Jaguar AJ-V8 User Manual

Published by Service Communications, Jaguar Cars Limited

Publication Part No JJM 18 15 15/70, August 1996

Technical Guide

AJ-V8 Engine

and

5HP24 Transmission

Introduction

PrefaceAJ-V8/5HP24

This Technical Guide introduces the new AJ V8 engine and 5HP24 transmission installed in the XK8 Sports car. It is intended to give Jaguar Dealer workshop personnel an overview of their construction and operation, and is for information purposes only. The contents of this Technical Guide must not be used as a reference source for servicing procedures; all servicing procedures must be in accordance with the appropriate Service Manual.

This Technical Guide will not be updated. While every effort is made to ensure accuracy, changes may occur between going to press and the equipment being introduced to the market. Once the equipment is in service, details of changes can be obtained from Service Bulletins and revisions to the Service Manuals.

All rights reserved. No part of this publication may be reproduced, stored in a retrieval system or transmitted, in any form, electronic, mechanical, photocopying, recording or other means without prior written permission from the Service Division of Jaguar Cars Limited.

Contents AJ-V8/5HP24

Subject Page

Glossary

Abbreviations 2

Introduction 3

Engine

Basic Engine 5 Engine Cooling 17 Engine Lubrication 20 Variable Valve Timing 24 Air Intake System 27 Fuel System 33 Ignition System 35 Crankcase Ventilation 35 EGR System 37 Engine Accessories 38 Accessory Drive 39 Engine Harness 41 Engine Covers 42 Engine Specifications 43

Engine Management

ECM 45 Electronic Throttle 53 Fuel Pump 58 Fuel Injection 58 Ignition 59 EVAP System 60 Variable Valve Timing 61 EGR System 61 Engine Starting 61 HO2S Heaters 62 Instrument Cluster 62 A/C Compressor Clutch 62 Windshield and Backlight Heaters 62 Radiator Cooling Fans 62 Diagnostics 63

Transmission

Introduction 65 Technical Data 66 Gearshifting 66 Mechanical Description 66 Electrical Description 67

Transmission Management

Transmission Management 68

Service Tools

New Tools 72

GlossaryAJ-V8/5HP24

The following abbreviations are used in this document:

Abbreviation Description

ABS anti-lock braking system A/C air conditioning A/CCM air conditioning control module BPM body processor module BHP brake horse power ˚C degree Celsius CAN controller area network CDI cubic inch displacement DIN Deutsche Institut für Normung dc direct current DTC diagnostic trouble code ECM engine control module ECT engine coolant temperature EGR exhaust gas recirculation EMS engine management system EVAP evaporative emission ˚F degree Fahrenheit ft foot HO2S heated oxygen sensor in inch JDS Jaguar diagnostic system lb pound lbf.ft pound force feet kg kilogram km/h kilometer per hour kW kilowatt m meter MAFS mass air flow sensor MIL malfunction indicator lamp mph miles per hour mm millimeter ms millisecond Nm Newton meter NOx nitrous oxide OBD on-board diagnostics O2S oxygen sensor PAS power assisted steering PDU portable diagnostic unit psi pounds per square inch PTFE polytetrafluoroethane rpm revolutions per minute SAE Society of Automotive Engineers (USA) SCP standard corporate protocol TCM transmission control module USA United States of America V volt VSV vacuum solenoid valve

Introduction AJ-V8/5HP24

The AJ-V8 4.0 litre, engine is the first of a new family of Jaguar engines. Designed to give excellent performance, refinement, economy and low vibration levels it also conforms to the strictest emission legislation. Weighing only 200 kilograms (441 lb), the engine is shorter by 12 inches (300 mm) than the current AJ16 4.0 litre engine. Compression ratio is 10.75:1, with four valves per cylinder. The cylinder heads, block and bedplate are all cast aluminum. Cylinders have electro-plated bores which reduce piston friction, improve warm-up and oil retention. A variable valve timing system has been introduced to give improved low and high-speed engine performance and excellent idle quality. The valve gear is chain driven for durability. Low valve overlap improves engine idle speed and low residual fuel levels which improves combustion and reduces hydrocarbon emissions. The inlet manifold is a one-piece, composite moulding with integral fuel rails connecting to the eight side feed fuel injectors. Air flow into the engine is via an electronic throttle assembly. Movement of the throttle is controlled by sensors in the throttle assembly through the ECM. The engine has a low volume, high velocity, cooling system which achieves a very fast warm-up with reduced and even metal temperatures in the combustion chamber and increased bore temperatures. The generator, A/C pump, and PAS pump are mounted to the cylinder block on rigid cradle supports. Accessory drive is from a single, 7-ribbed vee belt. Hydraulic engine mounts minimise noise and vibration. A new engine management system adjusts fuel and ignition settings, monitors and controls exhaust emissions and provides an on-board diagnostic capability.

The transmission is a new ZF 5-speed, automatic, electronically controlled unit. The unit is oil filled for life so does not have an oil gauge (dipstick). Two driver selected modes are available, sport or normal. The TCM is programmed with cruise, traction, gradient, warm-up and hot mode features. It also provides an on-board diagnostic capability.

The engine and transmission meet OBDII USA environmental regulations. Default limp home modes for both engine and transmission are provided.

Engine AJ-V8/5HP24

Basic Engine

The AJ-V8 is an all new 90° V8 liquid cooled engine that gives refined and effortless performance. Constructed in aluminum alloy, the AJ-V8 introduces several innovative design features new to Jaguar engines, the most notable of these being:

• a bedplate

• nikasil coated cylinder bores

• fracture split connecting rods

• variable valve timing

• aluminum alloy valve lifters

• electronic throttle control.

303-056

EngineAJ-V8/5HP24

ENGINE STRUCTURE

ENGINE DATA LOCATIONS

303-052

303-001

Cylinder Block

The cylinder block is an "enclosed V" design, which provides an inherently rigid structure with good vibration levels. Nikasil (a composition of nickel and silicon) coated cylinder bores provide good friction, heat transfer and piston noise levels. A low volume coolant jacket improves warm-up times and piston noise levels; the longitudinal flow design of the jacket, with a single cylinder head coolant transfer port in each bank, improves rigidity and head gasket sealing. The right hand cylinder bank is designated as "A" bank, and the left hand as "B" bank. The cylinder bores of each bank are numbered from 1 to 4, starting from the front. Engine data is marked at three locations on the cylinder block. Component diameters are represented by alphabetical and numerical codes; keys to the codes are in the Service Manual.

1. Cylinder Head

2. Cylinder Block

3. Bed Plate

4. Structural Sump

Emissions Code

Serial Number

* Main Bearing Crankshaft Diameters * Connecting Rod Bearing Crankshaft Diameters * Cylinder Bore Diameters * Main Bearing Bore Diameters *

Engine AJ-V8/5HP24

CYLINDER BLOCK, CRANKSHAFT AND BEDPLATE

303-011

EngineAJ-V8/5HP24

Bedplate

The bedplate is a structural casting bolted to the bottom of the cylinder block to retain the crankshaft. The use of a bedplate further improves rigidity. Iron inserts, cast into the main bearing supports of the bedplate, minimise main bearing clearance changes due to heat expansion. Two hollow dowels align the bedplate with the cylinder block. Beads of sealant seal the joint between the bedplate and the cylinder block.

Crankshaft

Six counter-balance weights ensure good vibration levels from the four throw, five bearing crankshaft. Manufactured in cast iron, the crankshaft also has undercut and rolled fillets for improved strength. The main bearings are aluminum/tin split plain bearings. An oil groove in the top half of each bearing transfers oil into the crankshaft for lubrication of the connecting rod bearings. A lead/bronze thrust washer is installed each side of the top half of the center main bearing. The crankshaft rear oil seal (a lip seal similar to that used on the AJ16 engine) is a press fit in the bedplate to cylinder block interface.

SEALANT TRACK ON BEDPLATE

303-012

CRANKSHAFT REAR OIL SEAL

303-013

Engine AJ-V8/5HP24

Connecting Rods and Pistons

The connecting rods are manufactured in sinter forged steel. The bearing caps are produced by fracturing the opposing sides of the connecting rod at the bearing horizontal center-line. As well as being easier to manufacture, when re-assembled the fractured surfaces interlock to form a strong seamless joint. The cylinder position is etched on adjoining sides of the joint to identify matching connecting rods and bearing caps. The connecting rod bearings are lead/bronze split plain bearings. The pistons are of the open ended skirt design with flat upper surfaces to reduce heat absorbtion. Three piston rings, two compression and one oil control, are installed on each piston. Each piston is installed on a wrist pin located in a lead/bronze bushing in the connecting rod.

Sump

The sump consists of an aluminum alloy structural sump bolted to the bedplate, and a pressed steel oil pan bolted to the structural sump. A windage tray attached to the top of the structural sump isolates the oil pan from the disturbed air produced by the rotation of the crankshaft, to prevent oil aeration and improve oil drainage. A rubber plug at the rear of the structural sump seals the port that provides access to the torque converter securing bolts. The engine oil drain plug is located at the front right corner of the oil pan. A silicon rubber in-groove gasket seals the joint between the oil pan and the structural sump; a bead of sealant seals the joint between the structural sump and the bedplate.

CONNECTING ROD AND PISTON

303-014

SEALANT TRACK ON STRUCTURAL SUMP

303-021

EngineAJ-V8/5HP24

Starter and Drive Plate

The engine starter motor is installed at the rear right side of the engine, at the cylinder block to bedplate split line (for further details of the starter motor see Technical Guide, XK8 Introduction). The starter drive plate is attached to the rear of the crankshaft. A timing disc, for the engine speed sensor, is spot welded to the front face of the drive plate.

STRUCTURAL SUMP AND OIL PAN

STARTER MOTOR

303-062

Torque Converter Access

303-010

Engine AJ-V8/5HP24

Cylinder Heads

The cylinder heads are unique to each cylinder bank. Deep seated bolts, to reduce distortion, secure the cylinder heads to the cylinder block. Two hollow dowels align each cylinder head with the cylinder block. The cylinder head gaskets consist of a silicon beaded composite gasket with metal eyelets for the cylinder bores, similar to that on the AJ16 engine. Each cylinder head incorporates dual overhead camshafts operating four valves per cylinder via solid aluminum alloy valve lifters. Steel shims in the top of the valve lifters enable adjustment of valve clearances. 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. The camshafts are manufactured in chilled cast iron. Five aluminum 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. The rear of B bank intake camshaft has a timing ring for the camshaft position sensor. A flat, machined near the front of each camshaft, enables the camshafts to be locked during the valve timing procedure.

CAMSHAFT POSITION SENSOR TIMING RING

303-054

The 14 mm spark plugs, one per cylinder, locate in recesses down the center-line of each cylinder head. An engine lifting eye is cast into the front of each cylinder head (the rear lifting eyes, one on each cylinder head, are bolt-on tools).

TIMING DISC

STARTER DRIVE PLATE

303-035

303-034

EngineAJ-V8/5HP24

Timing Gear

Single row primary and secondary chains drive the camshafts of each cylinder bank. The primary chains transmit the drive from two sprockets on the crankshaft to variable valve timing units on the intake camshafts. The secondary chains transmit the drive from the variable valve timing units to sprockets on the exhaust camshafts.

A BANK CYLINDER HEAD

303-047

Lifting Eye

Intake Camshaft

Exhaust Camshaft

(Continued on Page 14)

Engine AJ-V8/5HP24

303-016 / 017

Primary Chain Tensioner

Secondary Chain Tensioner

Secondary Chain

Variable Valve Timing Unit

Primary Chain

TIMING GEAR

EngineAJ-V8/5HP24

A key locates the two drive sprockets on the crankshaft. The crankshaft's torsional vibration damper retains the sprockets in position. The variable valve timing units and the exhaust camshaft sprockets are non-interference, nonkeyed fits on their respective camshafts; the drive being transmitted by the face to face friction load produced by the valve timing unit/sprocket securing bolt. Each chain has an hydraulic tensioner operated by engine oil. A jet of oil from the end of each tensioner lubricates the chains. The primary chain tensioners act on pivoting flexible tensioner blades. The secondary chain tensioners act directly on the chains. Guide rails are installed on the drive side of the primary chains.

Timing Cover

The aluminum alloy timing cover accommodates the crankshaft front oil seal (a PTFE lip seal) and the two variable valve timing solenoids. Silicon rubber in-groove gaskets seal the joint between the timing cover and the front face of the engine.

TIMING COVER

Crankshaft Front Oil Seal

303-015

Timing Gear (Continued)

Variable Valve Timing Solenoid

Engine AJ-V8/5HP24

Camshaft Covers

The camshaft covers are manufactured from vinyl ester composite. The A bank camshaft cover incorporates an outlet for the full load engine breather. The B bank camshaft cover incorporates the engine oil filler cap and an outlet for the part load engine breather. Identical oil separators are incorporated below the breather outlet in each cover (see Crankcase Ventilation, page 35). Silicon rubber in-groove gaskets seal the joints between the camshaft covers and the cylinder heads. Together with spacers and seals on the camshaft cover fasteners, they also isolate the covers from direct contact with the cylinder heads, to reduce noise.

B BANK CAMSHAFT COVER

303-042

EngineAJ-V8/5HP24

Exhaust Manifold

The thin-wall cast iron manifolds are unique for each cylinder bank. On engines with EGR, the A bank manifold has a connection for the 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.

EXHAUST MANIFOLD

303-023

Engine AJ-V8/5HP24

Engine Cooling

The cooling system is a low volume, high velocity system with good warm-up and temperature profile characteristics. From the pump, the coolant flows into each bank of the cylinder block. In each bank, 50% of the coolant cools the cylinder bores and 50% is diverted through a bypass gallery. At the rear of the banks the two flows mix and enter the cylinder heads. The coolant then flows forwards to the outlet ports. When the thermostat is closed, the coolant returns directly to the pump through the bypass on the thermostat housing. When the thermostat is open, the coolant returns to the pump via the vehicle's radiator. A coolant drain plug is installed on the rear left side of the cylinder block. On vehicles with the cold climate package, the cylinder block heater replaces the drain plug.

Note: Coolant is drained from the right bank of

the cylinder block by removing the coolant pipe behind the starter motor.

CYLINDER BLOCK DRAIN/HEATER

COOLING SYSTEM DIAGRAM

1. Electronic Throttle

2. EGR Valve

3. A/C Heater Return

4. Coolant Pump

5. Thermostat Housing

6. Vehicle Radiator (Reference)

7. A/C Heater Supply

8. Bleed Outlet

303-O63

303-028

EngineAJ-V8/5HP24

Coolant Pump

The coolant pump is installed between the two cylinder banks, on the front face of the cylinder block. The pumping element is a shrouded composite impeller. Coolant escapes from seal breather holes in the housing if the pump's bearing seal fails. An O-ring and an edge bonded rubber/aluminum alloy gasket seal the pump to cylinder block interface. The O-ring seals the inlet port from the thermostat. The gasket seals the outlet ports into the cylinder banks.

Thermostat Housing

The composite thermostat housing is installed between the two cylinder banks, immediately above the coolant pump. The thermostat controls the flow of coolant through the radiator. It starts to open at 80 to 84°C (176 to 183˚F) and is fully open at 96°C (205˚F). A duct in the cylinder block connects the thermostat housing outlet to the pump inlet. A stub pipe connects the duct to the air conditioning heater matrix return line. An in-groove gasket seals the joint between the thermostat housing and the cylinder block. In addition to containing the thermostat, the composite thermostat housing incorporates connections for the bleed, bypass and radiator bottom hoses. The bleed outlet vents any air in the system into the vehicle's coolant reservoir. The cap of the thermostat housing is removable, to allow air out of the system when filling from empty.

CAUTION: Use the correct torque (marked on

the cap) when re-installing the cap, or the cap/thermostat housing could be damaged.

COOLANT PUMP

303-030

THERMOSTAT HOUSING

Coolant Hoses

Supply and return hoses for the air conditioning heater matrix are installed between the cylinder banks. A connection at the rear of A bank provides the coolant supply for the electronic throttle and the EGR valve. The outlet from the EGR valve connects to the return hose of the air conditioning heater matrix.

By-pass

From Radiator

A/C Heater Return

Cap

Bleed

303-029

Engine AJ-V8/5HP24

COOLANT HOSES

A/C Heater Matrix

303-032

Electronic Throttle

EGR Valve

Electronic Throttle

EngineAJ-V8/5HP24

Engine Lubrication

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 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 B bank camshaft cover. With the exception of the pump and level gauge, all oil system components are installed on the structural sump.

Coolant Outlet Duct

The composite coolant outlet duct connects to the outlet port of each cylinder head to provide a common connection point for the radiator top hose. It also incorporates connections for the coolant temperature sensor, the supply to the air conditioning heater matrix, and the bypass flow to the thermostat housing. An in-groove gasket seals each of the joints between the outlet duct and the cylinder heads.

COOLANT OUTLET DUCT

ECT Sensor

A/C Heater Supply

By-pass

To Radiator

303-066

Engine AJ-V8/5HP24

LUBRICATION SYSTEM

1. Valve Lifter Supply

2. Main Bearing Supply

3. Connecting Rod Bearing Supply

4. Bedplate/Cylinder Block Interface

5. Oil Pick-up

6. Pressure Relief Valve

7. Oil Pressure Switch

8. Oil Filter

9. Structural Sump/Bedplate Interface

10. Bedplate/Cylinder Block Interface

11. Oil Pump

12. Primary Chain Tensioner Supply

13. Cylinder Block/Cylinder Head Interface

14. Variable Valve Timing Supply

15. Camshaft Bearing Supply

16. Secondary Chain Tensioner Supply

303-007

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