15Check the valve stem-to-guide clearance
with a small hole gauge and micrometer, or a
small dial bore gauge (see illustration). Also,
check the valve stem deflection with a dial
indicator attached securely to the cylinder
head. The valve must be in the guide and
approximately 1/16-inch off the seat. The total
valve stem movement indicated by the gauge
needle must be noted, then divided by two to
obtain the actual clearance value. If it exceeds
the stem-to-guide clearance limit found in this
Chapter’s Specifications, the valve guides
should be renewed. After this is done, if
there’s still some doubt regarding the
condition of the valve guides they should be
checked by an automotive machine workshop
(the cost should be minimal).
Valves
16Carefully inspect each valve face for
uneven wear, deformation, cracks, pits and
burned areas. Check the valve stem for
scuffing and galling and the neck for cracks.
Rotate the valve and check for any obvious
indication that it’s bent. Look for pits and
excessive wear on the end of the stem. The
presence of any of these conditions indicates
the need for valve service by an automotive
machine workshop.
17Measure the margin width on each valve
(see illustration). Any valve with a margin
narrower than 1/32-inch will have to be
replaced with a new valve.
Valve components
18Check each valve spring for wear (on the
ends) and pits. Measure the free length and
compare it to this Chapter’s Specifications
(see illustration). Any springs that are shorter
than specified have sagged and should not be
re-used. The tension of all springs should be
pressure checked with a special fixture before
deciding that they’re suitable for use in a
rebuilt engine (take the springs to an
automotive machine workshop for this check).
Note:If any valve springs are found broken on
1988 or 1989 engines, all springs should be
replaced with the improved springs used in
1990 (after VIN 9EPCLA120245) and later
engines. They are identified with a white
stripe. If your engine has springs with white-
stripes, they have already been replaced, and
only broken ones need be replaced.
19Stand each spring on a flat surface and
check it for squareness (see illustration). If
any of the springs are distorted or sagged,
renew all of the springs.
20Check the spring retainers and keepers
for obvious wear and cracks. Any
questionable parts should be renewed, as
extensive damage will occur if they fail during
engine operation.
21If the inspection process indicates that the
valve components are in generally poor
condition and worn beyond the limits specified,
which is usually the case in an engine that’s
being overhauled, reassemble the valves in the
cylinder head and refer to Section 11 for valve
servicing recommendations.
11 Valves- servicing
5
1Because of the complex nature of the job
and the special tools and equipment needed,
servicing of the valves, the valve seats and the
valve guides, commonly known as a valve job,
should be done by a professional.
2The home mechanic can remove and
dismantle the cylinder head(s), do the initial
cleaning and inspection, then reassemble and
deliver them to a dealer service department or
an automotive machine workshop for the
actual service work. Doing the inspection will
enable you to see what condition the cylinder
head(s) and valvetrain components are in and
will ensure that you know what work and new
parts are required when dealing with an
automotive machine workshop.
3The dealer service department, or
automotive machine workshop, will remove
the valves and springs, will recondition or
renew the valves and valve seats, recondition
the valve guides, check and renew the valve
springs, spring retainers and keepers (as
necessary), replace the valve seals with new
ones, reassemble the valve components and
make sure the installed spring height is
correct. The cylinder head gasket surface will
also be resurfaced if it’s warped.
4After the valve job has been performed by a
professional, the cylinder head(s) will be in like
new condition. When the cylinder heads are
returned, be sure to clean them again before
refitting on the engine to remove any metal
particles and abrasive grit that may still be
present from the valve service or cylinder
head resurfacing operations. Use compressed
air, if available, to blow out all the oil holes and
passages.
12 Cylinder head- reassembly
2
1Regardless of whether or not the cylinder
head was sent to an automotive machine
workshop for valve servicing, make sure it’s
clean before beginning reassembly. Renew
the cylinder head rear plate gasket any time
that the engine is overhauled or the cylinder
head is reconditioned (see Part A of this
Chapter for renewal procedure).
2If the cylinder head was sent out for valve
servicing, the valves and related components
will already be in place. Begin the reassembly
procedure with paragraph 8.
3Refit new seals on each of the valve guides.
Gently push each valve seal into place until
it’s seated on the guide.
Caution: Don’t hammer on the valve seals
once they’re seated or you may damage
them. Don’t twist or cock the seals during
refitting or they won’t seat properly on the
valve stems.
2B•8 Engine removal and overhaul procedures
10.15 Use a small dial bore gauge to
determine the inside diameter of the valve
guides - subtract the valve stem diameter
to determine the stem-to-guide clearance10.17 The margin width on each valve
must be as specified (if no margin exists,
the valve cannot be re-used)
10.18 Measure the free length of each
valve spring with a dial or vernier caliper10.19 Check each valve spring for
squareness
3261 Jaguar XJ6
4Beginning at one end of the cylinder head,
lubricate and refit the first valve. Apply moly-
base grease or clean engine oil to the valve
stem.
5Place the spring seat or shim(s) over the
valve guide and set the valve spring and
retainer in place.
6Compress the springs with a valve spring
compressor and carefully refit the keepers in
the upper groove, then slowly release the
compressor and make sure the keepers seat
properly. Apply a small dab of grease to each
keeper to hold it in place if necessary (see
Haynes Hint).
7Repeat the procedure for the remaining
valves. Be sure to return the components to
their original locations - don’t mix them up!
13 Pistons/connecting rods-
removal
4
Note :Prior to removing the piston/connecting
rod assemblies, remove the cylinder head(s),
the sump and the oil pump transfer tubes by
referring to Chapter 2A.
1Use your fingernail to feel if a ridge has
formed at the upper limit of ring travel (about
1/4-inch down from the top of each cylinder).
If carbon deposits or cylinder wear have
produced ridges, they must be completely
removed with a special tool (see illustration).
Follow the manufacturer’s instructions
provided with the tool. Failure to remove the
ridges before attempting to remove the
piston/connecting rod assemblies may result
in piston damage.
2After the cylinder ridges have been
removed, turn the engine upside-down so the
crankshaft is facing up. Remove the screws
and the front and rear baffle plates from the
bottom of the engine block (see illustration).
3Before the connecting rods are removed,
check the endplay with a feeler gauge. Slide
the blade between the first connecting rod
and the crankshaft throw until the play is
removed (see illustration). The endplay is
equal to the thickness of the feeler gauge(s). If
the endplay exceeds the specified service
limit, new connecting rods will be required. Ifnew rods (or a new crankshaft) are installed,
the endplay may fall under the service limit (if
it does, the rods will have to be machined to
restore it - consult an automotive machine
workshop for advice if necessary). Repeat the
procedure for the remaining connecting rods.
4Check the connecting rods and caps for
identification marks. If they aren’t plainly
marked, use a small centre punch to make the
appropriate number of indentations on each rod
and cap (1, 2, 3, etc, depending on the cylinder
they’re associated with) (see illustration).
5Loosen each of the connecting rod cap nuts
1/2-turn at a time until they can be removed by
hand. Remove the number one connecting rod
cap and bearing insert. Don’t drop the bearing
insert out of the cap. Note:These engines use
special connecting rod and main bearing cap
bolts that are designed to be used one time
only. They can be used during Plastigage
checks, but must be replaced with new bolts
when the engine is finally reassembled.
6Slip a short length of plastic or rubber hose
over each connecting rod cap bolt to protect
the crankshaft journal and cylinder wall as the
piston is removed (see illustration).
7Remove the bearing insert and push the
connecting rod/piston assembly out through
the top of the engine. Use a wooden hammer
handle to push on the upper bearing surface
in the connecting rod. If resistance is felt,
double-check to make sure that all of the
ridge was removed from the cylinder.
Engine removal and overhaul procedures 2B•9
2B
13.2 Remove the screws (arrowed) and
remove the front and rear baffle plates13.3 Check the connecting rod side
clearance with a feeler gauge as shown
13.4 The connecting rods and caps should
be marked by cylinder number - if they
aren’t, mark them with a centre punch to
avoid confusion during reassembly13.6 To prevent damage to the crankshaft
journals and cylinder walls, slip sections of
hose over the connecting rod bolts before
removing the pistons
3261 Jaguar XJ6 13.1 A ridge reamer is required to remove
the ridge from the top of each cylinder -
do this before removing the pistons!
The keepers are easier to fit if a small
amount of grease is applied to keep
them in place
21 Engine overhaul-
reassembly sequence
1Before beginning engine reassembly, make
sure you have all the necessary new parts,
gaskets and seals as well as the following
items on hand:
Common hand tools
A 1/2-inch drive torque wrench
Piston ring refitting tool
Piston ring compressor
Short lengths of rubber or plastic hose to
fit over connecting rod bolts
Plastigauge
Feeler gauges
A fine-tooth file
New engine oil
Engine assembly lube or moly-base
grease
Gasket sealer
Thread locking compound
Special Jaguar tools:
Engine lifting brackets (18G 1465)
Timing damper simulator (18E 1436)
Camshaft TDC tool (18G 1433)
2In order to save time and avoid problems,
engine reassembly must be done in the
following general order:
Piston rings (Part B)
Crankshaft and main bearings (Part B)
Piston/connecting rod assemblies (Part B)
Rear main (crankshaft) oil seal (Part B)
Auxiliary shaft (Part A)
Timing chains and sprockets (Part A)
Oil pump (Part A)
Timing chain cover (Part A)
Cylinder head and lifters (Part A)
Camshafts (Part A)
Oil pick-up (Part A)
Sump (Part A)
Intake and exhaust manifolds (Part A)
Valve cover (Part A)
Flywheel/driveplate (Part A)
22 Piston rings- refitting
3
1Before refitting the new piston rings, the ring
end gaps must be checked. It’s assumed that
the piston ring groove clearance has been
checked and verified correct (see Section 18).
2Lay out the piston/connecting rod
assemblies and the new ring sets so the ring
sets will be matched with the same piston and
cylinder during the end gap measurement and
engine assembly.
3Insert the top (number one) ring into the first
cylinder and square it up with the cylinder
walls by pushing it in with the top of the piston
(see illustration). The ring should be near the
bottom of the cylinder, at the lower limit of
ring travel.
4To measure the end gap, slip feeler gauges
between the ends of the ring until a gauge
equal to the gap width is found (see
illustration). The feeler gauge should slide
between the ring ends with a slight amount of
drag. Compare the measurement to that
found in this Chapter’s Specifications. If the
gap is larger or smaller than specified,
double-check to make sure you have the
correct rings before proceeding.
5If the gap is too small, it must be enlarged
or the ring ends may come in contact with
each other during engine operation, which
can cause serious damage to the engine. The
end gap can be increased by filing the ring
ends very carefully with a fine file. Mount thefile in a vice equipped with soft jaws, slip the
ring over the file with the ends contacting the
file face and slowly move the ring to remove
material from the ends(see illustration).
Caution: When performing this operation,
file only from the outside in, and after the
correct gap is achieved, deburr the filed
ends of the rings with a fine whetstone.
6Excess end gap isn’t critical unless it’s
greater than Specifications. Again, double-
check to make sure you have the correct rings
for your engine.
7Repeat the procedure for each ring that will
be installed in the first cylinder and for each
ring in the remaining cylinders. Remember to
keep rings, pistons and cylinders matched.
8Once the ring end gaps have been
checked/corrected, the rings can be installed
on the pistons.
9The oil control ring (lowest one on the
piston) is usually installed first. It’s composed
of three separate components. Slip the
spacer/expander into the groove (see
illustration). If an anti-rotation tang is used,
make sure it’s inserted into the drilled hole in
the ring groove. Next, refit the lower side rail.
Don’t use a piston ring refitting tool on the oil
ring side rails, as they may be damaged.
Instead, place one end of the side rail into the
groove between the spacer/expander and the
ring land, hold it firmly in place and slide a
finger around the piston while pushing the rail
into the groove (see illustrations). Next, refit
the upper side rail in the same manner.
10After the three oil ring components have
been installed, check to make sure that both
Engine removal and overhaul procedures 2B•15
2B
22.3 When checking piston ring end gap,
the ring must be square in the cylinder
bore (this is done by pushing the ring down
with the top of a piston as shown)22.4 With the ring square in the cylinder,
measure the end gap with a feeler gauge22.5 If the end gap is too small, clamp a
file in a vice and file the ring ends (from the
outside in only) to enlarge the gap slightly
22.9a Refit the spacer/expander in the oil
control ring groove22.9b DO NOT use a piston ring refitting
tool when refitting the oil ring side rails
3261 Jaguar XJ6
4Remove the water pump mounting bolts
(see illustration).
Note 1:The water pump is sold as a complete
assembly, including the rear housing with the
hose connections. Unless the rear housing is
corroded or cracked, many Jaguar mechanics
only refit the pump assembly itself, using the
original rear housing with all its hoses intact.
However, if the engine has a great deal of
years or mileage on it, it would be a good idea
to renew those hoses as well, in which case
the new rear housing can be installed.
Note 2:There are three different lengths of
water pump bolts. The longer bolts retain the
pump and rear housing to the engine(see
illustration 7.3).
5If the pump doesn’t come loose right away,
tap it with a soft-faced hammer to break the
gasket seal. Be careful not to hit the radiator
fins with the pump during removal.
6Thoroughly clean all sealing surfaces,
removing all traces of gasket or sealant from
the back of the pump and the face of the
housing.
7Apply a bead of RTV sealant to the sealing
surface on the back of the pump. Refit the
pump and bolts, tightening the bolts to the
torque listed in this Chapter’s Specifications.
8Refit the remaining parts in the reverse
order of removal. Note:If the pump has been
renewed after many miles of usage, it’s a good
idea to also renew the hoses connected to the
water pump housing(see illustrations). Refer
to Chapter 2A for intake manifold removal to
access the coolant pipes and hoses. If you
have noticed water leaks or stains on the left
side of the engine, the leaks may be coming
from these pipes and hoses.
9Refill the cooling system (see Chapter 1),
run the engine and check for leaks and proper
operation.
9 Coolant temperature
sender unit- check and
renewal
2
Warning: Do not start this
procedure until the engine is
completely cool.
Check
1If the coolant temperature gauge is
inoperative, check the fuses first (Chapter 12).
2If the temperature gauge indicates
excessive temperature after running awhile,
see the Fault finding section at the rear of the
manual.
3If the temperature gauge indicates Hot as
soon as the engine is started cold, disconnect
the wire at the coolant temperature sender
(see illustration). If the gauge reading drops,
renew the sender unit. If the reading remains
high, the wire to the gauge may be shorted to
ground, or the gauge is faulty.
4If the coolant temperature gauge fails to
show any indication after the engine has been
warmed up, (approx. 10 minutes) and the
fuses checked out OK, shut off the engine.
Disconnect the wire at the sender unit and,
using a jumper wire, connect the wire to a
clean ground on the engine. Briefly turn on the
ignition without starting the engine. If the
gauge now indicates Hot, renew the sender
unit.
5If the gauge fails to respond, the circuit may
be open or the gauge may be faulty - see
Chapter 12 for additional information.
Renewal
6Drain the coolant (see Chapter 1).
7Disconnect the electrical connector from
the sender unit.8Using a deep socket or a spanner, remove
the sender unit.
9Refit the new unit and tighten it securely.
Do not use thread sealant as it may
electrically insulate the sender unit.
10Reconnect the wiring connector, refill the
cooling system and check for coolant leakage
and proper gauge function.
10 Heating and air conditioning
blower motors- circuit check
and component renewal
3
Warning: Later models are
equipped with airbags. To
prevent accidental deployment
of the airbag, which could cause
personal injury or damage to the airbag
system, DO NOT work in the vicinity of the
steering wheel or instrument panel. Jaguar
recommends that, on airbag-equipped
models, the following procedure should be
left to a dealer service department or other
repair workshop because of the special
tools and techniques required to disable
the airbag system.
1Disconnect the battery negative cable.
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.
2There are two blower motors, one under the
left side of the dash and one behind the glove
compartment (see illustration). If the blower
doesn’t work, check the fuse and all
connections in the circuit for looseness and
corrosion. Make sure the battery is fully
charged. To access the right blower, remove
the glove compartment liner, the glove
compartment door and the right lower dash
panel (see Chapter 11).
Warning: When working around
the area behind the glove box,
watch out for a strip of sheet
metal bracing that has a very
sharp edge (see illustration). Apply some
heavy duct tape to the edge of the brace
before beginning work in this area, or you
could injure your hands.
Cooling, heating and air conditioning systems 3•7
3
8.4 Remove the water pump mounting
bolts (arrows indicate five visible here)8.8a Once the water pump is removed, the
rear housing (arrowed) is held in place only
by the hoses - check them for leakage and
condition whenever the pump is disturbed8.8b The water pipe (arrowed) may need
new gaskets where it meets the block - the
pipe is best accessed from below or with
the intake manifold unbolted
9.3 The coolant temperature sender unit
(arrowed) is located in the top of the
thermostat housing - it is the sender unit
with the single wire
3261 Jaguar XJ6
same dimensions, amperage rating, cold
cranking rating, etc. as the original.
6Refitting is the reverse of removal.
4 Battery cables-
check and renewal
1
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.
1Periodically inspect the entire length of
each battery cable for damage, cracked or
burned insulation and corrosion. Poor battery
cable connections can cause starting
problems and decreased engine performance.
2Check the cable-to-terminal connections at
the ends of the cables for cracks, loose wire
strands and corrosion. The presence of white,
fluffy deposits under the insulation at the
cable terminal connection is a sign that the
cable is corroded and should be renewed.
Check the terminals for distortion, missing
mounting bolts and corrosion.
3When removing the cables, always
disconnect the negative cable first and hook it
up last or the battery may be shorted by the
tool used to loosen the cable clamps. Even if
only the positive cable is being renewed, be
sure to disconnect the negative cable from
the battery first (see Chapter 1 for further
information regarding battery cable removal).
4Disconnect the cables from the battery,
then trace each of them to their opposite ends
and detach them from the starter solenoid
and earth terminals. Note the routing of each
cable to ensure correct refitting.
5If you are replacing either or both of the old
cables, take them with you when buying new
items. It is vitally important that you replace
the cables with identical parts. Cables have
characteristics that make them easy to
identify: positive cables are usually red, larger
in cross-section and have a larger diameter
battery post clamp; earth cables are usually
black, smaller in cross-section and have a
slightly smaller diameter clamp for the
negative post.
6Clean the threads of the solenoid or earth
connection with a wire brush to remove rust
and corrosion. Apply a light coat of battery
terminal corrosion inhibitor, or petroleum jelly,
to the threads to prevent future corrosion.
7Attach the cable to the solenoid or earth
connection and tighten the mounting nut/bolt
securely.
8Before connecting a new cable to the
battery, make sure that it reaches the battery
post without having to be stretched.
9Connect the positive cable first, followed by
the negative cable.
5 Ignition system- general
information and precautions
1All models are equipped with a computerised
ignition system. The ignition system consists of
the ignition coil, the crankshaft position sensor,
the amplifier and the electronic control unit
(ECU). The ignition ECU controls the ignition
timing and advance characteristics for the
engine. The ignition timing is not adjustable,
therefore, changing the position of the distributor
will not change the timing in any way. Note:In
the event the distributor must be removed from
the engine, be sure to follow the precautions
described in Section 9 and mark the engine and
distributor with paint to ensure correct refitting. If
the distributor is not marked and Ihe crankshaft is
turned while the distributor is out of the engine,
have the distributor installed by a dealer service
department. The distributor must be installed
using a special alignment tool.
2The distributor is driven by the intermediate
shaft which also drives the power steering pump.
The crankshaft position sensor is located on the
front timing cover. It detects crank position by
pulsing an electronic signal to the ECU. This
signal is sent to the ECU to provide ignition
timing specifications.
3The computerised ignition system provides
complete control of the ignition timing by
determining the optimum timing in response to
engine speed, coolant temperature, throttle
position and vacuum pressure in the intake
manifold. These parameters are relayed to the
ECU by the crankshaft position sensor, throttle
potentiometer, coolant temperature sensor and
MAF sensor. Ignition timing is altered during
warm-up, idling and warm running conditions by
the ECU. This electronic ignition system also
consists of the ignition switch, battery, coil,
distributor, spark plug leads and spark plugs.
4Refer to a dealer parts department or car
accessory outlet for any questions concerning
the availability of the distributor parts and
assemblies. Testing the crankshaft position
sensor is covered in Chapter 6.
5When working on the ignition system, take
the following precautions:
a) Do not keep the ignition switch on for
more than 10 seconds if the engine will
not start.
b) Always connect a tachometer in
accordance with the manufacturer’s
instructions. Some tachometers may be
incompatible with this ignition system.
Consult a dealer service department
before buying a tachometer for use with
this vehicle.
c) Never allow the ignition coil terminals to
touch earth. Earthing the coil could result
in damage to the igniter and/or the
ignition coil.
d) Do not disconnect the battery when the
engine is running.
6 Ignition system- check
2
Warning: Because of the high
voltage generated by the
ignition system, extreme care
should be taken when working
on the ignition components. This not only
includes the amplifier, coil, distributor and
spark plug leads, but related components
such as connectors, tachometer and other
test equipment also.
1With the ignition switch turned to the “ON”
position, a “Battery” light or an “Oil Pressure”
light is a basic check for ignition and battery
supply to the ECU.
2Check all ignition wiring connections for
tightness, cuts, corrosion or any other signs of a
bad connection.
3Use a calibrated ignition tester to verify
adequate secondary voltage (25,000 volts) at
each spark plug (see illustration). A faulty or
poor connection at that plug could also result in a
misfire. Also, check for carbon deposits inside
the spark plug boot.
4Check for carbon tracking on the coil. If
carbon tracking is evident, renew the coil and be
sure the secondary wires related to that coil are
clean and tight. Excessive wire resistance or
faulty connections could damage the coil.
5Check for battery voltage to the ignition coil
(see illustration). If battery voltage is available,
check the ignition coil primary and secondary
resistance (see Section 8).
6Check the distributor cap for any obvious
signs of carbon tracking, corroded terminals or
cracks (see Chapter 1).
7Using an ohmmeter, check the resistance of
the spark plug leads. Each wire should measure
less than 25,000 ohms.
8Check for battery voltage to the ignition
amplifier (see Section 7). If battery voltage does
not exist, check the circuit from the ignition
switch (refer to the wiring diagrams at the end of
Chapter 12).
5•2 Engine electrical systems
6.3 To use a calibrated ignition tester
(available at most car accessory outlets),
remove a plug lead from a cylinder,
connect the spark plug boot to the tester
and clip the tester to a good earth - if there
is enough voltage to fire the plug, sparks
will be clearly visible between the
electrode tip and the tester body
3261 Jaguar XJ6
7Start the engine and observe the vacuum
gauge. At idle, there should be no vacuum
present. Raise the engine rpm and observe
the vacuum increase. This is a ported vacuum
source and therefore it should only register
vacuum when throttled.
8Check the operation of the EGR control
solenoid. Check for battery voltage to the EGR
control solenoid harness (see illustration). If
battery voltage is not available, check the
harness. Refer to the wiring diagrams at the
end of Chapter 12.
9If battery voltage is available to the EGR
control solenoid, have the EGR system
diagnosed by a dealer service department or
other qualified repair workshop.
EGR valve renewal
10Detach the vacuum hose, disconnect the
fitting that attaches the EGR pipe to the EGR
valve and remove the EGR valve from the
exhaust manifold and check it for sticking and
heavy carbon deposits. If the valve is sticking
or clogged with deposits, clean or renew it.
11Refitting is the reverse of removal.
7 Evaporative Emission
Control (EVAP) system
Note: Some models may have charcoal
canister vent plugs installed in the canister
from the factory. These blanking plugs must
be removed to allow proper pressure and
release within the EVAP system. Check the
charcoal canister for these additional plugs
and remove them. With the blanking plugs
installed, the fuel tank will collapse causing
rough running and hesitation and loss of
power under load.
General description
1This system is designed to trap and store
fuel that evaporates from the fuel tank, throttle
body and intake manifold that would normally
enter the atmosphere in the form of
hydrocarbon (HC) emissions.
2The Evaporative Emission Control (EVAP)
system consists of a charcoal-filled canister,
the lines connecting the canister to the fuel
tank, tank pressure control valve, purgecontrol valve and thermal vacuum valve (TVV)
(see illustration). Note: 1993 and 1994
models have a purge control solenoid that is
controlled by the ECU. This solenoid switches
vacuum to the purge control valve.
3Fuel vapours are transferred from the fuel
tank and throttle body to a canister where
they’re stored when the engine isn’t running.
When the engine is running, the fuel vapours
are purged from the canister by intake airflow
and consumed in the normal combustion
process.Note: The ECU will set a code 89 if
the purge control valve is defective or the
circuit has shorted.
4The fuel tank is equipped with a pressure
control valve. This valve opens and closes
according to the pressure increase and
decrease in the fuel tank.
Check
5Poor idle, stalling and poor driveability can
all be caused by an inoperative pressure relief
valve, split or cracked hoses or hoses
connected to the wrong fittings. Check the
fuel tank filler cap for a damaged or deformed
gasket.
6Evidence of fuel loss or fuel odour can be
caused by liquid fuel leaking from fuel lines, a
cracked or damaged canister, an inoperative
fuel tank control valve, disconnected,
misrouted, kinked, deteriorated or damaged
vapour or control hoses.
7Inspect each hose attached to the canister
for kinks, leaks and cracks along its entire
length. Repair or renew as necessary.
8Look for fuel leaking from the bottom of the
6•10 Emissions and engine control systems
6.8 Check for battery voltage to the EGR
control solenoid
3261 Jaguar XJ6
7.2 Schematic of the
EVAP system
6Carefully check to make sure the
suspension and steering components do not
make contact with the hoses. Have an
assistant push on the vehicle and also turn the
steering wheel from lock-to-lock during
inspection.
7Bleed the brake system (see Section 9).
Metal brake line renewal
8When replacing brake lines, use the proper
parts only. Do not use copper line for any
brake system connections. Purchase steel
brake lines from a dealer or motor factors..
9Unless you’re using factory renewal brake
lines, you may need a tubing bender to bend
the lines to the proper shape.
10First, remove the line you intend to renew,
lay it on a clean workbench and measure it
carefully. Obtain a new line of the same length
and bend it to match the pattern of the old
line.
Warning: Do not crimp or
damage the line. No bend should
have a smaller radius than
9/16-inch. Make sure the
protective coating on the new line is
undamaged at the bends.
11When refitting the new line, make sure it’s
well supported by the brackets, the routing
matches the original and there’s plenty of
clearance between moving or hot
components.
12After refitting, check the master cylinder
fluid level and add fluid as necessary. Bleed
the brake system as outlined in Section 9 and
test the brakes carefully before driving the
vehicle. Be sure there are no leaks.
9 Brake hydraulic system-
bleeding
2
Warning: Wear eye protection
when bleeding the brake
system. If the fluid comes in
contact with your eyes,
immediately rinse them with water and
seek medical attention.Note:Bleeding the hydraulic system is
necessary to remove any air which has entered
the system during removal and refitting of a
hose, line, caliper or master cylinder.
1It will probably be necessary to bleed the
system at all four brakes if air has entered the
system due to low fluid level or if the brake
lines have been disconnected at the master
cylinder.
2If a brake line was disconnected at only one
wheel, then only that caliper or wheel cylinder
must be bled.
3If a brake line is disconnected at a fitting
located between the master cylinder and any
of the brakes, that part of the system served
by the disconnected line must be bled.
4Bleed the right rear, the left rear, the right
front and the left front caliper, in that order,
when the entire system is involved.
5Remove any residual vacuum from the
servo and pressure in the anti-lock braking
system (if equipped) by applying the brake
about 30 times with the engine off.
6Remove the master cylinder reservoir cover
and fill the reservoir with brake fluid. Refit the
cover. Note:Check the fluid level often during
the bleeding operation and add fluid as
necessary to prevent the fluid level from falling
low enough to allow air into the master
cylinder.
7Have an assistant on hand, as well as a
supply of new brake fluid, an empty clear
plastic container, a length of 3/16-inch clear
tubing to fit over the bleed screws and a
spanner to open and close the bleed screws.
8Beginning at the right rear wheel, loosen the
bleed screw slightly, then tighten it to a point
where it is snug but can still be loosened
quickly and easily.
9Place one end of the tubing over the bleed
valve and submerge the other end in brake
fluid in the container (see illustration).
10Have the assistant pump the brakes a few
times to build pressure in the system, then
hold the pedal firmly depressed.
11While the pedal is held depressed, open
the bleed screw just enough to allow fluid to
flow from the caliper. Watch for air bubbles toexit the submerged end of the tube. When the
fluid flow slows after a couple of seconds,
close the screw and have your assistant
release the pedal.
12Repeat Steps 10 and 11 until no more air
is seen leaving the tube, then tighten the
bleed screw and proceed to the left rear
wheel, the right front wheel and the left
front wheel, in that order, and perform the
same procedure. Be sure to check the fluid in
the master cylinder reservoir frequently.
13Never reuse old brake fluid. It contains
contaminates and moisture which could
damage the braking system.
14Refill the master cylinder with fluid at the
end of the operation.
15Check the operation of the brakes. The
pedal should feel solid when depressed, with
no sponginess. If necessary, repeat the entire
process.
Warning: Do not drive the car if
in doubt about the effectiveness
of the brake system.
10 Handbrake cable-
adjustment
1
1Slowly apply the handbrake and count the
number of clicks at the lever. It should be fully
applied within three to five clicks. If the lever is
still not fully applied by the fifth click, adjust
the handbrake cable as follows:
2Raise the vehicle and place it securely on
axle stands.
3Loosen the locknut (see illustration)and
tighten the cable adjuster until all slack has
been removed. Tighten the locknut. Make
sure the wheels turn freely with the handbrake
lever released
4Lower the vehicle and recheck the
handbrake lever. It should now be properly
adjusted. If it’s now fully applied within three
to five clicks, raise the vehicle again and
readjust the cable at the adjuster.
5Make sure the handbrake holds the vehicle
on an incline.
9•10 Braking system
8.3b The connection (arrowed) for the rear
hose and line is located right above the
mounting bracket for the front corner of
the differential crossmember; remove the
hose as described in the previous
illustration9.9 When bleeding the brakes, a hose is
connected to the bleed screw at the caliper
or wheel cylinder and then submerged in
brake fluid - air will be seen as bubbles in
the tube and container (all air must be
expelled before moving to the next brake)
10.3 To adjust the handbrake cable,
loosen the locknut, then turn the adjuster
to remove any slack in the cable; be sure
to tighten the locknut when the cable is
properly adjusted
3261 Jaguar XJ6
1 General information
Warning: Whenever any of the
suspension or steering fasteners
are loosened or removed, they
must be inspected and if
necessary, replaced with new ones of the
same part number or of original equipment
quality and design. Torque wrench settings
must be followed for proper reassembly
and component retention. Never attempt
to heat, straighten or weld any suspension
or steering component. Instead, renew any
bent or damaged part.
The front suspension (see illustrations)
consists of unequal-length upper and lower
control arms, shock absorbers and coil
springs. The upper ends of the shocks are
attached to the body; the lower ends
are attached to the lower control arms. The
upper ends of the coil springs are seated
against the suspension crossmember; the
lower ends are seated against removable
plates which are bolted to the lower control
arms. The steering knuckles are attached to
balljoints in the upper and lower control arms.
An anti-roll bar is attached to the suspension
crossmember with a pair of bushing brackets
and to the lower control arms via a connecting
link at each end.The independent rear suspension (see
illustration)uses control arms and integral
shock absorber/coil spring units. The upper
ends of the shocks are attached to the body;
the lower ends are connected to the control
arms.
The steering system consists of the
steering wheel, a steering column, a universal
joint on the lower end of the steering shaft, a
rack-and-pinion power steering gear, a power
steering pump and a pair of tie-rods which
connects the steering gear to the steering
knuckles (see illustration).
2 Self-levelling rear
suspension system
1988 to 1992 models were equipped with a
system that provided hydraulic power for the
rear suspension and for the power brakes. As
the vehicle is loaded or unloaded, the rear
suspension is automatically adjusted to
maintain a constant ride height.
The system was discontinued on 1993 and
later models, which are equipped with
conventional shock absorber/coil spring units.
A kit is available from your Jaguar dealer
should you decide to retrofit the later,
conventional shocks to a pre-1993 vehicle.
Complete instructions for refitting the kit are
included in Section 10.
3 Anti-roll bar (front)-
removal and refitting
2
1Raise the front of the vehicle and support it
securely on axle stands.
2Remove the bolts from the anti-roll bar
brackets that attach the anti-roll bar to the
suspension crossmember (see illustration).
3Remove the nuts that attach the anti-roll
bar to the links (see illustration). If you’re
replacing the links themselves, or removing
the control arm, remove the nuts attaching the
links to the lower control arms.
Suspension and steering systems 10•3
10
1.3 Rear suspension
1 Hub carrier 2 Control arms 3 Crossmember mounting brackets 4 Crossmember
3.2 To detach the anti-roll bar from the
suspension crossmember, remove these
two bolts (arrowed) from each bushing
bracket
3261 Jaguar XJ6