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
The maintenance intervals in this manual are provided with the
assumption that you, not the dealer, will be carrying out the work.
These are the minimum maintenance intervals recommended by us for
vehicles driven daily. If you wish to keep your vehicle in peak condition
at all times, you may wish to perform some of these procedures moreoften. We encourage frequent maintenance, because it enhances the
efficiency, performance and resale value of your vehicle.
When the vehicle is new, it should be serviced by a factory-
authorised dealer service department, in order to preserve the factory
warranty.
Maintenance schedule 1•3
1
3261 Jaguar XJ6
Weekly, or every 250 miles (400 km)
m mCarry out all the operations given in “Weekly
checks”at the start of this manual.
m
mRenew the fuel filter (Section 18)
m mCheck the ignition system components (Section 19)
m mCheck the crankcase ventilation system
(Section 20)
m mCheck the condition and tension of the drivebelt(s)
(Section 21)
m mCheck the front wheel bearing adjustment and
repack with grease (Section 22)
m mCheck the propshaft fasteners are tightened to the
specified torque (Section 23)
m mCheck the front wheel alignment (Section 24)
m mCheck the headlight beam alignment (Section 25)
Every 7500 miles (12 000 km)
or 6 months, whichever comes first
In addition to the operations listed previously, carry out the following:
m mRenew the engine oil and filter (Section 3)
m mCheck the spark plugs (Section 4)
m mCheck the power hydraulics fluid level (Section 5)
m mCheck the battery (Section 6)
m mCheck all pipes and hoses for signs of damage or
leakage (Section 7)
m mCheck the automatic transmission fluid level
(Section 8)
m mCheck the differential oil level (Section 9)
m mCheck the condition of the exhaust system
(Section 10)
m mCheck the brake pads and discs for wear and
adjust the handbrake (Section 11)
m mCheck the steering and suspension components
for wear or damage and check the wheel nuts are
tightened to the correct torque (Section 12)
m mCheck the condition of the seat belts (Section 13)
m mLubricate all locks and hinges, and exposed cables
(Section 14)
m mCarry out a road test (Section 15)
Every 2 years, regardless of mileage
m
mRenew the coolant (Section 30)
Every 60 000 miles (96 000 km)
In addition to the operations listed previously, carry out the following:
m
mCheck the handbrake shoes for wear (Section 29)
Every 30 000 miles (48 000 km)
or 2 years, whichever comes first
In addition to the operations listed previously, carry out the following:
m mRenew the automatic transmission fluid and filter
(Section 26)
m mRenew the differential oil (Section 27)
m mRenew the brake fluid (Section 28)
Every 15 000 miles (24 000 km)
or 12 months, whichever comes first
In addition to the operations listed previously, carry out the following:
m mRenew the spark plugs (Section 16)
m mRenew the air cleaner element (Section 17)
3Inspect each of the new plugs for defects. If
there are any signs of cracks in the porcelain
insulator of a plug, don’t use it.
4Check the electrode gaps of the new plugs.
Check the gap by inserting the wire gauge of
the proper thickness between the electrodes
at the tip of the plug (see illustration). The
gap between the electrodes should be
identical to that listed in this Chapter’s
Specifications or on the VECI label (as
applicable). If the gap is incorrect, use the
notched adjuster on the feeler gauge body to
bend the curved side electrode slightly (see
illustration).
5If the side electrode is not exactly over the
centre electrode, use the notched adjuster to
align them.Caution: If the gap of a new plug must be
adjusted, bend only the base of the earth
electrode - do not touch the tip.
Removal
6To prevent the possibility of mixing up
spark plug leads, work on one spark plug at a
time. Remove the lead and boot from one
spark plug. Grasp the boot - not the lead - as
shown, give it a half twisting motion and pull
straight up (see illustration).
7If compressed air is available, blow any dirt
or foreign material away from the spark plug
area before proceeding (a common bicycle
pump will also work).
8Remove the spark plug (see illustration).9Whether you are replacing the plugs at this
time or intend to re-use the old plugs,
compare each old spark plug with the chart
shown on the inside back cover of this manual
to determine the overall running condition of
the engine.
Refitting
10Prior to refitting, apply a coat of anti-seize
compound to the plug threads (see
illustration). It’s often difficult to insert spark
plugs into their holes without cross-threading
them. To avoid this possibility, fit a short piece
of 3/8-inch internal diameter (ID) rubber hose
over the end of the spark plug (see Haynes
Hint). The flexible hose acts as a universal
joint to help align the plug with the plug hole.
Should the plug begin to cross-thread, the
hose will slip on the spark plug, preventing
thread damage. Tighten the plug to the torque
listed in this Chapter’s Specifications. In the
absence of a torque wrench, tighten each
plug until you feel it seat, and then by a further
quarter-turn only. Do not overtighten the
spark plugs.
11Attach the plug lead to the new spark
plug, again using a twisting motion on the
boot until it is firmly seated on the end of the
spark plug.
12Follow the above procedure for the
remaining spark plugs, replacing them one at
a time to prevent mixing up the spark plug
leads.
1•8Every 7500 miles or 6 months
4.4a Spark plug manufacturers
recommend using a wire-type gauge when
checking the gap - if the wire does not
slide between the electrodes with a slight
drag, adjustment is required4.4b To change the gap, bend the side
electrode only, as indicated by the arrows,
and be very careful not to crack or chip the
porcelain insulator surrounding the
centre electrode4.6 When removing the spark plug leads,
grasp only the boot and use a
twisting/pulling motion
4.8 Use a spark plug socket with a long
extension to unscrew the spark plugs
3261 Jaguar XJ6
4.1 Tools required for changing
spark plugs
1 Spark plug socket - This will have special
padding inside to protect the spark plug
porcelain insulator
2 Torque wrench - Although not mandatory,
use of this tool is the best way to ensure
that the plugs are tightened properly
3 Ratchet - to fit the plug socket
4 Extension - Depending on model and
accessories, you may need special
extensions and universal joints to reach
one or more of the plugs
5 Spark plug gap gauge - This gauge for
checking the gap comes in a variety of
styles. Make sure the gap for your engine
is included
4.10 Apply a coat of anti-seize compound
to the spark plug threads
A length of 3/8-inch ID rubber hose will
save time and prevent damaged
threads when refitting the spark plugs
silencer and catalytic converter. If the
components can come in contact with the
body or suspension parts, secure the exhaust
system with new mounts.
5Check the running condition of the engine
by inspecting inside the end of the tailpipe.
The exhaust deposits here are an indication of
engine state-of-tune. If the pipe is black and
sooty or coated with white deposits, the
engine is in need of a tune-up, including a
thorough fuel system inspection.
11 Braking system - general
check and adjustment
2
Warning: The dust created by
the brake system may contain
asbestos, which is harmful to
your health. Never blow it out
with compressed air and don’t inhale any
of it. An approved filtering mask should be
worn when working on the brakes. Do not,
under any circumstances, use petroleum-
based solvents to clean brake parts. Use
brake system cleaner only! Try to use non-
asbestos replacement parts whenever
possible.
Note: For detailed photographs of the brake
system, refer to Chapter 9.
1In addition to the specified intervals, the
brakes should be inspected every time the
wheels are removed or whenever a defect is
suspected. Any of the following symptoms
could indicate a potential brake system
defect: The vehicle pulls to one side when the
brake pedal is depressed; the brakes make
squealing or dragging noises when applied;
brake pedal travel is excessive; the pedal
pulsates; brake fluid leaks, usually onto the
inside of the tyre or wheel.
2The disc brakes have built-in electrical wear
indicators which cause a warning lamp to
illuminate on the instrument panel when
they’re worn to the renewal point. When the
warning light comes on, replace the pads
immediately or expensive damage to the
discs can result.
3Loosen the wheel nuts.
4Raise the vehicle and place it securely on
axle stands.
5Remove the wheels.
Disc brakes
6There are two pads (an outer and an inner)
in each caliper. The pads are visible through
inspection holes in each caliper (see Haynes
Hint).
7Check the pad thickness by looking at each
end of the caliper and through the inspection
hole in the caliper body. If the lining material is
less than the thickness listed in this Chapter’s
Specifications, replace the pads. Note:Keep
in mind that the lining material is riveted or
bonded to a metal backing plate and the metal
portion is not included in this measurement.8If it is difficult to determine the exact
thickness of the remaining pad material by the
above method, or if you are at all concerned
about the condition of the pads, remove the
caliper(s), then remove the pads from the
calipers for further inspection (see Chapter 9).
9Once the pads are removed from the
calipers, clean them with brake cleaner and
re-measure them with a ruler or a vernier
caliper.
10Measure the disc thickness with a
micrometer to make sure that it still has
service life remaining. If any disc is thinner
than the specified minimum thickness,
replace it (refer to Chapter 9). Even if the disc
has service life remaining, check its condition.
Look for scoring, gouging and burned spots. If
these conditions exist, remove the disc and
have it resurfaced (see Chapter 9).
11Before refitting the wheels, check all
brake lines and hoses for damage, wear,
deformation, cracks, corrosion, leakage,
bends and twists, particularly in the vicinity of
the rubber hoses at the calipers (see
illustration). Check the clamps for tightness
and the connections for leakage. Make sure
that all hoses and lines are clear of sharp
edges, moving parts and the exhaust system.
If any of the above conditions are noted,
repair, reroute or replace the lines and/or
fittings as necessary (see Chapter 9).
Hydraulic brake servo check
12Sit in the driver’s seat and perform the
following sequence of tests.
13Start the engine, run it for about a minute
and turn it off. Then firmly depress the brake
several times - the pedal travel should
decrease with each application.
14With the brake fully depressed, start the
engine - the pedal should move down a little
when the engine starts.
15Depress the brake, stop the engine and
hold the pedal in for about 30 seconds - the
pedal should neither sink nor rise.
16If your brakes do not operate as
described above when the preceding tests
are performed, the brake servo is either in
need of repair or has failed. Refer to Chapter 9
for the removal procedure.
Handbrake
17Slowly pull up on the handbrake and
count the number of clicks you hear until the
handle is up as far as it will go. The
adjustment should be within the specified
number of clicks listed in this Chapter’s
Specifications. If you hear more or fewer
clicks, it’s time to adjust the handbrake (refer
to Chapter 9).
18An alternative method of checking the
handbrake is to park the vehicle on a steep hill
with the handbrake set and the transmission
in Neutral (be sure to stay in the vehicle during
this check!). If the handbrake cannot prevent
the vehicle from rolling, it is in need of
adjustment (see Chapter 9). Whenever a fault
is suspected, the brake discs should be
removed and the handbrake assemblies
themselves should be visually inspected.
12 Steering
and suspension check
2
Note: The steering linkage and suspension
components should be checked periodically.
Worn or damaged suspension and steering
linkage components can result in excessive
and abnormal tyre wear, poor ride quality and
vehicle handling and reduced fuel economy.
For detailed illustrations of the steering and
suspension components, refer to Chapter 10.
With the wheels on the ground
1Park the vehicle on level ground, turn the
engine off and set the handbrake. Check the
tyre pressures and check that the wheel nuts
are tightened to the specified torque.
2Push down at one corner of the vehicle,
then release it while noting the movement of
the body. It should stop moving and come to
rest in a level position with one or two
bounces. When bouncing the vehicle up and
down, listen for squeaks and noises from the
suspension components.
3If the vehicle continues to move up-and-
down or if it fails to return to its original
1•12Every 7500 miles or 6 months
11.11 Check along the brake hoses
and at each fitting (arrowed) for
deterioration and cracks
3261 Jaguar XJ6
You will find an inspection hole like this
in each caliper - placing a ruler across
the hole should enable you to determine
the thickness of remaining pad material
for both inner and outer pads
and old bearings should never be installed on
new races.
15Use high-temperature front wheel bearing
grease to pack the bearings. Work the grease
completely into the bearings, forcing it
between the rollers, cone and cage from the
back side (see illustration).
16Apply a thin coat of grease to the spindle
at the outer bearing seat, inner bearing seat,
shoulder and seal seat.
17Put a small quantity of grease inboard of
each bearing race inside the hub. Using your
finger, form a dam at these points to provide
extra grease availability and to keep thinned
grease from flowing out of the bearing (see
illustration).
18Place the grease-packed inner bearing
into the rear of the hub and put a little more
grease outboard of the bearing.
19Place a new seal over the inner bearing
and tap the seal evenly into place until it’s
flush with the hub (see illustration).
20Carefully place the hub assembly onto the
spindle and push the grease-packed outer
bearing into position (see illustration).
Adjustment
21Refit the washer and spindle nut. Tighten
the nut only slightly (no more than 16Nm/12
lbf ft of torque).
22Rotate the hub slowly in a forward
direction while tightening the spindle nut toapproximately 27Nm (20 lbf ft) to seat the
bearings. Remove any grease or burrs which
could cause excessive bearing play later.
23Loosen the spindle nut 1/4-turn, then
using your hand (not a spanner of any kind),
tighten the nut until it’s snug. Refit the nut lock
and a new cotter pin through the hole in the
spindle and the slots in the nut lock. If the
nut lock slots don’t line up, remove the nut
lock and turn it slightly until they do (see
illustration).
24Bend the ends of the cotter pin until
they’re flat against the nut. Cut off any extra
length which could interfere with the dust cap.
25Refit the dust cap, tapping it into place
with a hammer.
26Refit the brake disc and caliper in the
reverse order of removal (see Chapter 9).
27Refit the wheel on the hub and tighten the
wheel nuts.
28Grasp the top and bottom of the tyre and
check the bearings in the manner described
earlier in this Section.
29Lower the vehicle and tighten the wheel
nuts to the torque listed in this Chapter’s
Specifications.
23 Propshaft check
2
1Referring to Chapter 8, check the propshaft
centre bearing, universal joint and flexible
coupling for signs of wear or damage and
check that the propshaft fixings are tightened
to the specified torque.
24 Front wheel alignment check
5
1Accurate wheel alignment requires access
to specialised test equipment and as such
should be entrusted to a suitably equipped
Jaguar dealer or a tyre specialist (refer to
Chapter 10).
25 Headlight beam check
5
1Accurate adjustment of the headlight beam
is only possible using optical beam-setting
equipment, and this work should therefore be
carried out by a Jaguar dealer or garage with
the necessary facilities (see Chapter 12).
1•18Every 15 000 miles or 12 months
22.15 Work the grease completely into the
bearing rollers22.17 Apply a thin layer of grease to the
inner and outer bearing races22.19 After refitting the inner wheel
bearing into the hub - press the grease
seal into place
22.20 Refit the hub assembly onto the
spindle - then push the grease-packed
outer bearing into position22.23 Position the nut lock on the spindle
nut so that it lines up with the cotter pin
hole - DO NOT loosen the spindle nut from
its snug position
3261 Jaguar XJ6
rebuilt engine or short block, some rebuilders
will not warranty their engines unless the
radiator has been professionally flushed. Also,
we don’t recommend overhauling the oil
pump - always refit a new one when an engine
is rebuilt.
Before beginning the engine overhaul, read
through the entire procedure to familiarise
yourself with the scope and requirements of
the job. Overhauling an engine isn’t difficult,
but it is time-consuming. Plan on the vehicle
being tied up for a minimum of two weeks,
especially if parts must be taken to an
automotive machine workshop for repair or
reconditioning. Check on availability of parts
and make sure that any necessary special
tools and equipment are obtained in advance.
Most work can be done with typical hand
tools, although a number of precision
measuring tools are required for inspecting
parts to determine if they must be renewed.
Often an automotive machine workshop will
handle the inspection of parts and offer
advice concerning reconditioning and
renewal. Note:Always wait until the engine
has been completely dismantled and all
components, especially the engine block,
have been inspected before deciding what
service and repair operations must be
performed by an automotive machine
workshop. Since the engine block’s condition
will be the major factor to consider when
determining whether to overhaul the original
engine or buy a rebuilt one, never purchase
parts or have machine work done on other
components until the engine block has been
thoroughly inspected. As a general rule, time
is the primary cost of an overhaul, so it
doesn’t pay to refit worn or substandard
parts.
If it turns out that a number of major
components are beyond reconditioning, it
may be cost effective to buy a factory-rebuilt
engine from a Jaguar dealership.
As a final note, to ensure maximum life and
minimum trouble from a rebuilt engine,
everything must be assembled with care in a
spotlessly-clean environment.
3 Vacuum gauge
diagnostic checks
2
A vacuum gauge provides valuable
information about what is going on in the
engine at a low cost. You can check for worn
rings or cylinder walls, leaking cylinder head or
intake manifold gaskets, incorrect carburettor
adjustments, restricted exhaust, stuck or
burned valves, weak valve springs, improper
ignition or valve timing and ignition problems.
Unfortunately, vacuum gauge readings are
easy to misinterpret, so they should be used
with other tests to confirm the diagnosis.
Both the absolute readings and the rate of
needle movement are important for accurate
interpretation. Most gauges measure vacuumin inches of mercury (in-Hg). As vacuum
increases (or atmospheric pressure decreases),
the reading will decrease. Also, for every
1000 foot increase in elevation above sea level;
the gauge readings will decrease about one
inch of mercury.
Connect the vacuum gauge directly to
intake manifold vacuum, not to ported (above
the throttle plate) vacuum (see illustration).
Be sure no hoses are left disconnected during
the test or false readings will result.
Before you begin the test, allow the engine
to warm up completely. Block the wheels and
set the handbrake. With the transmission in
Park, start the engine and allow it to run at
normal idle speed.
Warning: Carefully inspect the
fan blades for cracks or damage
before starting the engine. Keep
your hands and the vacuum
tester clear of the fan and do not stand in
front of the vehicle or in line with the fan
when the engine is running.
Read the vacuum gauge; an average,
healthy engine should normally produce
between 17 and 22 inches of vacuum with a
fairly steady needle.
Refer to the following vacuum gauge
readings and what they indicate about the
engines condition:
1A low steady reading usually indicates a
leaking gasket between the intake manifold
and carburettor or throttle body, a leaky
vacuum hose, late ignition timing or incorrect
camshaft timing. Check ignition timing with a
timing light and eliminate all other possible
causes, utilising the tests provided in this
Chapter before you remove the timing belt
cover to check the timing marks.
2If the reading is three to eight inches below
normal and it fluctuates at that low reading,
suspect an intake manifold gasket leak at an
intake port or a faulty injector.
3If the needle has regular drops of about two
to four inches at a steady rate the valves are
probably leaking. Perform a compression or
leak-down test to confirm this.
4An irregular drop or down-flick of the
needle can be caused by a sticking valve or
an ignition misfire. Perform a compression or
leak-down test and read the spark plugs.5A rapid vibration of about four in-Hg
vibration at idle combined with exhaust
smoke indicates worn valve guides. Perform a
leak-down test to confirm this. If the rapid
vibration occurs with an increase in engine
speed, check for a leaking intake manifold
gasket or cylinder head gasket, weak valve
springs, burned valves or ignition misfire.
6A slight fluctuation, say one inch up and
down, may mean ignition problems. Check all
the usual tune-up items and, if necessary, run
the engine on an ignition analyser.
7If there is a large fluctuation, perform a
compression or leak-down test to look for a
weak or dead cylinder or a blown cylinder
head gasket.
8If the needle moves slowly through a wide
range, check for a clogged PCV system,
incorrect idle fuel mixture, throttle body or
intake manifold gasket leaks.
9Check for a slow return after revving the
engine by quickly snapping the throttle open
until the engine reaches about 2,500 rpm and
let it shut. Normally the reading should drop to
near zero, rise above normal idle reading
(about 5 in.-Hg over) and then return to the
previous idle reading. If the vacuum returns
slowly and doesn’t peak when the throttle is
snapped shut, the rings may be worn. If there
is a long delay, look for a restricted exhaust
system (often the silencer or catalytic
converter). An easy way to check this is to
temporarily disconnect the exhaust ahead of
the suspected part and redo the test.
4 Cylinder compression check
2
1A compression check will tell you what
mechanical condition the upper end (pistons,
rings, valves, cylinder head gasket) of your
engine is in. Specifically, it can tell you if the
compression is down due to leakage caused
by worn piston rings, defective valves and
seats or a blown cylinder head gasket. Note:
The engine must be at normal operating
temperature and the battery must be fully
charged for this check.
2Begin by cleaning the area around the
spark plugs before you remove them
(compressed air should be used, if available,
otherwise a small brush or even a bicycle tyre
pump will work). The idea is to prevent dirt
from getting into the cylinders as the
compression check is being done.
3Remove all of the spark plugs from the
engine (see Chapter 1).
4Block the throttle wide open.
5Detach the coil wire from the centre of the
distributor cap and ground it on the engine
block. Use a jumper wire with alligator clips on
each end to ensure a good earth. Also,
remove the fuel pump relay (see Chapter 4) to
disable the fuel pump during the compression
test.
Engine removal and overhaul procedures 2B•3
2B
3.4 The vacuum gauge is easily attached
to a port on the intake manifold, and can
tell a lot about an engine’s state of tune
3261 Jaguar XJ6
3261 Jaguar XJ6
3
Chapter 3
Cooling, heating and air conditioning systems
General
Radiator cap pressure rating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13.5 to 117.5 psi
Thermostat rating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 180 to 207° F
Torque wrench settingsNm lbf ft
Coolant pipe to block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 to 28 16 to 21
Fan assembly-to-drive hub nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 to 28 16 to 21
Fan clutch-to-fan blade bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 to 28 16 to 21
Thermostat cover bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 to 28 16 to 21
Thermostat housing-to-block bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 to 28 16 to 21
Water pump bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 to 28 16 to 21 Air conditioning and heating system - check and maintenance . . . . 13
Air conditioning compressor - removal and refitting . . . . . . . . . . . . . 15
Air conditioning condenser - removal and refitting . . . . . . . . . . . . . . 16
Air conditioning evaporator and expansion valve - removal
and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Air conditioning receiver/drier - removal and refitting . . . . . . . . . . . . 14
Antifreeze/coolant - general information . . . . . . . . . . . . . . . . . . . . . . 2
Coolant level check . . . . . . . . . . . . . . . . . . . . . . . . . . . . See Chapter 1
Coolant temperature sender unit - check and renewal . . . . . . . . . . . .9
Cooling system check . . . . . . . . . . . . . . . . . . . . . . . . . . See Chapter 1
Cooling system draining, flushing and refilling . . . . . . . . See Chapter 1
Drivebelt check, adjustment and renewal . . . . . . . . . . . See Chapter 1
Engine cooling fans - check and renewal . . . . . . . . . . . . . . . . . . . . . 4Engine oil cooler - renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
General information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Heater and air conditioning blower motors -circuit check
and component renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Heater and air conditioning control assembly -
check, removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Heater core - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Radiator, expansion tank and coolant reservoir -
removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Thermostat - check and renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Underbonnet hose check and renewal . . . . . . . . . . . . . . See Chapter 1
Water pump - check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Water pump and pipes - renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
3•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
1 General information
Engine cooling system
All vehicles covered by this manual employ a
pressurised engine cooling system with
thermostatically-controlled coolant circulation.
An impeller type water pump mounted on the
front of the block pumps coolant through the
engine. The coolant flows around each cylinder
and toward the rear of the engine. Cast-in
coolant passages direct coolant around the
intake and exhaust ports, near the spark plug
areas and in proximity to the exhaust valve
guides.A wax-pellet type thermostat is located in
the thermostat housing at the front of the
engine. During warm up, the closed
thermostat prevents coolant from circulating
through the radiator. When the engine
reaches normal operating temperature, the
thermostat opens and allows hot coolant to
travel through the radiator, where it is cooled
before returning to the engine.
The cooling system is sealed by a pressure-
type radiator cap. This raises the boiling point
of the coolant, and the higher boiling point of
the coolant increases the cooling efficiency
of the radiator. If the system pressure exceeds
the cap pressure-relief value, the excess
pressure in the system forces the spring-
loaded valve inside the cap off its seat and
allows the coolant to escape through the
overflow tube into a coolant reservoir. Whenthe system cools, the excess coolant is
automatically drawn from the reservoir back
into the radiator. This type of cooling system is
known as a closed design because coolant
that escapes past the pressure cap is saved
and reused.
The Jaguar cooling system on 1988 and
1989 models has both a manifold tank and a
coolant recovery tank. The manifold tank is the
highest point in the cooling system and is the
location of the “radiator” cap (the cap is not on
the radiator). The recovery tank down in the
passenger’s footwell collects heated coolant
as described above. Models from 1990 to
1994 do not have a coolant recovery tank, but
have an enlarged manifold tank. In all models,
the recovery tank has a sensor in it to detect a
low coolant level, and the instrument panel has
a warning light to that effect.
Refitting
7Insert the distributor into the engine in
exactly the same relationship to the block that
it was in when removed.
8If the distributor does not seat completely,
recheck the alignment marks between the
distributor base and the block to verify that
the distributor is in the same position it was in
before removal. Also check the rotor to see if
it’s aligned with the mark you made on the
edge of the distributor base.
9Refit the distributor hold-down bolt(s).
10The remainder of refitting is the reverse of
removal.
10 Charging system- general
information and precautions
The charging system includes the alternator,
an internal voltage regulator, a charge
indicator light, load dump module, the battery,
an ignition ON relay, an in-line fuse and the
wiring between all the components (see
illustration). The charging system supplies
electrical power for the ignition system, the
lights, the radio, etc. The alternator is driven by
a drivebelt at the front of the engine.
The purpose of the voltage regulator is to
limit the alternator’s voltage to a preset value.
This prevents power surges, circuit overloads,
etc., during peak voltage output.
The alternator load dump module protects
the electrical circuits from excessive voltage
surges. When the battery cables are removed
large amounts of transient voltage is released
through the electrical circuits. This device
diverts up to 30 load volts of excess voltage to
earth by way of a voltage dependent resistor.
The in-line fuse is a special fuse installed
into the circuit with the engine compartment
wiring harness (see Chapter 12). The in-line
fuse protects the electrical system in the
event of excess voltage surges or a power to
earth short circuit. Refer to Chapter 12 for
additional information concerning the in-line
fuses and their locations.
1993 and 1994 models have a Starter Logic
Relay. This microprocessor (computer)
gathers information from the ignition switch,
linear gear position switch, park/neutral
switch, the security switch and the electronic
door lock system. If all the conditions are in
order, the computer allows battery voltage to
be transferred from the ignition switch to the
starter/solenoid assembly.
The charging system doesn’t ordinarily
require periodic maintenance. However, the
drivebelt, battery and wires and connections
should be inspected at the intervals outlined
in Chapter 1.
The dashboard warning light should come
on when the ignition key is turned to Start,
then should go off immediately. If it remains
on, there is a malfunction in the charging
system. Some vehicles are also equipped with
a voltage gauge. If the voltage gaugeindicates abnormally high or low voltage,
check the charging system (see Section 11).
Be very careful when making electrical
circuit connections to a vehicle equipped with
an alternator and note the following:
a) When reconnecting wires to the alternator
from the battery, note their polarity.
b) Before using arc welding equipment to
repair any part of the vehicle, disconnect
the wires from the alternator and the
battery terminals.
c) Never start the engine with a battery
charger connected.
d) Always disconnect both battery leads
before using a battery charger.
e) The alternator is driven by an engine
drivebelt which could cause serious injury
if your hand, hair or clothes become
entangled in it with the engine running.
f) Because the alternator is connected
directly to the battery, it could arc or
cause a fire if overloaded or shorted out.
g) Wrap a plastic bag over the alternator and
secure it with rubber bands before steam
cleaning the engine.
11 Charging system- check
2
Note:1993 and 1994 models are equipped
with a Starter Logic Relay. This microprocessor
(computer) gathers information from theignition switch, linear gear position switch,
park/neutral switch, the security switch and the
electronic door lock system. If all the conditions
are in order, the computer allows battery
voltage to be transferred from the ignition
switch to the starter/solenoid assembly. If all
the components of the charging system are
working properly and the system still does not
charge properly, have the Starter Logic Relay
diagnosed by a dealer service department.
1If a malfunction occurs in the charging
circuit, don’t automatically assume that the
alternator is causing the problem. First check
the following items:
a) Check the drivebelt tension and its
condition. Renew it if worn or damaged.
b) Make sure the alternator mounting and
adjustment bolts are tight.
c) Inspect the alternator wiring harness and
the electrical connectors at the alternator
and voltage regulator. They must be in
good condition and tight.
d) Check the fusible link (if equipped)
located between the starter solenoid and
the alternator or the large main fuses in
the engine compartment. If it’s burned,
determine the cause, repair the circuit
and renew the link or fuse (the vehicle
won’t start and/or the accessories won’t
work if the fusible link or fuse blows).
e) Check all the in-line fuses that are in series
with the charging system circuit (see
Chapter 12).The location of these fuses
and fusible links may vary from year and
Engine electrical systems 5•5
5
10.1 Schematic of a typical charging system
3261 Jaguar XJ6