inner
surface of the casing (eccentric ring). Along with the rotation of the rotor, the pump draws fuel from the fuel tank, and
discharges it to the SCV and the pumping mechanism. To keep the vane pressed against the...

Operation Section1–22
SCV: Suction Control Valve 
• A solenoid type valve has been adopted. The ECU controls the duration of the current applied to the SCV in order to
control the quantity of fuel drawn into the pumping mechanism. Because only the quantity of fuel required to achieve
the target rail pressure is drawn in, the actuating load of the supply pump decreases, thus improving fuel economy.
SCV ON
- When current is applied to the coil, it pulls the needle valve upward, allowing fuel to be drawn...

Operation Section1–23
Pumping Mechanism (Plunger, Inner Cam, Roller)
• The pumping mechanism is made up of the plunger, inner cam, and roller, and it draws in the fuel discharged by the
feed pump and pumps it to the rail. Because the drive shaft and the inner cam have an integral construction, the ro-
tation of the drive shaft directly becomes the rotation of the inner cam.
• Two plunger systems are arranged in series (tandem type) inside the inner cam. Plunger 1 is situated horizontally,
and plunger 2...

Operation Section1–24
Fuel Temperature Sensor
• The fuel temperature sensor is installed on the fuel intake side and utilizes the characteristics of a thermistor in which
the electric resistance changes with the temperature in order to detect the fuel temperature.
Check Valve
• The check valve, which is located between the SCV (Suction Control Valve) and the pumping mechanism, prevents
the pressurized fuel in the pumping mechanism from flowing back into the SCV.
Check Valve Open
- During fuel suction...

Operation Section1–25
(5) Supply Pump Operation
Supply Pump Overall Fuel Flow
• Fuel is suctioned by the feed pump from the fuel tank and sent to the SCV. At this time, the regulating valve adjusts
the fuel pressure to below a certain level. Fuel sent to the feed pump has the required discharge quantity adjusted by
the SCV and enters the pumping mechanism through the check valve. The fuel pumped by the pumping mechanism
is pumped through the delivery valve to the rail.
From Fuel Tank
Feed Pump...