1999 LAND ROVER DEFENDER oil temperature

LUBRICANTS, FLUIDS AND CAPACITIES
3
INFORMATION CAPACITIES
The following capacity figures are approximate and are provided as a guide only.
Capacities (approx.)* Litres Pints
Engine sump oil - Td5 7.20...................................................... 12.67
Extra when refilling after fitting new filter 1.00.......................... 1.76
Manual gearbox 2.38............................................................... 4.19
Transfer gearbox oil 2.30......................................................... 4.00
Front differential 1.70............................................................... 3.00
Rear differential
90 Models 1.70............................................................... 3.00
110 Models 2.26............................................................. 4.00
Power steering box and reservoir LHD 2.90............................ 5.00
Power steering box and reservoir RHD 3.40............................ 6.00
Swivel pin housing oil/grease (each) 0.35................................ 0.60
Fuel tank usable fuel
90 Models 60.00............................................................... 13.20 gall
110 & 130 Models 75.00................................................... 16.50 gall
Cooling system - Td5 13.00....................................................... 22.88
Washer bottle 3,0................................................................... 5.28
NOTE: * All levels must be checked by dipstick or level plugs as applicable.
ANTI-FREEZE
PERCENTAGE CONCENTRATION - 50%
PROTECTION - LOWER TEMPERATURE LIMIT
Complete protection
Vehicle may be driven away immediately from cold,
-33°C (-36°F).
Safe limit protection
Coolant in semi-frozen state. Engine may be started
and driven away after warm-up period, -41°C (-42°
F).
Lower protection
Prevents frost damage to cylinder head, block and
radiator. Thaw out before starting engine, -47°C (-53°
F).
CAUTION: Anti-freeze content must never
be allowed to fall below 50% otherwise
damage to the engine is liable to occur.
Also, anti-freeze content should not exceed 60%
as this will greatly reduce the cooling effect of the
coolant.RECOMMENDED FUEL
Diesel fuel oil, distillate, diesel fuel, automotive gas or
Derv to British standard 2869, Class A1 or A2
Using diesel fuel with a class rating lower than stated
above could seriously impair vehicle performance.
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12ENGINE
20
DESCRIPTION AND OPERATION Oil filter housing thermostat
1.Circlip
2.Thermostat end cap
3.Oil seal
4.Thermostatic valve5.Return spring
6.Oil filter housing
7.Threaded insert
The oil filter housing contains a thermostatically controlled valve to control the direction and proportion of oil flow
through the oil cooler matrix. When the oil temperature is cool, the centre spindle of the thermostatic element is
compressed. In this condition the valve completely seals the passage to the turbocharger feed tapping and flow is
directed through the oil filter adaptor housing, passing from the outlet of the full-flow filter to the cylinder block via
the rear oil return gallery in the oil cooler housing. A proportion of the oil flow from the right hand filter outlet port is
passed through to the oil cooler matrix to supply the turbocharger oil feed line.
When the oil temperature rises, the heated wax in the thermostat causes the thermostat centre spindle to rise and
push against the housing end cap, compressing the valve spring further and so opening the valve. In this
condition, oil flow from the outlet side of the full-flow filter is allowed to pass directly to the turbocharger oil feed
line and reverses the flow through the oil cooler matrix, which now delivers a proportion of cooled oil flow to the
cylinder block via the outlet port at the right hand side of the oil cooler housing.
The filter canister contains a by-pass valve which opens when the engine is cold or if the filter becomes blocked.
The by-pass valve opens when a pressure drop of greater than 1.6 kg/cm
2(157 kPa, 23 lbf/in2) is experienced.
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ENGINE
25
DESCRIPTION AND OPERATION CYLINDER HEAD COMPONENTS
The cylinder head components are described below:
Cylinder head
The cylinder head is of aluminium construction. It is not possible to reface the cylinder head if it becomes worn or
damaged. An alloy camshaft carrier is bolted directly to the upper surface of the cylinder head. Two dowels are
included in the cylinder head upper face for correct location of the camshaft carrier.
The EU3 cylinder head has a single internal fuel rail for delivering fuel to the injectors and an external fuel pipe for
returning spill fuel back to the fuel connector block. Therefore, pre EU3 and EU3 cylinder heads are not
interchangeable.
CAUTION: The cylinder head incorporates drillings for the fuel injection system, any
contamination which enters these drillings could cause engine running problems or injector
failure. It is therefore, essential that absolute cleanliness is maintained when carrying out work on
the cylinder head.
The camshaft carrier and cylinder head assembly is attached to the cylinder block by twelve cylinder head
retaining bolts which pass through the camshaft carrier and the cylinder head to secure the assembly to the
cylinder block.
CAUTION: The valve heads, tips of the injectors and glow plugs protrude below the face of the
cylinder head and will be damaged if the cylinder head is stored face down.
The camshaft is located between the cylinder head and the camshaft carrier, and the bearing journals are line
bored between the two components to form a matched pair.
CAUTION: Always fit plugs to open connections to prevent contamination.
The valve guides and valve seat inserts are sintered components which are an interference fit to the cylinder
head. The cylinder head machining also provide the locations for the electronic unit injectors, glow plugs, hydraulic
lash adjusters, finger followers and low pressure fuel rail.
Cooling to the cylinder head is provided by coolant flow through a water jacket machined into the cylinder head.
Drillings through the block provide lubrication channels for pressurised oil supply to cylinder head components
such as the lash adjusters, finger followers, rocker arms and camshaft bearings.
A coolant outlet elbow is fitted to the front LH side of the cylinder head to allow flow of coolant from the cylinder
head back to the radiator. A metal gasket is used to seal the joint between the water outlet elbow and the cylinder
head. A coolant temperature sensor is located in a port in the side of the water outlet elbow for monitoring coolant
temperature.
A stub pipe is connected at the front RH side of the cylinder block above the timing cover which connects a pipe to
supply oil to the vacuum pump. The timing chain tensioner adjuster is screwed in a thread in the cylinder head at a
location on the front RH side of the engine below the oil feed port for the vacuum pump.
An access hole for the camshaft gear is included at the front of the cylinder head which is sealed with a plastic
plug and rubber’O’ring. A press-fit core plug for the chain chest is located on the front face of the cylinder head.
A press-fit core plug for the cylinder head water jacket is located at the rear of the cylinder head and a threaded
brass plug for the water jacket is located on the LH side of the cylinder head beneath the exhaust manifold
assembly.
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12ENGINE
26
DESCRIPTION AND OPERATION Fuel connector block
Type A - Non EU3 Models - Engine Serial No. Prefixes 10P to 14P
Type B - EU3 Models - Engine Serial No. Prefixes 15P to 19P
1.Fuel connector block assembly
2.Outlet stub pipe
3.Stub pipe - to fuel cooler4.Fuel temperature sensor
5.Fuel pressure regulator
6.Spill return fuel connection (EU3 models only)
A cast and machined aluminium alloy fuel connector block assembly is located at the rear RH side of the cylinder
head, attached by three flanged bolts. A metal gasket is used to seal the faces between the fuel connector block
and the cylinder head, which must be replaced every time the fuel connector block is removed.
CAUTION: The cylinder head incorporates drillings for the fuel injection system, any
contamination which enters these drillings could cause engine running problems or injector
failure. It is therefore, essential that absolute cleanliness is maintained when carrying out work on
the cylinder head.
CAUTION: The valve heads, tips of the injectors and glow plugs protrude below the face of the
cylinder head and will be damaged if the cylinder head is stored face down.
Camshaft carrier
The cast aluminium alloy camshaft carrier is bolted to the cylinder head by thirteen screws. The camshaft carrier
and cylinder head assembly is attached to the cylinder block by twelve cylinder head retaining bolts which pass
through the camshaft carrier and the cylinder head to secure the assembly to the cylinder block.
The carrier is machined together with the cylinder head to form a matched pair for carrying the camshaft.
Non-return valve
A non-return valve is located at the front, bottom LH side of the cylinder head. The non-return valve prevents oil
from draining from the lash adjusters and is an integral component within the cylinder head and is
non-serviceable.
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ENGINE
35
DESCRIPTION AND OPERATION 1.To cylinder block main gallery (from rear of oil cooler housing)
2.Oil cooler housing
3.Oil pressure switch
4.Full-flow filter
5.Centrifuge filter
6.Return to sump
7.Flow from oil pump (via cylinder block)
8.Oil cooler matrix
When the engine temperature is below 74°C, the thermostat in the full-flow filter adaptor housing is closed and a
proportion of the oil flow to the main oil gallery is diverted to the oil cooler to supply an oil feed to the turbocharger
bearings. Oil passes through the oil cooler to the front gallery in the oil cooler housing where there is a tapping to
connect the feed pipe to the turbocharger. Oil used by the turbocharger bearings is returned to the sump through
an oil drain pipe which connects to a port in the LH side of the cylinder block.
The remainder of the oil flow leaving the full-flow filter outlet is passed into the cylinder block via a port at the rear
of oil cooler rear gallery.
When the oil temperature rises above 74°C the thermostat in the full-flow filter housing begins to open to allow a
proportion of the oil from the full-flow filter to pass through the oil cooler before it reaches the main oil gallery in the
cylinder block. In this instance, oil supply to the turbocharger bearings is fed directly from the full-flow filter without
first passing through the oil cooler. Between 74°C and 88°C the thermostat valve plunger opens by about 9 mm
(0.3 in) to allow proportionally more oil to flow through the oil cooler before being passed to the cylinder block main
oil delivery gallery. Above 88°C the thermostat valve continues to open by about 1mm (0.03 in) for every 10°C
increase in temperature until the valve is fully open, when all the oil flow to the cylinder block is forced to pass to
the cylinder block via the oil cooler.
An oil pressure switch is located in a port in the rear gallery of the oil cooler housing to sense the oil pressure level
before flow enters the main oil gallery in the engine block. A warning lamp in the instrument cluster is switched on
if the oil pressure is detected as being too low.
Drillings from the cylinder block main oil gallery direct oil to the crankshaft main bearings and cross drillings in the
crankshaft direct oil to the big-end bearings. An additional five drillings in the cylinder block supply oil at reduced
pressure to the oil squirt jets for piston cooling and gudgeon pin lubrication.
Oil supply from the cylinder block is then passed to the cylinder head galleries through a non-return valve which is
included as an integral item in the lower face of the cylinder head.
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12ENGINE
18
REPAIR
35.Remove 2 bolts and remove acoustic cover from
rear of cylinder head.
36.FitLRT-12-138to suitable lifting chains and
connect to lifting eyes on engine.
37.Remove 2 nuts from RH and LH front engine
mountings.
38.Fit trolley jack to support gearbox.
39.With assistance raise chains and remove engine
from vehicle.Refit
40.With assistance, raise engine from bench and
position in vehicle.
41.With assistance, align engine to gearbox input
shaft.
42.Position 2 upper bolts securing gearbox housing
to engine and tighten to50 Nm (37 lbf.ft).
43.Lower engine onto mountings and tighten nuts to
85 Nm (63 lbf.ft).
44.RemoveLRT-12-138from engine.
45.Fit and tighten bolt securing engine closing panel
to gearbox.
46.Raise vehicle on ramp.
47.Fit bolts securing gearbox housing to engine and
tighten to50 Nm (37 lbf.ft).
48.Lower ramp.
49.Fit acoustic cover to rear of cylinder head and
tighten bolts.
50.Position coolant hose to engine oil cooler and
secure clip.
51.Position PAS pump and tighten bolts to25 Nm
(18 lbf.ft).
52.Position PAS pulley and tighten bolts to25 Nm
(18 lbf.ft).
53.Position A/C compressor and tighten bolts to25
Nm (18 lbf.ft).
54.Route engine harness beneath inlet manifold
and connect multiplugs to oil pressure switch,
A/C compressor, and ECT sensor.
55.Fit and tighten bolts securing engine harness to
camshaft carrier.
56.Connect multiplug to alternator.
57.Connect battery lead to alternator and tighten
nut.
58.Clean CKP sensor and mating face.
CAUTION: If originally fitted:- Fit spacer to
CKP sensor.
59.Using a new’O’ring, fit CKP sensor, tighten bolt
to10 Nm (7 lbf.ft).
60.Connect CKP sensor multiplug.
61.Connect multiplugs to EGR solenoid, inlet
manifold sensor, injector harness, fuel
temperature sensor and CKP sensor.
62.Connect glow plug leads.
63.Connect multiplug to condensor cooling fan.
64.Connect vacuum hose to EGR valve.
65.Connect EGR vacuum hose to vacuum pipe.
66.Position pipe to vacuum pump and secure pipe
to acoustic cover clips.
67.Position fuel cooler. Apply Loctite 242 to bolts
and tighten to18 Nm (13 lbf.ft).
68.Disconnect fuel hose from connector block and
connect to fuel cooler.
69.Connect fuel hoses to fuel cooler and connector
block on cylinder head.
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EMISSION CONTROL
7
DESCRIPTION AND OPERATION CRANKCASE EMISSION CONTROL
All internal combustion engines generate oil vapour and smoke in the crankcase as a result of high crankcase
temperatures and piston ring and valve stem blow-by. A closed crankcase ventilation system is used to vent
crankcase gases back to the air induction system and so reduce the emission of hydrocarbons.
Gases from the crankcase are drawn into the inlet manifold to be burnt in the combustion chambers with the fresh
air/fuel mixture. The system provides effective emission control under all engine operating conditions.
Crankcase gases are drawn through the breather port in the top of the camshaft cover and routed through the
breather hose and breather valve on the flexible air intake duct to be drawn into the turbocharger intake for
delivery to the air inlet manifold via the intercooler.
An oil separator plate is included in the camshaft cover which removes the heavy particles of oil before the
crankcase gas leaves via the camshaft cover port. The rocker cover features circular chambers which promote
swirl in the oil mist emanating from the cylinder head and camshaft carrier. As the mist passes through the series
of chambers between the rocker cover and oil separator plate, oil particles are thrown against the separator walls
where they condense and fall back into the cylinder head via two air inlet holes located at each end of the rocker
cover.
The breather valve is a pressure depression limiting valve which progressively closes as engine speed increases,
thereby limiting the depression in the crankcase. The valve is of moulded plastic construction and has a port on
the underside which plugs into a port in the flexible air duct. A port on the side of the breather valve connects to
the camshaft cover port by means of a breather hose which is constructed from a heavy duty braided rubber hose
which is held in place by hose clips. A corrugated plastic sleeve is used to give further protection to the breather
hose. The breather valve is orientation sensitive, and’TOP’is marked on the upper surface to ensure it is
mounted correctly.
It is important that the system is air tight. Hose connections to ports should be checked and the condition of the
breather hose should be periodically inspected to ensure it is in good condition.
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18ENGINE MANAGEMENT SYSTEM
24
DESCRIPTION AND OPERATION GLOW PLUGS
The 4 glow plugs are located in the engine block on the inlet side, in cylinders 1 to 4. Cylinder 5 has no glow plug.
The glow plugs are a vital part of the engine starting strategy. The purpose of the glow plugs are:
Assist cold engine start.
Reduce exhaust emissions at low engine load/speed.
The main part of the glow plug is a tubular heating element that protrudes into the combustion chamber of the
engine.The heating element contains a spiral filament that is encased in magnesium oxide powder. At the tip of
the tubular heating element is the heater coil. Behind the heater coil and connected in series is a control coil. The
control coil regulates the heater coil to ensure that it does not overheat and cause a possible failure. The glow
plug circuit has its own control relay, located underneath the RH front seat.
Pre-heat is the length of time the glow plugs operate prior to engine cranking. The ECM controls the pre-heat time
of the glow plugs based on battery voltage and coolant temperature information via the glow plug relay.
Post-heat is the length of time the glow plugs operate after the engine starts. The ECM controls the post-heat time
based upon ECT information. If the ECT fails the ECM will operate pre-post heat time strategies with default
values from its memory. In this case, the engine will be difficult to start.
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