1999 JAGUAR S TYPE engine oil

V6 EngineAJ-V6/AJ28
13
Oil Distribution
(see illustration on page 14)
Oil distribution within the block and cylinder
heads is similar to that of the V8 engine, the main
differences being in the filter and cooler
arrangement and the method of supplying the
VVT system.
Oil is drawn from the sump through the strainer
by the crankshaft driven pump, passes through
the externally mounted filter and oil cooler and
returns to the block. Distribution is via the main
gallery and crankshaft oilways to the lower
crankcase components and via branch feeds to
the chain tensioners and then cylinder head
components. Extra oilways in the cylinder heads
provide a built-in feed for the VVT components
(see VVT section).
Oil Pump
The oil pump is of the inner/outer rotor type with
the directly driven inner rotor located via flats on
the crankshaft and the body of the pump bolted
to the cylinder block. The oil pressure relief valveis located in the lower LH side of the pump. An
oil pick-up tube and strainer is bolted to the
pump inlet and projects directly down to the
sump. Oil foaming is reduced by the windage tray
bolted to the underside of the bedplate.
D.303.1211
Lubrication System
OIL PUMP
D.303.1211

V6 Engine
14
J.303.1289
ENGINE OIL SUPPLY
J.303.1289
AJ-V6/AJ28
1. VVT oil feed
2. Bank 1 camshaft oil feeds
3. Bank 2 camshaft oil feeds
4. Oil cooler
5. Oil filter
6. Oil filter adaptor7. Oil pressure switch
8. EOT sensor
9. Oil pressure relief valve
10. Oil strainer
11. Oil pump
12. Timing chain tensioner oil feed
1
21
3
4
5
678
12
910
11
12

V6 EngineAJ-V6/AJ28
15
Oil Cooler and Filter Mounting
The oil filter and oil cooler are mounted slightly
away from the cylinder block on an aluminium
alloy adaptor which is an integral extension of the
LH engine mount. The oil filter is a replaceable
canister screw on type and the cooler is fixed by a
single through bolt to the adaptor. Both
components are connected to the cylinder block
through internal oilways in the adaptor casting
and via an interfacing filter mounting in the
block. A hollow bolt passes through the
adaptor/engine mount and screws into the centre
channel of the block filter mounting to provide
the oil return from the cooler to the cylinder
block.
The adaptor mounted oil cooler is an oil to water
heat exchanger and the coolant matrix is
connected via hoses into the main coolant system
at the radiator bottom hose (see Cooling System).
ENGINE OIL PRESSURE AND OIL TEMPERATURE SENSORS
D.303.1205
OIL COOLER AND FILTER ASSEMBLY
EOP Sensor
EOT Sensor
D.303.1205
D.303.1371
Engine Oil Pressure (EOP) and Oil
Temperature (EOT) Sensors
EOP and EOT sensors are fitted on the LH side of
the cylinder block in the return feed from the oil
cooler. The oil temperature is monitored to
provide data for the VVT system.
Oil Cooler
Hollow Bolt
Engine Mount/
Oil Cooler Adapter

V6 Engine AJ-V6/AJ28
16
Crankcase Ventilation
Full Load Ventilation
Breather outlets on each cam cover are connected
via hoses and a Tee junction to the intake duct to
provide full load crankcase ventilation.
Positive Crankcase Ventilation
Under closed or near closed throttle conditions,
engine breathing is mainly via the positive
crankcase ventilation (PCV) system. An oil
separator is bolted to the top of the engine block
between the cylinder banks and has an outlet
connected to the intake manifold via an in-line
PCV valve and hoses. The PCV valve has a spring
J.303.1286
FULL LOAD VENTILATION
D.303.1286
loaded plunger which opens under the intake
vacuum created at low throttle openings. When
the PCV valve is open, crankcase gases are drawn
through the separator, depositing oil droplets on
an internal baffle for return to the sump.
The PCV inlet tube to the manifold is heated by
the engine cooling system.
J.303.1290
POSITIVE CRANKCASE VENTILATION
D.303.1290
Oil Separator
PCV valve

V6 EngineAJ-V6/AJ28
19
Variable Valve Timing (VVT)
A VVT system is used to allow the phasing of the
inlet valve opening to be changed relative to the
fixed timing of the exhaust valves. Two positions
are used, 30û apart, with the advanced position
occurring at 30û BTDC and overlapping with the
exhaust opening. The system is similar to that
previously used on the AJ26 V8 engine but uses
different components and a different oil feed
arrangement.
The operating regime is controlled by the engine
management system in conjunction with the
variable geometry induction system so as to
optimise torque characteristics over the engine
speed/load range. The engine torque curve with
VVT operating points is shown in the section on
the Variable Intake System. The VVT system also
provides increased amounts of ÔinternalÕ EGR
under certain speed/load operating conditions.
VVT Oil Feed
The VVT/sprocket unit is fixed on the nose of the
inlet camshaft via a locating pin and hollow bolt
and is driven directly by the timing chain. Unlike
the VVT systems on the V8 engines, the oil feed
J.303.1288
VVT OIL FEED
J.303.1288
VVT Unit
VVT Oil
Control Valve
D.303.1361
VVT TIMING DIAGRAM
D.303.1361
Inlet Camshaft RetardedInlet Camshaft Advanced
Inlet opens TDC
Exhaust closes
11.5û ATDCInlet opens
30û BTDCExhaust closes
11.5û ATDC
TDC
Inlet closes
36û ABDC
Exhaust
opens 57.5û
BBDC Inlet closes
66û ABDCExhaust opens
57.5û BBDC41.5û Overlap 11.5û Overlap
Inlet Camshaft
Valve Overlap
Exhaust Camshaft

V6 Engine AJ-V6/AJ28
20to each VVT unit is supplied via fixed oilways in
the cylinder head and not through a separate
bush carrier. This arrangement requires a feed
through the camshaft side of the VVT unit from
the main cylinder head supply. The oil feed is
controlled by the VVT oil control valve, a solenoid
operated shuttle valve, which is bolted directly to
the cylinder head. From the oil control valve, the
flow is via the thrust bearing cap, through
drillings in the camshaft and then through the
hollow fixing bolt which secures the VVT unit.
Drain holes are provided at the rear (camside)
face of the VVT unit for any residual oil which has
seeped past the piston.
Operation
Operation is similar to that of the two stage V8
VVT system. With the oil control valve open, oil
pressure on the helical drive piston is increased,
rotating the cams to the advanced position.
When the valve closes, oil pressure reduces and
the return spring pushes the piston back to thefully retarded position.
The oil control valve is controlled by a 300Hz
PWM signal from the PCM which sets it to either
the fully open or fully closed position.
J.303.1306
VVT OPERATION
VVT Unit with
oil pressure
VVT oil
control valve
open
VVT oil
control valve
closed
VVT Unit with oil
pressure reduced
J.303.1306

Ignition System
V6 Engine AJ-V6/AJ28
30cylinder heads and the upper intake manifold
assembly.
The injectors are of the top fed, split spray type
and are supplied from a common fuel rail
assembly which bolts to the lower manifold. The
integral fuel rail consists of an upper delivery pipe
and a lower pipe with six takeoff feeds for the
injectors. The IP sensor is bolted to a flange at the
junction of the two pipes and has an electrical
connection to the fuel rail harness and a vacuum
feed from the intake manifold. A steel cross-over
pipe provides the coupling to the vehicle
mounted fuel line and also carries the EFT sensor,
on a bracket, and the de-pressurisation valve. The
cross-over pipe is connected to the fuel rail via a
semi-rigid length of pipe.
All fuel injectors and sensors use a common
electrical harness with a single multi-way
connection to the main engine harness.
Six coil-on-plug ignition units fit directly on to the
spark plugs. The ignition units are driven by the
PCM and do not contain integral amplifiers.
D.303.1206D.303.1206
COIL-ON-PLUG UNITS

V6 EngineAJ-V6/AJ28
31
J.303.1365
Engine Cooling
Cooling System
Engine cooling is via a conventional re-circulation
system between the engine assembly and front
mounted coolant to air radiator. Coolant flow is
from the front of the engine, dividing to pass
around each bank of cylinders towards the rear
and then flowing forward through the cylinder
heads. The coolant from the engine returns to the
top RH side of the radiator, by-pass circuit and
also provides the hot input feed to the cabin
V6 ENGINE COOLING SYSTEMheater system. The bottom hose feeds coolant
from the radiator via the thermostat to the
coolant pump and also provides the cooling
circuit for the oil. A differential pressure orifice in
the bottom hose causes a flow through the engine
mounted oil cooler.
A coolant reservoir system (or de-gas system) is
used which is similar to previous (pre 1998MY)
vehicles.
The reservoir bottle is mounted at the rear left
1. Radiator
2. Top hose
3. Bottom hose
4. Thermostat
5. Coolant Pump
6. Engine oil cooler7. Reservoir bottle
8. Electronic throttle
9. V6 engine
10. Heater control valve
11. Heater unit
12. Bleed valve
1
10
5
11
9
4
6
2
3
8
12
7
J.303.1365