coolant temperature LAND ROVER DEFENDER 1999 Workshop Manual

01INTRODUCTION
10
INFORMATION CROSS REFERENCE OF EMISSION SYSTEM
TERMINOLOGY
NEW TERM (ACRONYM)
Accelerator pedal (AP).................................................
Air cleaner (ACL)..........................................................
Air conditioning (A/C)...................................................
Battery positive voltage (B+)........................................
Closed loop (CL)..........................................................
Closed throttle position (CTP)......................................
Canister purge valve (CANPV)....................................
Data link connector (DLC)...........................................
Diagnostic trouble code (DTC).....................................
Distributor ignition (DI).................................................
Engine control module (ECM)......................................
Engine coolant level (ECL)...........................................
Engine coolant temperature (ECT)..............................
Engine speed (RPM)....................................................
Evaporative emission system (EVAP)..........................
Engine fuel temperature sensor (EFTS)......................
4th gear, 3rd gear etc. (4GR, 3GR)..............................
Fuel pump (FP)............................................................
Fan control module (FCM)...........................................
Generator (GEN)..........................................................
Ground (GND)..............................................................
Heated oxygen sensor (H02S)....................................
Idle air control (IAC)......................................................
Idle air control valve (IACV).........................................
Ignition control module (ICM).......................................
Intake air temperature (IAT).........................................
Manifold vacuum zone (MVZ)......................................
Mass air flow sensor (MAF).........................................
Open loop (OL)............................................................
Relay module (RM)......................................................
Solid state relay module (SSRM).................................
Three way catalytic converter (TWC)..........................
Throttle body (TB)........................................................
Throttle position sensor (TP)........................................
Transmission range (TR)..............................................
Wide open throttle (WOT)............................................OLD TERM (ACRONYM)
Throttle pedal (-)..........................................................
Air cleaner (-)...............................................................
Air conditioning (AC)....................................................
Battery plus, bat +, bat feed (B+).................................
Closed loop (-).............................................................
Closed throttle, idle position (-)....................................
Charcoal canister purge valve (-).................................
Serial link (-)................................................................
Fault code (-)...............................................................
Electronic ignition (-)....................................................
Electronic control unit (ECU)........................................
Coolant level (-)...........................................................
Coolant temperature (temp).........................................
Coolant temperature thermistor (-)..............................
Engine speed (rev/min)................................................
Evaporative loss system (ELC)...................................
Fuel temperature thermistor (-)....................................
Fourth gear, 3rd gear (-)..............................................
Fuel pump (-)...............................................................
Condenser fan timer (-)................................................
Alternator (-)................................................................
Ground, earth (B-)........................................................
Lambda (02) sensor (-)................................................
Idle speed control (ISC)................................................
Stepper motor (-).........................................................
Ignition module (-)........................................................
Intake temperature/ambient temperature (-)................
Manifold depression, vacuum (-).................................
Air flow meter (-)..........................................................
Fault code display unit (-)............................................
Open loop (-)...............................................................
Relay (-).......................................................................
Control unit (-)..............................................................
Catalyst, catalytic converter (CAT)..............................
Throttle housing (-)......................................................
Transmission gear (-)...................................................
Full throttle, wide open throttle (WOT).........................
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GENERAL SPECIFICATION DATA
3
INFORMATION FUEL SYSTEM - Td5
Type Direct injection from pressure regulated supply with.................................................................................
cooled return flow
Pressure regulator setting 4 bar (58 lbf.in
2) ................................................
Pump Electric two stage submersible................................................................................
Pump output
Low pressure 30 l/h (6.6 gal/h) at 0.5 bar (7.25 lbf.in
2) ..........................................................
High pressure 180 l/h (39.6 gal/h) at 4 bar (58 lbf.in2) ..........................................................
Max consumption 30 l/h (6.6 gal/h).............................................................
Injectors Electronic unit injectors...........................................................................
Injector normal operating pressure 1500 bar (21750 lbf.in
2) ..................................
Filter In-line canister filter/water separator with water.................................................................................
detection
COOLING SYSTEM - Td5
Type Pressurised spill return partial flow, thermostatically.................................................................................
controlled
Cooling fans 11 blade axial flow on viscous coupling and 11 blade.....................................................................
axial flow electric
Electric cooling fan switching points
On Vehicle speeds of 50 mph (80 km/h) and below while...........................................................................
ambient temperature is 28°C (82°F) or above
Off Vehicle speeds of 62.5 mph (100 km/h) and above or...........................................................................
ambient temperatures of 25°C (77°F) and below
Coolant pump Centrifugal impeller, belt driven from crankshaft...................................................................
Thermostat Waxstat with pressure relief valve.......................................................................
Thermostat opening temperature
Initial opening 82°C (179°F) ..........................................................
Fully open 96°C (204°F) ...............................................................
Expansion tank cap relief valve operating pressure 1.4 bar (20.3 lbf.in
2) .........
CLUTCH - Td5
Type Diaphragm spring, hydraulically operated with.................................................................................
self-centering pre-loaded release bearing
Drive plate diameter 267 mm.........................................................
Pressure plate diameter 270 mm...................................................
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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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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
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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17EMISSION CONTROL
8
DESCRIPTION AND OPERATION EXHAUST GAS RECIRCULATION
The exhaust gas recirculation (EGR) valve permits a controlled amount of exhaust gas to combine with the fresh
air entering the engine. The exhaust gas reduces the combustion temperature by delaying the fuel burning rate,
which assists in reducing the quantity of oxides of nitrogen.
On EU3 models, an EGR cooler is employed to further reduce the combustion temperature. By passing the
exhaust gas through a bundle of pipes flooded by coolant, the density of the exhaust gas going into the engine is
increased. This process further reduces the amount of NO
2in the exhaust.
Recirculation of too much exhaust gas can result in higher emissions of soot, HC and CO due to insufficient air.
The recirculated exhaust gas must be limited so that there is sufficient oxygen available for combustion of the
injected fuel in the combustion chamber. To do this the ECM is used to control the precise quantity of exhaust gas
to be recirculated in accordance with the prevailing operating conditions. Influencing factors include:
The mass of air flow detected by the MAF sensor.
The ambient air temperature detected by the AAP sensor. This is used to initiate adjustments to reduce the
amount of smoke produced at high altitudes.
The mass of air flow detected by the MAF sensor.
The ambient air temperature detected by the AAP sensor. This is used to initiate adjustments to reduce the
amount of smoke produced at high altitudes.
Other factors which are taken into consideration by the engine management system for determining the optimum
operating condition include:
Manifold inlet air temperature
Coolant temperature
Engine speed
Fuel delivered
The main components of the EGR system are as follows.
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18 - ENGINE MANAGEMENT SYSTEM
CONTENTS
Page
DESCRIPTION AND OPERATION
COMPONENT LOCATION 2...................................................................................
DESCRIPTION 5.....................................................................................................
ENGINE CONTROL MODULE (ECM) 6.................................................................
SENSOR - MASS AIR FLOW (MAF) 7....................................................................
SENSOR - AMBIENT AIR PRESSURE AND 8.......................................................
SENSOR - MANIFOLD ABSOLUTE PRESSURE 9................................................
SENSOR - ENGINE COOLANT TEMPERATURE 11.............................................
SENSOR - CRANKSHAFT SPEED AND 12...........................................................
SENSOR - THROTTLE POSITION (TP) 14............................................................
SENSOR - THROTTLE POSITION (TP) 15............................................................
ELECTRONIC UNIT INJECTOR (EUI) 18...............................................................
SENSOR - FUEL TEMPERATURE (FT) 20............................................................
RELAY - FUEL PUMP 21........................................................................................
RELAY - MAIN 21...................................................................................................
SWITCH - BRAKE PEDAL 22.................................................................................
SWITCH - CLUTCH PEDAL 22...............................................................................
MODULATOR - EXHAUST GAS REGULATOR (EGR) 23.....................................
WARNING LAMP - GLOW PLUG 23......................................................................
GLOW PLUGS 24...................................................................................................
TURBOCHARGER 26.............................................................................................
INTERCOOLER 27.................................................................................................
OPERATION 28......................................................................................................
REPAIR
ENGINE CONTROL MODULE (ECM) 1.................................................................
SENSOR - ENGINE COOLANT TEMPERATURE (ECT) 1....................................
SENSOR - CRANKSHAFT SPEED AND POSITION (CKP) 2................................
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ENGINE MANAGEMENT SYSTEM
3
DESCRIPTION AND OPERATION 1.Mass Air Flow (MAF) sensor.
2.Engine Coolant Temperature (ECT) sensor.
3.Glow plugs.
4.Manifold Absolute Pressure (MAP) / Inlet Air Temperature (IAT) sensor.
5.Fuel pump relay.
6.Engine Control Module (ECM).
7.Air Conditioning (A/C) and cooling fan relay.
8.Fuel Temperature (FT) sensor.
9.Crankshaft Speed and Position (CKP) sensor.
10.Electronic Unit Injectors (EUI).
11.Ambient Air Pressure (AAP) sensor.
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ENGINE MANAGEMENT SYSTEM
5
DESCRIPTION AND OPERATION DESCRIPTION
General
An engine control module (ECM) controls the five cylinder direct injection diesel engine, and works on the drive by
wire principal. This means there is no throttle cable, the ECM controls the drivers needs via a signal from the
Throttle Position (TP) sensor on the throttle pedal.
The ECM is a full authoritative diesel specific microprocessor that also incorporates features for air conditioning. In
addition, the ECM supplies output control for the Exhaust Gas Recirculation (EGR) and turbocharger boost
pressure. The ECM has a self diagnostic function, which is able to provide backup strategies for most sensor
failures.
The ECM processes information from the following input sources:
Mass Air Flow (MAF) sensor.
Ambient Air Pressure (AAP) sensor.
Manifold Absolute Pressure (MAP) / Inlet Air Temperature (IAT) sensor.
Engine Coolant Temperature (ECT) sensor.
Crankshaft Speed and Position (CKP) sensor.
Throttle Position (TP) sensor.
Fuel Temperature (FT) sensor.
Air conditioning request.
Air conditioning fan request.
Brake pedal switch.
Clutch pedal switch.
The input from the sensors constantly updates the ECM with the current operating condition of the engine. Once
the ECM has compared current information with stored information within its memory, it can make any adjustment
it requires to the operation of the engine via the following:
Air conditioning clutch relay.
Air conditioning cooling fan relay.
Electronic vacuum regulator solenoid.
Fuel pump relay.
Glow plug warning lamp.
Glow plugs.
Fuel injectors.
Main relay.
Turbocharger wastegate modulator.
Temperature gauge.
The ECM interfaces with the following:
Serial communication link.
Instrument pack.
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18ENGINE MANAGEMENT SYSTEM
6
DESCRIPTION AND OPERATION ENGINE CONTROL MODULE (ECM)
The ECM is made from aluminium alloy and is located under the RH front seat. The ECM has an interface of 72
pins via two connectors providing both input information and output control. The ECM receives information from
the sensors to inform it of the current state of the engine. The ECM then refers this information to stored values in
its memory and makes any changes to the operation of the engine necessary via the actuators. This is a rolling
process and is called adaptive strategy. By using this adaptive strategy the ECM is able to control the engine to
give optimum driveability throughout all operating conditions. There is no ECM self test, although the ECM saves
driveability data from the last journey. Power down of the ECM can take between 10 seconds and 10 minutes
dependent on coolant temperature.
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