Land Rover Engine V8 4 4 L 2005 Capewell Manual

							 
 
The camshafts are manufactured in chilled cast iron. Five aluminium alloy caps retain each camshaft. Location 
numbers, 0 to 4 for the intake camshaft and 5 to 9 for the exhaust camshaft, are marked on the outer faces of the 
caps. 
 
Sensor Ring 
 
 
 
Timing rings for each camshaft position sensor are located at the rear of both intake camshafts. A flat, machined near 
the front of each camshaft, enables the camshafts to be locked during the valve timing procedure. 
 
Camshaft Position Sensor 
Item Part Number Description 
1 -Inlet camshaft
2 -Sensor ring
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The camshaft position sensors are installed in each cylinder head at the rear of the intake camshaft. It is a variable 
reluctance sensor that provides an input to the ECM regarding the position of the camshaft. For additional 
information, refer to   Electronic Engine Controls (303-14B Electronic Engine Controls - 4.4L) 
 
 
Inlet and Exhaust Valves 
Each cylinder head incorporates dual overhead camshafts operating four valves per cylinder via solid shimless 
aluminium alloy valve lifters. 
 
The lightweight valve gear provides good economy and noise levels. Valve head diameters are 31mm (1.220 in) for 
the exhaust and 35mm (1.378 in) for the intake. All valves have 5mm (0.197 in) diameter stems supported in sintered 
metal seats and guide inserts. Collets, valve collars and spring seats locate single valve springs on both intake and 
exhaust valves. Valve stem seals are integrated into the spring seats. 
 
 
 
 
Fuel Injectors 
   CAUTION : Due to slight variations in length, the valves are not interchangeable between marques 
(Land Rover, Jaguar and Aston Martin). 
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Eight, top fed, 12-jet, fuel injectors are installed in the fuel rails. The injectors are electromagnetic solenoid valves 
controlled by the ECM. Two O-rings seal each injector to manifold interface. The fuel jets from the injectors are 
directed onto the back of the intake valves. For additional information, refer to   Electronic Engine Controls (303-14B 
Electronic Engine Controls - 4.4L) 
 
 
VARIABLE VALVE TIMING (VVT) 
The continuously VVT unit turns the intake camshaft in relation to the primary chain to advance and retard the timing.
 
The system improves low and high-speed engine performance, engine idle quality and exhaust emission. 
 
The VVT system changes the phasing of the intake valves, relative to the fixed timing of the exhaust valves, to alter: 
 
zthe mass of air flow into the engines cylinders,  
zand the engines torque response and emissions.  
The VVT unit uses a vane device to control the camshaft angle (refer to VVT operation). The system operates over a 
range of 48° and is advanced or retarded to the optimum angle within this range. 
 
The ECM controls the VVT, using engine speed and load, and engine oil temperature signals to calculate the 
appropriate camshaft position. For additional information, refer to   Electronic Engine Controls (303-14B Electronic 
Engine Controls - 4.4L) 
 
 
The continuous VVT system provides the following advantages: 
 
zReduces engine emissions and fuel consumption by further optimising the camshaft timing, this improves the 
engines internal exhaust gas re-circulation (EGR) effect over a wider operating range  
zImproves full-load torque characteristics as the camshaft timing is optimised at all engine speeds for superior 
volumetric efficiency  
zImproves fuel economy by optimising torque over the engines speed range.  
This system also has the added benefits of operating at a lower oil-pressure and faster response time when 
compared to a non-VVT system. 
 
Variable Valve Timing Operation
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The VVT unit is a hydraulic actuator mounted on the end of the intake camshaft, which advances or retards the intake 
camshaft timing and thereby alters the camshaft to crankshaft phasing. The oil control solenoid, controlled by the 
ECM, routes oil pressure to either the advance or retard chambers located either side of the three vanes interspersed 
within the machined housing of the unit. 
 
The VVT unit is driven by the primary chain and rotates relative to the exhaust camshaft sprocket. When the ECM 
requests the camshaft timing to advance, the oil control solenoid is energized moving the shuttle valve to the relevant 
position to allow engine oil pressure, via a filter, into the VVT units advance chambers. When the camshaft timing is 
requested to retard, the shuttle valve moves position to allow oil pressure to exit the advance chambers, while 
simultaneously routing the oil pressure into the retard chambers. 
 
When directed by the ECM, the VVT unit will be set to the optimum position between full advance and retard for a 
particular engine speed and load. This is achieved when the ECM sends the energising signal to the oil control 
solenoid until the target position is met. At this point, the energizing signal is reduced to hold the solenoid position, 
and as a result the position of the shuttle valve. This function is under closed-loop control, where the ECM will assess 
any decrease in shuttle-valve oil-pressure, via signals from the camshaft position sensor. The ECM will increase the 
energizing signal, when required, to maintain the shuttle-valve hold position. 
 
Engine oil properties and temperature can affect the ability of the VVT mechanism to follow demand changes to the 
cam phase angle. At very low oil-temperatures, movement of the VVT mechanism is sluggish due to increased 
viscosity, and at high oil-temperatures the reduced viscosity may impair operation if the oil pressure is too low. To 
maintain satisfactory VVT performance, an increased capacity oil pump is installed, plus an engine oil temperature 
sensor to enable monitoring by the ECM. The VVT system is normally under closed-loop control except in extreme 
temperature conditions, such as cold starts below 0°C. At extremely high oil-temperatures, the ECM may limit the 
amount of VVT advance to prevent the engine from stalling when returning to idle speed. 
 
The VVT does not operate when engine oil-pressure is below 1.25 bar, as there is insufficient pressure to release the 
VVT units internal stopper pin. This usually occurs when the engine is shutting-down and the VVT has returned to the 
retarded position. The stopper pin locks the camshaft to the VVT unit to ensure camshaft stability during the next 
engine start-up. 
 
LUBRICATION SYSTEM 
Item Part Number Description 
A -Retarded
B -Advanced
1 -Engine oil pressure
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General 
Oil is drawn from the reservoir in the oil pan and pressurised by the oil pump. The output from the oil pump is then 
filtered, cooled and distributed through internal oil passages. 
 
All moving parts are lubricated by pressure or splash oil. Pressurised oil is also provided for operation of the variable 
valve timing units and the timing gear chain tensioners. 
 
The oil returns to the oil pan under gravity. Large drain holes through the cylinder heads and cylinder block ensure 
the quick return of the oil, reducing the volume of oil required and enabling an accurate check of the contents soon 
after the engine stops. 
 
System replenishment is through the oil filler cap on the bank B camshaft cover. 
 
With the exception of the pump, all oil system components are installed on the structural sump. 
 
Oil Pick-up 
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The fabricated steel oil pick-up is immersed in the oil reservoir to provide a supply to the oil pump during all normal 
vehicle attitudes. A mesh screen in the inlet prevents debris from entering the oil system. 
 
Oil Pump 
 
 
The oil pump is installed on the crankshaft at the front of the engine. The pump inlet and outlet ports align with oil 
passages in the bedplate. 
 
The pumping element is an eccentric rotor, which is directly driven by flats on the crankshaft. An integral pressure 
relief valve regulates pump outlet pressure at 4.5 bar (65.25 psi). 
 
Oil Filter and Oil Pressure Switch
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The oil filter is a replaceable cartridge installed on an adapter. An internal bypass facility permits full flow bypass if the 
filter is blocked. 
 
The oil pressure switch connects a ground input to the instrument cluster when oil pressure is present. The switch 
operates at a pressure of 0.15 to 0.41 bar (2.2 to 5.9 psi). 
 
Oil Level Gauge 
 
 
The oil level gauge locates along the left side of the oil pan, supported in a tube installed in the sump. Two holes in 
the end of the gauge indicate the minimum and maximum oil levels. There is a difference of approximately 1.5 litres 
(1.58 US quart) between the two levels. 
 
EXHAUST MANIFOLD 
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The fabricated stainless steel twin skin exhaust manifolds are unique for each cylinder bank. The bank B manifold 
has a connection for the EGR transfer pipe. 
 
Spacers on the securing bolts allow the manifolds to expand and retract with changes of temperature while 
maintaining the clamping loads. 
 
Heat shields are integrated into the exhaust manifold gaskets. 
 
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