1997 JAGUAR XJ6 EGR

3261 Jaguar XJ6
1
Chapter 1
Routine maintenance and servicing
Air cleaner element renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Automatic transmission fluid and filter renewal . . . . . . . . . . . . . . . . . 26
Automatic transmission fluid level check . . . . . . . . . . . . . . . . . . . . . 8
Battery check and general information . . . . . . . . . . . . . . . . . . . . . . . 6
Brake fluid renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Braking system - general check and adjustment . . . . . . . . . . . . . . . 11
Coolant renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Crankcase ventilation system check . . . . . . . . . . . . . . . . . . . . . . . . . 20
Differential oil level check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Differential oil renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Drivebelt check and renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Engine oil and filter renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Exhaust system check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Front wheel alignment check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Front wheel bearing check and adjustment . . . . . . . . . . . . . . . . . . . 22Fuel filter renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
General information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
General lubrication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Handbrake shoes check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Headlight beam check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Hose and fluid leak check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Ignition system check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Intensive maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Power hydraulic system fluid level check . . . . . . . . . . . . . . . . . . . . . 5
Propshaft check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Road test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Seat belt check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Spark plug check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Spark plug renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Steering and suspension check . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
1•1
Contents
Easy,suitable for
novice with little
experienceFairly easy,suitable
for beginner with
some experienceFairly difficult,
suitable for competent
DIY mechanic
Difficult,suitable for
experienced DIY
mechanicVery difficult,
suitable for expert DIY
or professional
Degrees of difficulty
54321

3261 Jaguar XJ6
2A
Chapter 2 Part A
Engine in-car repair procedures
General
Cylinder numbers (front to rear) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2-3-4-5-6
Firing order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5-3-6-2-4
Displacement:
3.2 litre engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3239 cc
3.6 litre engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3590 cc
4.0 litre engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3980 cc
Bore . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91.0 mm (3.583 inches)
Stroke:
3.2 litre engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83.0 mm (3.268 inches)
3.6 litre engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92.0 mm (3.622 inches)
4.0 litre engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102.0 mm (4.016 inches)
Camshafts and lifters
Journal diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26.9370 to 26.9494 mm (1.0605 to 1.0610 inches)
Bearing oil clearance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.037 to 0.063 mm (0.0014 to 0.0024 inch)
Runout limit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.0406 mm (0.0016 inch)
Lobe lift (maximum variation between lobes) . . . . . . . . . . . . . . . . . . . . . 0.0127 mm (0.005 inch)
Valve lifter
Diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33.34 to 33.35 mm (1.3126 to 1.3130 inches)
Oil clearance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.020 to 0.050 mm (0.0008 to 0.0020 inch)
Valve clearances . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.30 to 0.36 mm (0.012 to 0.014 inch)
Oil pump
Outer rotor to body clearance, maximum . . . . . . . . . . . . . . . . . . . . . . . 0.2 mm (0.0079 inch)
Outer rotor OD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69.774 to 69.825 mm (2.7470 to 2.7490 inches)
Rotor thickness, inner and outer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27.962 to 27.975 mm (1.1008 to 1.1013 inches)
Clearance over rotors, maximum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.1 mm (0.0039 inch) Auxiliary shaft - renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Camshafts and lifters - removal, inspection and refitting . . . . . . . . . 10
CHECK ENGINE light . . . . . . . . . . . . . . . . . . . . . . . . . . . See Chapter 6
Crankshaft front oil seal - renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Crankshaft rear oil seal - renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Cylinder compression check . . . . . . . . . . . . . . . . . . . . See Chapter 2B
Cylinder head - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . 11
Drivebelt check, adjustment and renewal . . . . . . . . . . . See Chapter 1
Driveplate - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Engine mounts - check and renewal . . . . . . . . . . . . . . . . . . . . . . . . . 16
Engine oil and filter change . . . . . . . . . . . . . . . . . . . . . . See Chapter 1
Engine overhaul - general information . . . . . . . . . . . . . See Chapter 2B
Engine - removal and refitting . . . . . . . . . . . . . . . . . . . See Chapter 2BExhaust manifolds - removal and refitting . . . . . . . . . . . . . . . . . . . . . 6
General information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Intake manifold - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . 5
Sump - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Oil pump - removal, inspection and refitting . . . . . . . . . . . . . . . . . . . 13
Repair operations possible with the engine in the vehicle . . . . . . . . 2
Spark plug renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . See Chapter 1
Timing chains and sprockets - removal, inspection and refitting . . . 8
Top Dead Centre (TDC) for number one piston - locating . . . . . . . . . 3
Valve cover - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Valves - servicing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . See Chapter 2B
Water pump - removal and refitting . . . . . . . . . . . . . . . . See Chapter 3
2A•1
Specifications Contents
Easy,suitable for
novice with little
experienceFairly easy,suitable
for beginner with
some experienceFairly difficult,
suitable for competent
DIY mechanic
Difficult,suitable for
experienced DIY
mechanicVery difficult,
suitable for expert DIY
or professional
Degrees of difficulty
54321

Torque wrench settings*Nm lbf ft
Camshaft bearing cap bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 to 27 16 to 20
Camshaft sprocket bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 to 27 16 to 20
Crankshaft damper-to-crankshaft bolt
3.2 and 3.6 litre . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204 151
4.0 litre . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 180 to 220 133 to 162
Crankshaft pulley to damper bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 to 27 16 to 20
Crankshaft rear oil seal retainer bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 to 27 16 to 20
Crankshaft sensor bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 to 27 16 to 20
Cylinder head bolts
Step 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60 44
Step 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Tighten an additional 90° (1/4 turn)
Driveplate bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123 to 149 91 to 110
Engine mounts
To engine block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 to 66 36 to 39
To chassis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 to 24 16 to 18
Exhaust manifold heat shield fasteners . . . . . . . . . . . . . . . . . . . . . . . . . 23 to 27 16 to 20
Exhaust manifold nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 to 27 16 to 20
Intake manifold nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 to 27 16 to 20
Oil pump bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 to 27 16 to 20
Sump bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 to 27 16 to 20
Sump bolts, adapter to pan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 to 54 36 to 40
Timing chain cover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 to 27 16 to 20
Valve cover screws . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 to 12 7 to 9
*Note:Refer to Part B for additional specifications
2A•2 Engine in-car repair procedures
3261 Jaguar XJ6
1 General information
This Part of Chapter 2 is devoted to in-car
repair procedures for the in-line six-cylinder
engines. All information concerning engine
removal and refitting and engine block and
cylinder head overhaul can be found in Part B
of this Chapter.
The following repair procedures are based
on the assumption that the engine is installed
in the car. If the engine has been removed
from the car and mounted on a stand, many of
the steps outlined in this Part of Chapter 2 will
not apply. We have photographed some in-
car engine procedures with the engine on a
stand for photographic purposes.
The Specifications included in this Part of
Chapter 2 apply only to the procedures
contained in this Part. Part B of Chapter 2
includes the Specifications necessary for
cylinder head and engine block rebuilding.
2 Repair operations possible
with the engine in the car
Many repair operations can be
accomplished without removing the engine
from the car.
Clean the engine compartment and the
exterior of the engine with some type of
degreaser before any work is done. It will
make the job easier and help keep dirt out of
the internal areas of the engine.
Depending on the components involved, itmay be helpful to remove the bonnet to
improve access to the engine as repairs are
performed (refer to Chapter 11 if necessary).
Cover the wings to prevent damage to the
paint. Special pads are available, but an old
bedspread or blanket will also work.
If vacuum, exhaust, oil or coolant leaks
develop, indicating a need for gasket or seal
renewal, the repairs can generally be made
with the engine in the car. The intake and
exhaust manifold gaskets, crankshaft oil seals
and cylinder head gasket are all accessible
with the engine in place (although rear oil seal
renewal involves removal of the transmission).
The sump is difficult for a home mechanic to
replace without a hoist and other specialised
equipment, since the front suspension,
steering and crossmember must be lowered
to allow enough clearance for sump removal.
If such equipment is not available, the
alternative would be to remove the engine for
renewal of the sump or oil pump. Note:We
assume that the home mechanic does not
have access to the specialised equipment,
and have photographed our subject engine
out of the car for some procedures.
Exterior engine components, such as the
intake and exhaust manifolds, the water
pump, the starter motor, the alternator, the
distributor and the fuel system components
can be removed for repair with the engine in
place.
Since the cylinder head can be removed
with the engine in-car, camshaft and valve
component servicing can also be
accomplished. Renewal of the timing chains
and sprockets is also possible with the engine
in-car.
3 Top Dead Centre (TDC) for
number one piston- locating
1
Note:The following procedure is based on the
assumption that the distributor is correctly
installed. If you are trying to locate TDC to refit
the distributor correctly, piston position must
be determined by feeling for compression at
the number one spark plug hole, then aligning
the ignition timing marks (see paragraph 8).
1Top Dead Centre (TDC) is the highest point
in the cylinder that each piston reaches as it
travels up the cylinder bore. Each piston
reaches TDC on the compression stroke and
again on the exhaust stroke, but TDC
generally refers to piston position on the
compression stroke.
2Positioning the piston(s) at TDC is an
essential part of many procedures such as
camshaft and timing chain/sprocket removal
and distributor removal.
3Before beginning this procedure, be sure to
place the transmission in Neutral and apply
the handbrake or block the rear wheels. Also,
disable the ignition system by detaching the
coil wire from the centre terminal of the
distributor cap and grounding it on the engine
block with a jumper wire. Remove the spark
plugs (see Chapter 1).
4In order to bring any piston to TDC, the
crankshaft must be turned using one of the
methods outlined below. When looking at the
timing chain end of the engine, normal
crankshaft rotation is clockwise.
a) The preferred method is to turn the
crankshaft with a socket and ratchet

8Tighten the screws to the torque listed in
this Chapter’s Specifications in three or four
equal steps.
9Refit the remaining components, start the
engine and check for oil leaks.
5 Intake manifold-
removal and refitting
2
Removal
1Disconnect the negative cable from the
battery.
Caution: If the stereo in your vehicle is
equipped with an anti-theft system, make
sure you have the correct activation code
before disconnecting the battery.
2Refer to Chapter 4 to remove the
accelerator and cruise-control linkage, safely
relieve the fuel system pressure, and
disconnect the fuel supply lines.
3Label or mark and detach the PCV and
vacuum hoses connected to the intake
manifold, (see illustration).
4The intake manifold can be removed with
the injectors and fuel rail still in place.
Disconnect the electrical connectors at
each injector (label them first for reassembly).
If the injectors are to be removed from the
intake manifold, refer to Chapter 4.
5Refer to Chapter 4 and remove the throttle
body.6Remove the three nuts retaining the oil filler
tube bracket, then pull the tube up as far as
possible (see illustrations).
7Remove the ground strap and intake
manifold mounting nuts/bolts, then detach the
intake manifold from the engine (see
illustrations).
Refitting
8Clean the mating surfaces of the intake
manifold and the cylinder head mounting
surface with lacquer thinner or acetone. If the
gasket shows signs of leaking, have the
manifold checked for warpage at an
automotive machine workshop and
resurfaced if necessary.
9Refit a new gasket, then position the intake
manifold on the cylinder head and refit the
nuts/bolts (see illustration).
10Tighten the nuts/bolts in three or four
equal steps to the torque listed in this
Chapter’s Specifications. Work from the
centre out towards the ends to avoid warping
the manifold.
11Refit the remaining parts in the reverse
order of removal.
12Before starting the engine, check the
throttle linkage for smooth operation.
13Run the engine and check for coolant and
vacuum leaks.
14Road test the car and check for proper
operation of all accessories, including the
cruise control system.
6 Exhaust manifolds-
removal and refitting
2
Warning: The engine must be
completely cool before beginning
this procedure.
Removal
1Disconnect the negative cable from the
battery.
Caution: If the stereo in your vehicle is
equipped with an anti-theft system, make
sure you have the correct activation code
before disconnecting the battery.
2On 1990 and later models, disconnect the
EGR pipe and remove the EGR valve from the
top of the exhaust manifold (see Chapter 6).
3Apply penetrating oil to the exhaust
manifold mounting nuts/bolts, and the nuts
retaining the exhaust pipes to the manifolds.
After the nuts have soaked, remove the nuts
retaining the exhaust pipes to the manifolds
and the lower bolt from the heat shield (see
illustration).
4Remove the heat shield from the exhaust
manifolds(see illustration).
5Disconnect the electrical connector to the
oxygen sensor. Unless the oxygen sensor is
being renewed, leave the sensor in place.
6Remove the nuts/bolts and detach the
manifolds and gaskets (see illustration).
2A•4 Engine in-car repair procedures
5.3 The various hoses should be marked
to ensure correct refitting5.6a Remove the oil filler tube bracket
nuts (arrowed) . . .5.6b . . . pull the tube up to dislodge it
from the housing - it won’t come out, but
can be removed with the intake manifold
5.7a Remove the ground strap from the
front stud (arrowed), and the engine wiring
harness clips from the other studs5.7b Remove the intake manifold bolts/
nuts and remove the intake manifold - the
upper fasteners are studs/nuts, while the
lower row are bolts (two arrowed)5.9 Refit the new intake manifold gasket
over the studs (arrowed) refit the manifold
3261 Jaguar XJ6

3261 Jaguar XJ6
2B
Chapter 2 Part B
Engine removal and overhaul procedures
General
Cylinder compression pressure @ 300 rpm, warm
Standard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.6 to 11.3 bar (150 to 160 psi)
High compression models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11.3 to 12.1 bar (160 to 170 psi)
Maximum variation between cylinders . . . . . . . . . . . . . . . . . . . . . . . . 0.8 bar (10 psi)
Oil pressure (engine warm)
At idle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.1 bar (30 psi) minimum
At 4000 rpm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.9 bar (70 psi) minimum
Cylinder head
Resurfacing limit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.25 mm (0.010 inch) maximum
Minimum thickness (see text)
3.6 litre . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129.6 mm (5.101 inches)
3.2 and 4.0 litre . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129.7 mm (5.108 inches)
Valves and related components
Valve stem-to-guide clearance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.038 to 0.076 mm (0.0015 to 0.0030 inch)
Valve springs, free length . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40.13 mm (1.580 inches)
Valve lifter
Diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33.34 to 33.35 mm (1.3126 to 1.3130 inches)
Lifter-to-bore clearance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.02 to 0.05 mm (0.0008 to 0.0020 inch)
Crankshaft and connecting rods
Connecting rod journal
Diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52.97 to 52.99 mm (2.0856 to 2.0861 inches)
Taper and out-of-round limits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.008 mm (0.0003 inch) maximum
Bearing oil clearance
3.6 litre . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.040 to 0.083 mm (0.0016 to 0.0033 inch)
3.2 and 4.0 litre . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.025 to 0.0068 mm (0.0010 to 0.0027 inch)
Connecting rod side clearance (endplay) . . . . . . . . . . . . . . . . . . . . . . . . 0.127 to 0.228 mm (0.005 to 0.009 inch)
Main bearing journal
Diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76.217 to 76.233 mm (3.0007 to 3.0012 inches)
Taper and out-of-round limits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.008 mm (0.0003 inch) maximum
Bearing oil clearance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.040 to 0.083 mm (0.0016 to 0.0033 inch)
Crankshaft endplay (standard) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.101 to 0.254 mm (0.004 to 0.010 inch) CHECK ENGINE light . . . . . . . . . . . . . . . . . . . . . . . . . . . See Chapter 6
Crankshaft - inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Crankshaft - refitting and main bearing oil clearance check . . . . . . . 23
Crankshaft - removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Cylinder head - cleaning and inspection . . . . . . . . . . . . . . . . . . . . . . 10
Cylinder head - dismantling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Cylinder head - reassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Cylinder compression check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Cylinder honing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Engine block - cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Engine block - inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Engine overhaul - dismantling sequence . . . . . . . . . . . . . . . . . . . . . . 8
Engine overhaul - general information . . . . . . . . . . . . . . . . . . . . . . . . 2
Engine overhaul - reassembly sequence . . . . . . . . . . . . . . . . . . . . . . 21Engine rebuilding alternatives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Engine - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Engine removal - methods and precautions . . . . . . . . . . . . . . . . . . . 5
General information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Initial start-up and running-in after overhaul . . . . . . . . . . . . . . . . . . . 26
Main and connecting big-end bearings - inspection and selection . 20
Pistons/connecting rods - inspection . . . . . . . . . . . . . . . . . . . . . . . . 18
Pistons/connecting rods - refitting and big-end bearing
oil clearance check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Pistons/connecting rods - removal . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Piston rings - refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Rear main oil seal refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Vacuum gauge diagnostic checks . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Valves - servicing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
2B•1
Specifications Contents
Easy,suitable for
novice with little
experienceFairly easy,suitable
for beginner with
some experienceFairly difficult,
suitable for competent
DIY mechanic
Difficult,suitable for
experienced DIY
mechanicVery difficult,
suitable for expert DIY
or professional
Degrees of difficulty
54321

Engine block
Deck warpage limit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.076 mm (0.003 inch)
Cylinder bore diameter
Standard
Size group A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90.990 to 91.003 mm (3.5823 to 3.5828 inches)
Size group B . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91.005 to 91.018 mm (3.5829 to 3.5834 inches)
Oversize
0.25 mm (0.010 inch) OS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91.259 to 91.272 mm (3.5929 to 3.5934 inches)
0.50 mm (0.020 inch) OS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91.513 to 91.526 mm (3.6029 to 3.6034 inches)
Pistons and rings
Piston-to-bore clearance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.017 to 0.043 mm (0.0007 to 0.0017 inch)
Piston ring end gap
No.1 (top) compression ring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.40 to 0.66 mm (0.016 to 0.026 inch)
No.2 (middle) compression ring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.40 to 0.66 mm (0.016 to 0.026 inch)
Oil ring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.30 to 0.55 mm (0.012 to 0.022 inch)
Piston ring groove clearance
No. 1 (top) compression ring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.040 to 0.076 mm (0.0016 to 0.0030 inch)
No. 2 (middle) compression ring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.040 to 0.076 mm (0.0016 to 0.0030 inch)
Torque wrench settingsNm lbf ft
Main bearing cap bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136 to 142 100 to 105
Connecting rod cap nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 to 60 37 to 44
* Note:Refer to Part A for additional torque specifications.
2B•2 Engine removal and overhaul procedures
3261 Jaguar XJ6
1 General information
Included in this portion of Chapter 2 are the
general overhaul procedures for the cylinder
head and internal engine components.
The information ranges from advice
concerning preparation for an overhaul and
the purchase of replacement parts to detailed,
step-by-step procedures covering removal
and refitting of internal engine components
and the inspection of parts.
The following Sections have been written
based on the assumption that the engine has
been removed from the vehicle. For
information concerning in-vehicle engine
repair, as well as removal and refitting of the
external components necessary for the
overhaul, see Part A of this Chapter.
The Specifications included in this Part are
only those necessary for the inspection and
overhaul procedures which follow. Refer to
Part A for additional Specifications.
2 Engine overhaul-
general information
It’s not always easy to determine when, or if,
an engine should be completely overhauled,
as a number of factors must be considered.
High mileage is not necessarily an indication
that an overhaul is needed, while low mileage
doesn’t preclude the need for an overhaul.
Frequency of servicing is probably the most
important consideration. An engine that’s had
regular and frequent oil and filter changes, as
well as other required maintenance, will most
likely give many thousands of miles of reliableservice. Conversely, a neglected engine may
require an overhaul very early in its life.
Excessive oil consumption is an indication
that piston rings, valve seals and/or valve
guides are in need of attention. Make sure that
oil leaks aren’t responsible before deciding
that the rings and/or guides are bad. Perform a
cylinder compression check to determine the
extent of the work required (see Section 4).
Also check the vacuum readings under various
conditions (see Section 3).
Check the oil pressure with a gauge
installed in place of the oil pressure sender
unit (see illustrations)and compare it to this
Chapter’s Specifications. If it’s extremely low,
the bearings and/or oil pump are probably
worn out.
Loss of power, rough running, knocking or
metallic engine noises, excessive valve train
noise and high fuel consumption rates may
also point to the need for an overhaul,
especially if they’re all present at the same
time. If a complete tune-up doesn’t remedy
the situation, major mechanical work is the
only solution.An engine overhaul involves restoring the
internal parts to the specifications of a new
engine. During an overhaul, the piston rings
are replaced and the cylinder walls are
reconditioned (rebored and/or honed). If a
rebore is done by an automotive machine
workshop, new oversize pistons will also be
installed. The main bearings, big-end bearings
and camshaft bearings are generally replaced
with new ones and, if necessary, the
crankshaft may be reground to restore the
journals. Generally, the valves are serviced as
well, since they’re usually in less-than-perfect
condition at this point. While the engine is
being overhauled, other components, such as
the distributor, starter and alternator, can be
rebuilt as well. The end result should be a like
new engine that will give many trouble free
miles. Note:Critical cooling system
components such as the hoses, drivebelts,
thermostat and water pump should be
replaced with new parts when an engine is
overhauled. The radiator should be checked
carefully to ensure that it isn’t clogged or
leaking (see Chapter 3).If you purchase a
2.4a The oil pressure sender unit (arrowed)
is located in the right front corner of the
engine block, near the oil filter2.4b The oil pressure can be checked by
removing the sender unit and refitting a
pressure gauge in its place

in the back sides of the ring grooves and the
oil hole in the lower end of each rod are clear.
6If the pistons and cylinder walls aren’t
damaged or worn excessively, and if the
engine block is not rebored, new pistons
won’t be necessary. Normal piston wear
appears as even vertical wear on the piston
thrust surfaces and slight looseness of the top
ring in its groove. New piston rings, however,
should always be used when an engine is
rebuilt.
7Carefully inspect each piston for cracks
around the skirt, at the pin bosses and at the
ring lands.
Caution: Some early 1988 3.6 litre engines
(before engine no. 9D 121113) have
incorrectly-stamped pistons. On these, the
word FRONT is actually stamped on the rear
of the pistons. Correct pistons will have the
cast arrows on the inside of the skirt to your
left when facing the word FRONT.
8Look for scoring and scuffing on the thrust
faces of the skirt, holes in the piston crown
and burned areas at the edge of the crown. If
the skirt is scored or scuffed, the engine may
have been suffering from overheating and/or
abnormal combustion, which caused
excessively high operating temperatures. The
cooling and lubrication systems should be
checked thoroughly. A hole in the piston
crown is an indication that abnormal
combustion (pre-ignition) was occurring.
Burned areas at the edge of the piston crown
are usually evidence of spark knock
(detonation). If any of the above problems
exist, the causes must be corrected or the
damage will occur again. The causes may
include intake air leaks, incorrect air/fuel
mixture, incorrect ignition timing and EGR
system malfunctions.
9Corrosion of the piston, in the form of small
pits, indicates that coolant is leaking into the
combustion chamber and/or the crankcase.
Again, the cause must be corrected or the
problem may persist in the rebuilt engine.
10Measure the piston ring groove clearance
by laying a new piston ring in each ring groove
and slipping a feeler gauge in beside it (see
illustration). Check the clearance at three or
four locations around each groove. Be sure touse the correct ring for each groove - they are
different. If the clearance is greater than that
listed in this Chapter’s Specifications, new
pistons will have to be used.
11Check the piston-to-bore clearance by
measuring the bore (see Section 16) and the
piston diameter. Make sure the pistons and
bores are correctly matched. Measure the
piston across the skirt, at a 90° angle to
the piston pin (see illustration). Subtract the
piston diameter from the bore diameter to
obtain the clearance. If it’s greater than
specified, the engine block will have to be
rebored and new pistons and rings installed.
12Check the piston-to-rod clearance by
twisting the piston and rod in opposite
directions. Any noticeable play indicates
excessive wear, which must be corrected.
13If the pistons must be removed from the
connecting rods for any reason, the rods
should be taken to an automotive machine
workshop, to be checked for bend and twist,
since automotive machine shops have special
equipment for this purpose.
14Check the connecting rods for cracks and
other damage. Temporarily remove the rod
caps, lift out the old bearing inserts, wipe the
connecting rod and cap bearing surfaces
clean and inspect them for nicks, gouges and
scratches. After checking the connecting
rods, renew the old bearings, slip the caps
into place and tighten the nuts finger tight.
Note:If the engine is being rebuilt because of
a connecting rod knock, be sure to refit new
rods.
19 Crankshaft- inspection
3
1Clean the crankshaft with solvent and dry it
with compressed air (if available). Be sure to
clean the oil holes with a stiff brush and flush
them with solvent.
2Check the main and connecting rod bearing
journals for uneven wear, scoring, pits and
cracks.
3Remove all burrs from the crankshaft oil
holes with a stone, file or scraper.4Check the remainder of the crankshaft for
cracks and other damage. It should be
magnafluxed to reveal hidden cracks - an
automotive machine workshop will handle the
procedure.
5Using a micrometer, measure the diameter
of the main and connecting rod journals and
compare the results to this Chapter’s
Specifications (see illustration). By
measuring the diameter at a number of points
around each journal’s circumference, you’ll be
able to determine whether or not the journal is
out-of-round. Take the measurement at each
end of the journal, near the crank throws, to
determine if the journal is tapered. Crankshaft
runout should be checked also, but large V-
blocks and a dial indicator are needed to do it
correctly. If you don’t have the equipment,
have a machine workshop check the runout.
6If the crankshaft journals are damaged,
tapered, out-of-round or worn beyond the
limits given in the Specifications, have the
crankshaft reground by an automotive
machine workshop. Be sure to use the correct
size bearing inserts if the crankshaft is
reconditioned.
7Check the oil seal journals at each end of
the crankshaft for wear and damage. If the
seal has worn a groove in the journal, or if it’s
nicked or scratched, the new seal may leak
when the engine is reassembled. In some
cases, an automotive machine workshop may
be able to repair the journal by pressing on a
thin sleeve. If repair isn’t feasible, a new or
different crankshaft should be installed.
8Refer to Section 20 and examine the main
and big-end bearing inserts.
20 Main and big-end bearings-
inspection and selection
3
Inspection
1Even though the main and big-end bearings
should be replaced with new ones during the
engine overhaul, the old bearings should be
retained for close examination, as they may
Engine removal and overhaul procedures 2B•13
2B
19.5 Measure the diameter of each
crankshaft journal at several points to
detect taper and out-of-round conditions
3261 Jaguar XJ6 18.10 Check the ring groove clearance
with a feeler gauge at several points
around the groove
18.11 Measure the piston diameter at a
90° angle to the piston pin, at the bottom
of the piston pin area - a precision caliper
may be used if a micrometer isn’t available

reveal valuable information about the condition
of the engine (see illustration).
2Bearing failure occurs because of lack of
lubrication, the presence of dirt or other foreign
particles, overloading the engine and corrosion.
Regardless of the cause of failure, it must be
corrected before the engine is reassembled to
prevent it from happening again.
3When examining the bearings, remove
them from the engine block, the main bearing
caps, the connecting rods and the rod caps
and lay them out on a clean surface in the
same general position as their location in the
engine. This will enable you to match any
bearing problems with the corresponding
crankshaft journal.
4Dirt and other foreign particles get into the
engine in a variety of ways. It may be left in
the engine during assembly, or it may pass
through filters or the PCV system. It may get
into the oil, and from there into the bearings.
Metal chips from machining operations and
normal engine wear are often present.
Abrasives are sometimes left in engine
components after reconditioning, especially
when parts are not thoroughly cleaned using
the proper cleaning methods. Whatever the
source, these foreign objects often end up
embedded in the soft bearing material and are
easily recognised. Large particles will not
embed in the bearing and will score or gouge
the bearing and journal. The best prevention
for this cause of bearing failure is to clean all
parts thoroughly and keep everything
spotlessly clean during engine assembly.
Frequent and regular engine oil and filter
changes are also recommended.5Lack of lubrication (or lubrication
breakdown) has a number of interrelated
causes. Excessive heat (which thins the oil),
overloading (which squeezes the oil from the
bearing face) and oil leakage or throw off
(from excessive bearing clearances, worn oil
pump or high engine speeds) all contribute to
lubrication breakdown. Blocked oil passages,
which usually are the result of misaligned oil
holes in a bearing shell, will also oil starve a
bearing and destroy it. When lack of
lubrication is the cause of bearing failure, the
bearing material is wiped or extruded from the
steel backing of the bearing. Temperatures
may increase to the point where the steel
backing turns blue from overheating.
6Driving habits can have a definite effect on
bearing life. Low speed operation in too high a
gear (labouring the engine) puts extremely
high loads on bearings, which tends to
squeeze out the oil film. These loads cause
the bearings to flex, which produces fine
cracks in the bearing face (fatigue failure).
Eventually the bearing material will loosen in
pieces and tear away from the steel backing.
Short trip driving leads to corrosion of
bearings because insufficient engine heat is
produced to drive off the condensed water
and corrosive gases. These products collect
in the engine oil, forming acid and sludge. As
the oil is carried to the engine bearings, the
acid attacks and corrodes the bearing
material.
7Incorrect bearing refitting during engine
assembly will lead to bearing failure as well.
Tight-fitting bearings leave insufficient bearing
oil clearance, and this will lead to oilstarvation. Dirt or foreign particles trapped
behind a bearing insert result in high spots on
the bearing which lead to failure.
Selection
8If the original bearings are worn or
damaged, or if the oil clearances are incorrect
(see Sections 23 or 25), the following
procedures should be used to select the
correct new bearings for engine reassembly.
However, if the crankshaft has been reground,
new undersize bearings must be installed -
the following procedure should not be used if
undersize bearings are required! The
automotive machine workshop that
reconditions the crankshaft will provide or
help you select the correct-size bearings.
Regardless of how the bearing sizes are
determined, use the oil clearance, measured
with Plastigage, as a guide to ensure the
bearings are the right size.
9If you need to use a STANDARD size main
or big-end bearing, refit one that has the same
number as the original bearing. Note:4.0 litre
engines after #164637 have sized crankshafts
and bearings in three grades, indicated by
colour and letter. The codes are stamped into
the front throw of the crankshaft(see
illustration). Match replacement bearings by
the colour codes: pink (P), white (W) or
green (G) for main bearings; red (R), yellow (Y)
or blue (B) for the three grades of big-end
bearings.
10Remember, the oil clearance is the final
judge when selecting new bearing sizes. If you
have any questions or are unsure which
bearings to use, get help from a dealer parts
or service department.
2B•14 Engine removal and overhaul procedures
3261 Jaguar XJ6 20.1 When inspecting the main and big-end bearings, look for
these problems
20.9 Later model 4.0 litre engines have graded journals and
bearings, with the markings indicated on the front throw of the
crankshaft - “A” indicates the front of the engine, “B” indicates
the codes for the main journals/bearings, and “C” indicates the
connecting rod journal grades