ECU JAGUAR XJ6 1997 2.G User Guide

position, a worn or weak shock absorber is
probably the reason.
4Repeat the above check at each of the
three remaining corners of the vehicle.
Under the vehicle
5Raise the vehicle with a trolley jack and
support it securely on axle stands. See
“Jacking and towing”for proper jacking
points.
6Check the shock absorbers for evidence of
fluid leakage. Make sure that any fluid noted is
from the shocks and not from any other
source. Also check the rubber mounts at each
end for deterioration If the shock absorbers
fail any of the tests above replace the shocks
as a set.
7Check the tyres for irregular wear patterns
and proper inflation. See “Weekly checks”for
information regarding tyre wear.
8Inspect the universal joint between the
steering shaft and the steering gear housing.
Check the steering gear housing for grease
leakage. Make sure that the dust seals and
boots are not damaged and that the boot
clamps are not loose (see illustration). Check
the steering linkage for looseness or damage.
Look for loose bolts, broken or disconnected
parts and deteriorated rubber bushings on all
suspension and steering components (see
illustration). While an assistant turns the
steering wheel from side to side, check the
steering components for free movement,
chafing and binding. If the steering
components do not seem to be reacting with
the movement of the steering wheel, try to
determine where the slack is located.
9Check the balljoints moving each lower arm
up and down with a crowbar to ensure that its
balljoint has no play. If any balljoint does have
play, replace it. See Chapter 10 for the front
balljoint renewal procedure. Check the tie-rod
ends for excessive play.
10Inspect the balljoint and tie-rod end boots
for damage and leaking grease (see
illustration. Replace the balljoints and tie-rod
ends with new ones if they are damaged (see
Chapter 10).
13 Seat belt check
1
1Check the seat belts, buckles, latch plates
and guide loops for any obvious damage or
signs of wear.
2Make sure the seat belt reminder light
comes on when the key is turned on.
3The seat belts are designed to lock up
during a sudden stop or impact, yet allow free
movement during normal driving. The
retractors should hold the belt against your
chest while driving and rewind the belt when
the buckle is unlatched.
4If any of the above checks reveal problems
with the seat-belt system, replace parts as
necessary.Note:Check with your local dealer
service department; the seat belt system
should be covered under the factory warranty.
14 General lubrication
2
1Obtain a good quality, multi-purpose
lithium-base grease. You’ll also need a grease
gun and other materials to properly lubricate
the chassis (see illustration). Occasionallyplugs will be installed rather than grease
fittings. If so, grease fittings will have to be
purchased and installed.
2Look under the car and see if grease fittings
or plugs are installed. If there are plugs,
remove them and buy grease fittings, which
will thread into the component. A dealer or
motor factors will be able to supply the
correct fittings. Straight, as well as angled,
fittings are available.
3For easier access under the car, raise it with
a jack and place axle stands under the
chassis. Make sure it’s safely supported by
the stands. If the wheels are to be removed at
this interval for tyre rotation or brake
inspection, loosen the wheel nuts slightly
while the car is still on the ground.
4Before beginning, force a little grease out of
the nozzle to remove any dirt from the end of
the gun. Wipe the nozzle clean with a rag.
5With the grease gun and plenty of clean
rags, crawl under the car and begin
lubricating all the front suspension parts that
are equipped with a grease fitting.
6Lubricate the rear driveshafts (see
illustration). Wipe each fitting clean and push
the nozzle firmly over it. Pump the gun until
grease is expelled from the U-joint cap seal.
7Wipe away any excess grease from the
components and the grease fitting. Repeat
the procedure for the remaining fittings.
Every 7500 miles or 6 months 1•13
1
14.1 Materials required for chassis
and body lubrication
3261 Jaguar XJ6 12.8a Check the steering gear dust boots
for cracks and leaking steering fluid
12.8b Check the anti-roll bar bushings
(arrowed) for deterioration at the front and
the rear of the vehicle12.10 Inspect the balljoint and tie-rod end
boots for tears - tears or damage in either
boot will allow contamination of the grease
which will lead to premature failure
1 Engine oil - Light engine oil in a can like
this can be used for door and bonnet
hinges
2 Graphite spray - Used to lubricate lock
cylinders
3 Grease - Grease, in a variety of types and
weights, is available for use in a grease
gun.
4 Grease gun - A common grease gun,
shown here with a detachable hose and
nozzle, is needed for chassis lubrication.
After use, clean it thoroughly

16 Spark plug renewal
2
Refer to Section 4, renewing the plugs
regardless of their apparent condition.
17 Air cleaner element renewal
1
1The air filter is located inside a housing at
the left side of the engine compartment. To
remove the air filter, release the four spring
clips that secure the two halves of the air
cleaner housing together, then lift the cover
up and remove the air filter element (see
illustration).
Caution: Never drive the car with the air
cleaner removed. Excessive engine wear
could result and backfiring could even
cause a fire under the bonnet.
2Wipe out the inside of the air cleaner
housing.
3Place the new filter into the air cleaner
housing, making sure it seats properly.
4Refitting the cover is the reverse of removal.
18 Fuel filter renewal
2
Warning: Petrol is extremely
flammable, so take extra
precautions when you work on
any part of the fuel system.
Don’t smoke or allow open flames or bare
light bulbs near the work area, and don’t
work in a garage where a natural gas-typeappliance (such as a water heater or
clothes dryer) with a pilot light is present.
Since petrol is carcinogenic, wear latex
gloves when there’s a possibility of being
exposed to fuel, and, if you spill any fuel on
your skin, rinse it off immediately with soap
and water. Mop up any spills immediately
and do not store fuel-soaked rags where
they could ignite. The fuel system is under
constant pressure, so, if any fuel lines are
to be disconnected, the fuel pressure in
the system must be relieved first (see
Chapter 4 for more information). When you
perform any kind of work on the fuel
system, wear safety glasses and have a
Class B type fire extinguisher on hand.
1The canister type filter is mounted
underneath the car on the passenger’s side
frame rail just in front of the left rear tyre.
2Depressurise the fuel system (refer to
Chapter 4), then disconnect the cable from
the negative terminal of the battery.
3On 1988 to 1990 models, detach the banjo
bolt from the outlet side of the filter then
remove the union from the inlet side of the
filter. Unscrew the filter mounting bolt and
remove the filter (see illustration).
4On 1991 to 1994 models, the fuel filter has
quick-disconnect fittings that do not require 8Clean and lubricate the handbrake cable,
along with the cable guides and levers. This
can be done by smearing some of the chassis
grease onto the cable and its related parts
with your fingers.
9Open the bonnet and smear a little chassis
grease on the bonnet latch mechanism. Have
an assistant pull the bonnet release lever from
inside the car as you lubricate the cable at the
latch.
10Lubricate all the hinges (door, bonnet,
etc.) with engine oil to keep them in proper
working order.
11The key lock cylinders can be lubricated
with spray graphite or silicone lubricant, which
is available at motor factors.12Lubricate the door weather-stripping with
silicone spray. This will reduce chafing and
retard wear.
15 Road test
1
Instruments and electrical
equipment
1Check the operation of all instruments and
electrical equipment.
2Make sure that all instruments read
correctly, and switch on all electrical
equipment in turn, to check that it functions
properly.
Steering and suspension
3Check for any abnormalities in the steering,
suspension, handling or road “feel”.
4Drive the car, and check that there are no
unusual vibrations or noises.
5Check that the steering feels positive, with
no excessive “sloppiness”, or roughness, and
check for any suspension noises when
cornering and driving over bumps.
Drivetrain
6Check the performance of the engine and
transmission, listening for any unusual noises.7Make sure that the engine runs smoothly
when idling, and that there is no hesitation
when accelerating.
8Check that the gear changing action of the
transmission is smooth and progressive and
that the drive is taken up smoothly from a
standing start.
Braking system
9Make sure that the car does not pull to one
side when braking, and that the wheels do not
lock prematurely when braking hard.
10Check that there is no vibration through
the steering when braking.
11Check that the handbrake operates
correctly without excessive movement of the
lever, and that it holds the car stationary on a
slope.
12Test the operation of the brake servo unit
as follows. With the engine off, depress the
footbrake four or five times to exhaust the
vacuum. Hold the brake pedal depressed, then
start the engine. As the engine starts, there
should be a noticeable “give” in the brake
pedal as vacuum builds up. Allow the engine to
run for at least two minutes, and then switch it
off. If the brake pedal is depressed now, it
should be possible to detect a hiss from the
servo as the pedal is depressed. After about
four or five depressions, no further hissing
should be heard, and the pedal should feel
considerably harder.
1•14Every 7500 miles or 6 months
17.1 Detach the clips and separate the
cover, then slide the filter element out of
the housing
3261 Jaguar XJ6
14.6 Grease fittings for the rear
driveshafts are located in the centre
on each U-joint
Every 15 000 miles (24 000 km) or 12 months

hand tools to remove. Simply slide back the
locking collars and remove the inlet and outlet
fuel lines (see illustration). Detach the filter
mounting bracket and discard the old filter in
a proper container.
5Note the direction of the arrow on the
outside of the filter; it should be pointed
towards the front of the car. Make sure the
new filter is installed so that it’s facing the
proper direction. Note:Always refit new
copper washers where equipped.
6Refit the inlet and outlet fittings then tighten
the filter mounting bracket. Reconnect the
battery cable, start the engine and check for
leaks.
19 Ignition system check
2
1The spark plug leads should be checked
whenever new spark plugs are installed.
2Begin this procedure by making a visual
check of the spark plug leads while the engine
is running. In a darkened garage (make sure
there is adequate ventilation) start the engine
and observe each plug lead. Be careful not to
come into contact with any moving engine
parts. If there is a break in the lead, you will
see arcing or a small spark at the damaged
area. If arcing is noticed, make a note to
obtain new leads, then allow the engine to
cool and check the distributor cap and rotor.
3The spark plug leads should be inspected
one at a time to prevent mixing up the order,
which is essential for proper engine operation.
Each original plug lead should be numbered
to help identify its location. If the number is
illegible, a piece of tape can be marked with
the correct number and wrapped around the
plug lead.
4Disconnect the plug lead from the spark
plug. A removal tool can be used for this
purpose or you can grasp the rubber boot,
twist the boot half a turn and pull the boot
free. Do not pull on the lead itself.
5Check inside the boot for corrosion, which
will look like a white crusty powder.6Push the lead and boot back onto the end
of the spark plug. It should fit tightly onto the
end of the plug. If it doesn’t, remove the lead
and use pliers to carefully crimp the metal
connector inside the lead boot until the fit is
snug.
7Using a clean rag, wipe the entire length of
the lead to remove built-up dirt and grease.
Once the lead is clean, check for burns,
cracks and other damage. Do not bend the
lead sharply, because the conductor might
break.
8Disconnect the spark plug lead from the
distributor cap. Again, pull only on the rubber
boot. Check for corrosion and a tight fit.
Reinsert the lead in the distributor cap.
9Inspect the remaining spark plug leads,
making sure that each one is securely
fastened at the distributor and spark plug
when the check is complete.10If new spark plug leads are required,
purchase a set for your specific engine model.
Remove and replace the leads one at a time
to avoid mix-ups in the firing order.
11Detach the distributor cap by unsnapping
the cap retaining clips. Look inside it for
cracks, carbon tracks and worn, burned or
loose contacts (see illustrations).
12Pull the rotor off the distributor shaft and
examine it for cracks and carbon tracks (see
illustrations). Replace the cap and rotor if any
damage or defects are noted.
13It is common practice to refit a new cap
and rotor whenever new spark plug leads are
installed. When refitting a new cap, remove
the leads from the old cap one at a time and
attach them to the new cap in the exact same
location Note:If an accidental mix-up occurs,
refer to the firing order Specifications at the
beginning of this Chapter.
Every 15 000 miles or 12 months 1•15
1
19.11a Unsnap the distributor cap
retaining clips - pull the cap up and away
to access the rotor
19.11b Shown here are some of the
common defects to look for when
inspecting the distributor cap (typical cap
shown). If in doubt about its condition,
fit a new one
19.12a Pull off the rotor (arrowed) and
inspect it thoroughly
19.12b Check the ignition rotor for wear
and corrosion as indicated here (if in doubt
about its condition, buy a new one)
3261 Jaguar XJ6 18.3 Remove the banjo bolt from the
outlet side (B), detach the fitting from the
inlet side (A) and unscrew the filter
mounting bolt (C)
18.4 On 1991 to 1994 models, slide back
the locking collars and remove the inlet
and outlet fuel lines

compressor belt first because of the way they
are arranged on the crankshaft pulley.
Because of this and because belts tend to
wear out more or less together, it is a good
idea to replace both belts at the same time.
Mark each belt and its appropriate pulley
groove so the new belts can be installed in
their proper positions.
10Take the old belts to the parts store in
order to make a direct comparison for length,
width and design.
11After replacing a ribbed drivebelt, make
sure that it fits properly in the ribbed grooves
in the pulleys (see illustration). It is essential
that the belt be properly centred.
12Adjust the belt(s) in accordance with the
procedure outlined above.
22 Front wheel bearing check
and adjustment
3
Check and repack
1In most cases the front wheel bearings will
not need servicing until the brake pads are
changed. However, the bearings should be
checked whenever the front of the vehicle is
raised for any reason. Several items, including
a torque wrench and special grease, are
required for this procedure (see illustration).2With the vehicle securely supported on axle
stands, spin each wheel and check for noise,
rolling resistance and freeplay.
3Grasp the top of each tyre with one hand
and the bottom with the other. Move the
wheel in-and-out on the spindle. If there’s any
noticeable movement, the bearings should be
checked and then repacked with grease or
renewed if necessary.
4Remove the wheel.
5Remove the brake caliper (see Chapter 9)
and hang it out of the way on a piece of wire.
A wood block of the appropriate width can be
slid between the brake pads to keep them
separated, if necessary. Also remove the
brake disc.
6Pry the dust cap out of the hub using a
screwdriver or a hammer and chisel (see
illustration).
7Straighten the bent ends of the cotter pin,
then pull the cotter pin out of the nut lock (see
illustration).Discard the cotter pin and use a
new one during reassembly.
8Remove the locknut, nut and washer from
the end of the spindle.
9Pull the hub out slightly, then push it back
into its original position. This should force theouter bearing off the spindle enough so it can
be removed (see illustration).
10Pull the hub off the spindle. Note:
Sometimes the inner wheel bearing and
grease seal remain attached to the spindle.
Grasp the back of the seal with both hands
and pull forward to remove them.
11If the grease seal is not already detached
from the hub, use a screwdriver to pry the seal
out of the rear of the hub. As this is done, note
how the seal is installed.
12If the inner wheel bearing is not already
detached from the hub, remove it at this time.
13Use solvent to remove all traces of the old
grease from the bearings, hub and spindle. A
small brush may prove helpful; however make
sure no bristles from the brush embed
themselves inside the bearing rollers. Allow
the parts to air dry.
14Carefully inspect the bearings for cracks,
heat discoloration, worn rollers, etc. Check
the bearing races inside the hub for wear and
damage. If the bearing races are defective,
the hubs should be taken to a machine
workshop with the facilities to remove the old
races and press new ones in. Note that the
bearings and races come as matched sets
Every 15 000 miles or 12 months 1•17
1
22.1 Tools and materials needed for front
wheel bearing maintenance
1 Hammer
2 Grease - High-temperature grease that is
formulated specially for front wheel
bearings should be used
3 Wood block - If you have a scrap piece
of 2x4, it can be used to drive the new
seal into the hub
4 Needle-nose pliers - Used to straighten
and remove the cotter pin in the spindle
5 Torque wrench - This is very important in
this procedure; if the bearing is too tight,
the wheel won’t turn freely - if it’s too
loose, the wheel will “wobble” on the
spindle. Either way, it could mean
extensive damage
6 Screwdriver - Used to remove the seal
from the hub (a long screwdriver is
preferred)
7 Socket/breaker bar - Needed to loosen the
nut on the spindle if it’s extremely tight
8 Brush - Together with some clean
solvent, this will be used to remove old
grease from the hub and spindle
22.6 Dislodge the dust cap by working
around the outer circumference with a
hammer and chisel
22.7 Remove the cotter pin and discard it -
use a new one when the hub is reinstalled22.9 Pull the hub assembly forward
slightly - then push it back into position to
dislodge the outer wheel bearing
3261 Jaguar XJ6 21.11 When refitting ribbed (serpentine)
drivebelts, make sure the belt is centred
between the pulley edges (arrowed) - it
must not overlap either edge of the pulley

26 Automatic transmission fluid
and filter renewal
2
1At the specified time intervals, the
transmission fluid should be drained and
renewed. Since the fluid will remain hot long
after driving, perform this procedure only after
the engine has cooled down completely.
2Before beginning work, purchase the
specified transmission fluid and a new filter.
3Other tools necessary for this job include
axle stands to support the vehicle in a raised
position, a drain pan capable of holding at
least eight pints, newspapers and clean rags.4Raise the vehicle and support it securely on
axle stands.
5Place the drain pan under the drain plug in
the bottom of the transmission sump pan.
Remove the plug and allow the fluid to drain
(see illustration).
6Refit the drain plug, then move the drain
pan underneath the dipstick tube. Loosen the
dipstick tube collar and let the remaining fluid
drain (see illustrations).
7Remove the sump pan mounting bolts and
brackets (see illustration).
8Detach the sump pan from the transmission
and lower it, keeping it as horizontal as
possible in order not to spill too much of the
remaining fluid (see illustration).9Drain the remaining fluid from the
transmission sump pan, clean it with solvent
and dry it with compressed air. Be sure to
clean the metal filings from the magnet, if
equipped.
10Remove the screws and detach the filter
from the valve body (see illustrations).
11Refit the new O-ring and filter, being sure
to tighten the bolts securely.
12Carefully clean the fluid pan-to-
transmission sealing surface.
13Make sure the gasket surface on the
transmission sump pan is completely clean,
then refit the gasket. Put the sump pan in
place against the transmission and refit the
brackets and bolts. working around the sump
pan, tighten each bolt a little at a time until the
torque listed in this Chapter’s Specifications
is reached. Don’t overtighten the bolts!
Connect the dipstick tube and tighten the
collar securely.
14Lower the vehicle and add the specified
amount of fluid through the filler tube (see
Section 8).
15With the transmission in Park and the
handbrake set, run the engine at fast idle, but
don’t race it.
16Move the gear selector through each
position, and then back to Park. Check the
fluid level.
17Be sure to check underneath the car for
any leaks after the first few miles of driving.
Every 30 000 miles (48 000 km) or 2 years
Every 30 000 miles or 2 years 1•19
1
26.6a Unscrew the dipstick tube collar26.6b Detach the tube and let the
remaining fluid drain
26.7 Use a socket and extension to
remove the transmission sump pan bolts
and brackets26.8 Lower the sump pan from the
transmission
26.10a Use a Torx-head driver to remove
the filter bolts (arrowed) . . .
3261 Jaguar XJ6
26.5 Using an Allen spanner remove the
drain plug located in the bottom of the
transmission sump pan
26.10b . . . then remove the fluid filter from
the transmission26.10c Be sure to remove the old O-ring
from the transmission - always use a new
O-ring when replacing the filter

30 Coolant renewal
2
Warning: Do not allow engine
coolant (antifreeze) to come in
contact with your skin or painted
surfaces of the vehicle. Rinse off
spills immediately with plenty of water.
Antifreeze is highly toxic if ingested. Never
leave antifreeze laying around in an open
container or in puddles on the floor;
children and pets are attracted by it’s
sweet smell and may drink it. Check with
local authorities about disposing of used
antifreeze. Your local authority may have
collection centres which will see that
antifreeze is disposed of safely.1Periodically, the cooling system should be
drained, flushed and refilled to replenish the
antifreeze mixture and prevent formation of
rust and corrosion, which can impair the
performance of the cooling system and
cause engine damage. When the cooling
system is serviced, all hoses and the radiator
cap should be checked and renewed if
necessary.
Draining
2Apply the handbrake and block the wheels.
If the vehicle has just been driven, wait several
hours to allow the engine to cool down before
beginning this procedure.
3Remove the expansion tank pressure cap
(see illustration).
4Move a large container under the radiator
drain to catch the coolant. Then using a largescrewdriver, open the radiator drain plug and
direct the coolant into the container (see
illustration).
27 Differential oil renewal
2
1Drive the car for several miles to warm up
the differential lubricant, then raise the car
and support it securely on axle stands.
2Move a drain pan, rags, newspapers and
the required tools under the car.
3Remove the check/fill plug from the
differential. If necessary refer to Section 9 for
the check/fill plug location.
4With the drain pan under the differential,
use a ratchet and socket to loosen the drain
plug (see illustration). Note:A special pipe
plug socket may be required to complete this
procedure.
5Once loosened, carefully unscrew it with
your fingers until you can remove it from the
case. Since the lubricant will be hot, wear a
rubber glove to prevent burns.
6Allow all of the oil to drain into the pan, then
replace the drain plug and tighten it securely.
7Refer to Section 9 and fill the differential
with lubricant.
8Refit the fill plug and tighten it securely.
9Lower the vehicle. Check for leaks at the
drain plug after the first few miles of driving.
28 Brake fluid renewal
2
Warning: Brake fluid can harm
your eyes and damage painted
surfaces, so use extreme
caution when handling or
pouring it. Do not use brake fluid that has
been standing open or is more than oneyear old. Brake fluid absorbs moisture from
the air. Excess moisture can cause a
dangerous loss of braking effectiveness.
1At the specified time intervals, the brake
fluid should be drained and renewed. Since
the brake fluid may drip or splash when
pouring it, place plenty of rags around the
master cylinder to protect any surrounding
painted surfaces.
2Before beginning work, purchase the
specified type of brake fluid.
3Remove the cap from the master cylinder
reservoir.
4Using a hand suction pump or similar
device, withdraw the fluid from the master
cylinder reservoir.
5Add new fluid to the master cylinder until it
rises to the base of the filler neck.
6Bleed the brake system as described in
Chapter 9 at all four brakes until new and
uncontaminated fluid flows from the bleed
screw.
7Refill the master cylinder with fluid and
check the operation of the brakes. The pedal
should feel solid when depressed, with no
sponginess.
Warning: Do not drive the car if
you are in any doubt about the
braking system.
1•20Every 30 000 miles or 2 years
27.4 The differential drain plug (arrowed)
is accessible through a hole located in the
middle of the differential support brace
30.3 Push the expansion tank pressure
cap downward and rotate anti-clockwise -
never remove it when the engine is hot!
3261 Jaguar XJ6
Every 60 000 miles (96 000 km)
29 Handbrake shoes check
2
1Remove the rear discs and inspect the
handbrake shoes as described in Chapter 9. If
the shoes are worn or damaged they must be
renewed.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. Usebrake system cleaner only! Try to use non-
asbestos replacement parts whenever
possible.
Every 2 years, regardless of mileage

12Remove the four bolts in each camshaft
inner sprocket (see illustration). The bolts are
secured by sheetmetal “washer” plates. Bend
down the locking tabs with a hammer and
screwdriver tip to remove the bolts.
Caution: Stuff rags below the sprockets
while removing the bolts to prevent a bolt
from falling down into the front cover.
13Remove the two bolts retaining the upper
chain guide to the cylinder head (see
illustration).
14Pull the inner sprockets from each
camshaft (see illustration). Each camshaft
sprocket is comprised of an inner and outer,
each with a set of fine splines that lock them
together. The outer sprockets, with the teeth,
can rotate on the camshafts until the inner
sprocket bolts are tightened.
15Pull the outer sprockets from the
camshafts and allow the chain slacken.
16At this point the camshafts can be
carefully lifted straight up and off the cylinder
head. Take care not to nick any of the lobes or
journals during removal.
17Use a magnet to remove the lifters,
keeping them in order in a divided, numbered
box (see illustration). They must be returned
to their original location if reusing the original
camshafts!
18Removing the lifters exposes the
adjusting shims, sitting in a pocket in eachvalve spring retainer (see illustration). Keep
the shims with their matching lifters. Measure
the thickness of each shim with a micrometer
and record the measurements.
Inspection
19After the camshaft has been removed
from the engine, cleaned with solvent and
dried, inspect the bearing journals for uneven
wear, pitting and evidence of seizure. If the
journals are damaged, the bearing surfaces in
the cylinder head and caps may be damaged
as well, requiring renewal of the cylinder head.
20Measure the bearing journals with a
micrometer to determine if they are excessivelyworn or out-of-round (see illustration).
Compare the measurements to Specifications.
21Check the camshaft lobes for heat
discolouration, score marks, chipped areas,
pitting and uneven wear. Measure the lobe
heights with a micrometer and record the
measurements (see illustrations). If there is
variance of more than 0.005-inch, the
camshaft and lifters must be renewed. If the
lobes are in good condition, the camshaft can
be reused.
22Inspect the top, bottom and side surfaces
of the lifters for wear, grooving or scoring. If
the lifters are damaged, the camshaft and its
lifters must be renewed as a set.
Engine in-car repair procedures 2A•11
2A
10.13 Remove the two bolts and the upper
timing chain guide (arrowed)10.14 Pull the inner sprocket from the
outer sprocket of each camshaft
10.17 A magnet can be used to remove
the lifters (arrowed)10.18 The valve adjustment shims
(arrowed) fit into a pocket in the valve
spring retainer - use a magnet to remove
the shims and keep them with their
respective lifters10.20 Measure the bearing journals with a
micrometer to check diameter - measure
at several places around the journal to
check for taper or out-of-round
3261 Jaguar XJ6 10.12 Bend back the locking tabs
(arrowed) and remove the camshaft
sprocket bolts
10.21a Measure the camshaft lobe at its
greatest dimension . . .10.21b . . . and subtract the camshaft lobe
diameter at its smallest dimension to
obtain the lobe lift

Refitting
23If the valve clearance for any valve is
incorrect, as measured in paragraph 4, refit a
thicker or thinner shim on that valve. For
example, if the clearance had been too large
by 0.004-inch (compared to the recommended
clearance in the Specifications), replace the
existing shim there with a new one that is
0.004-inch thicker. If the clearance was too
small, use a shim that is smaller than the
original. Shims are identified alphabetically, in
sizes from 0.085-inch (designated size A, the
smallest) to 0.108-inch (designated size X, the
thickest).
24Lubricate the lifters with a thin coat of
moly-based lubricant on the top, bottom and
sides and refit them in their original positions.
25Lubricate the camshafts with moly-based
grease on the journals and lobes and lay them
carefully in their bearing saddles.
26Using NEW cylinder head bolts, replace
the spacers, one at a time, with the bearing
caps and bolts. Tighten the cap bolts, then
the cylinder head bolts to the torque listed in
this Chapter’s Specifications. The front capshould be installed first, then cap number 7,
then alternately tighten the first and last caps
to bring the camshaft down evenly. Next refit
caps 4, 2, 3, 5, and 6.
27Align the intake camshaft with the special
camshaft positioning tool as described in
paragraph 5. Engage the outer sprocket with
the chain, slip the sprocket over the end of the
camshaft, then turn it until there is no slack in
the chain to the right of the camshaft sprocket
(facing the front of the engine). Now align the
inner sprocket with the camshaft until the bolt
holes align and mesh the splines between the
two sprocket halves (see illustrations).
Tighten the inner sprocket bolts to the
camshaft and bend the locking sheetmetal
tabs over the bolts.
28Keeping the slack in the chain to the left
of the exhaust camshaft, refit the exhaust
camshaft outer sprocket, meshed with the
chain, over the end of the exhaust camshaft.
Insert the timing chain tensioner tool (Jaguar
tool no. 18G 1436) at the upper tensioner
mounting point (see illustration). Note:The
chain tensioner tool applies pressure to the
upper timing chain to simulate the effect of thetensioner, which is operated by engine oil
pressure when the engine is running.
29Align the exhaust camshaft to TDC with
the special timing gauge tool. Tighten the
centre bolt in the tensioner tool to 4 to 6 Nm.
When the chain is tensioned, align the inner
exhaust sprocket with the bolt holes in the
camshaft, engage the splines between the
two sprocket halves and secure the sprocket
with the bolts and locking tabs. Refit the clip
to secure the two sprocket halves together.
30Clean the tensioner gasket surface, fit a
new gasket and O-rings, push the ratchet
down and twist it to maintain the fully
retracted position, and refit the tensioner in
place of the tensioning tool (see illustration).
Note:Align the slot in the end of the tensioner
straight up and down to fit over the tang on
the back of the chain tensioner guide.
31Rotate the engine and recheck that all
valve clearance measurements are now
correct (see paragraph 4).
32The remainder of refitting is the reverse of
the removal procedure. Note:When refitting
the distributor, use a new O-ring where it fits
into the engine block.
2A•12 Engine in-car repair procedures
3261 Jaguar XJ6 10.27a Each camshaft sprocket is comprised of two sections, an
inner (A) and outer (B) that are splined together
10.27b Push the outer sprocket over the intake camshaft until it
locks in place - then turn the sprocket left to remove chain slack
at the right
10.28 The special tensioning tool simulates the operation of the
oil-driven tensioner - apply 4 to 6 Nm (36 to 48 inch-pounds)
pressure on the centre bolt (arrowed)10.30 Upper timing chain tension components
A Notch (to align
with tang on guide)B Tensioner ratchet
C O-ringD Gasket
E valve (with O-rings)

11 Cylinder head-
removal and refitting
4
Note:The engine must be completely cool
before beginning this procedure.
Removal
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.
2Drain the coolant from the engine block and
radiator (see Chapter 1).
3Drain the engine oil and remove the oil filter
(see Chapter 1).
4Remove the bonnet for easier access, if
necessary (see Chapter 11).
5Remove the intake manifold (see Section 5).
6Remove the exhaust manifolds (Section 6).
7Remove the valve cover (see Section 4).
8Refer to Section 3 and Position the engine
at TDC for cylinder number 1. Remove the
distributor (see Chapter 5).
9Remove the camshafts and sprockets (see
Section 10). Place the upper chain between
the two upper chain guides and wrap a large
rubber band around the two guides, retaining
the chain and guides.
10Remove the coolant housing from the
cylinder head (see illustration).
11Remove the cylinder head-to-front cover
bolts (see illustration).
12Using a socket and breaker bar, loosen
the cylinder head bolts in quarter-turn
increments until they can be removed by
hand. Loosen the cylinder head bolts using
the opposite of the recommended tightening
sequence (see illustration 11.23)to avoid
warping or cracking the cylinder head.
13Lift the cylinder head off the engine block.
If it’s stuck, very carefully pry up at the
transmission end, beyond the gasket surface.
Caution: Though the cylinder head is
aluminium, it is still heavy, large andawkward to handle. To avoid damaging the
body during removal, use an engine hoist
to lift the cylinder head out of the engine
compartment, or have an assistant help
you.
14With the cylinder head on a workbench,
remove all external components from the
cylinder head to allow for thorough cleaning
and inspection. See Chapter 2, Part B, for
cylinder head servicing procedures.
Refitting
15The mating surfaces of the cylinder head
and engine block must be perfectly clean
when the cylinder head is installed.
16Use a gasket scraper to remove all traces
of carbon and old gasket material, then clean
the mating surfaces with lacquer thinner or
acetone. If there’s oil on the mating surfaces
when the cylinder head is installed, the gasket
may not seal correctly and leaks could
develop. When working on the engine block,
stuff the cylinders with clean workshop rags
to keep out debris. Use a vacuum cleaner to
remove material that falls into the cylinders.
Caution: Use care when cleaning the
cylinder head gasket surface. The cylinder
head and engine block are aluminium and
can be easily damaged by using sharpscraping tools. Gasket removal solvents
are available from car accessory outlets
and may be useful for safe removal of
gasket material.
17Check the engine block and cylinder head
mating surface for nicks, deep scratches and
damage from coolant corrosion. If damage is
slight, it can be removed with a file; if it’s
excessive, machining may be the only
alternative. See Part B of this Chapter for
procedures and criteria concerning the repair
of corrosion damage.
18Use a tap of the correct size to chase the
threads in the cylinder head bolt holes, then
clean the holes with compressed air - make
sure that nothing remains in the holes.
Warning: Wear eye protection
when using compressed air!
19Remove the rear cover from the cylinder
head. Clean the gasket surface and refit the
cover with a new gasket (see illustration).
Place the side of the gasket with the sealer
bead against the cylinder head, do not use
sealant on this gasket.
20Fabricate two alignment studs from the
old head bolts. Cut off the heads, then slot the
ends with a hacksaw (see illustration). New
cylinder head bolts must be used when
refitting the head.
Engine in-car repair procedures 2A•13
2A
11.19 Remove the rear cover from the
cylinder head, clean the gasket surfaces
and refit the cover with a new gasket
(arrowed) - note that the printed-on sealer
bead is placed against the cylinder head11.20 Fabricate two alignment studs from
old cylinder head bolts and refit them in
the engine block - after the cylinder head
is installed, remove the two studs
3261 Jaguar XJ6 11.10 Disconnect the hoses and remove the bolts to separate the
coolant housing (arrowed) from the cylinder head
11.11 Remove the bolts (arrowed) securing the cylinder head
to the front cover

Inspection
8Clean and dry the pump body and both
rotors. Measure the outside diameter of the
outer rotor and thickness of both rotors.
9Place the outer rotor into the pump body
and use feeler gauges to measure the
clearance between the outer rotor and the
body (see illustration).
10Place a straightedge across the pump
body and measure between the straightedge
and the rotors to check the over-the-rotor
clearance (see illustration). Compare your
measurements to this Chapter’s Specifications
and renew the oil pump if any are beyond the
maximum allowable.
11Remove the oil pressure relief valve cap.
Remove and clean the relief valve components
(see illustration).
12Clean all components with solvent and
inspect them for wear and damage. If
excessive wear, damage or if any clearance is
beyond the Specifications, renew the entire
pump as an assembly.
13Check the oil pressure relief valve piston
sliding surface and valve spring. If either the
spring or the valve is damaged, they must be
renewed as a set.
Refitting
14Lubricate the drive and driven rotors with
clean engine oil and place them in the casewith the marks facing out. Apply a thin coat
of anaerobic sealant (Loctite 510 or 518) to
the gasket flange and refit the cover (see
illustration).
15Lubricate the oil pressure relief valve
piston with clean engine oil and refit the valve
components into the oil pump body (see
illustration 13.11).
16Apply a thin coat of anaerobic sealant
(Loctite 510 or 518) to the oil pump-to-engine
block-mounting surface, position the oil pump
body against the engine block and refit the
mounting bolts, tightening the bolts to the
torque listed in this Chapter’s Specifications.
Follow a criss-cross pattern when tightening
the bolts to avoid warping the oil pump body.
17If using the original oil pump, refit the
original sprocket shim pack (see illustration).
If a new pump is installed, start off with a
0.38 mm (0.015-inch) thick shim pack, refit the
drive sprocket and align the sprocket as
follows.
18Use a straightedge to check the alignment
of the oil pump sprocket with the crankshaft
sprocket (see illustration). If they are not
aligned, increase or decrease the shim pack at
the oil pump sprocket until alignment is correct,
then secure the oil pump sprocket bolts by
bending up the sheetmetal tabs. Note:You
may be able to use all or part of the original
shim pack from the original oil pump (if a new
pump is being fitted). If required, shims areavailable in 0.127 mm (0.005 inch), 0.254 mm
(0.010 inch) and 0.508 mm (0.020 inch) sizes.
19Fit new O-rings to each end of the transfer
tubes and refit the tubes into the transfer
housing. Note:Use petroleum jelly to lubricate
the O-rings.
20Apply a thin coat of RTV sealant to the
engine block-mounting surface of the transfer
housing. Lift the transfer housing and tubes
into place and push the front of the tubes
in the back of the oil pump, until you can start
the transfer housing-to-engine block bolts.
Tighten the bolts to the torque listed in this
Chapter’s Specifications.
21Refit the remaining parts in the reverse
order of removal.
22Add oil, start the engine and check for oil
pressure and leaks.
23Recheck the engine oil level.
14 Driveplate-
removal and refitting
4
Removal
1Raise the car and support it securely on
axle stands, then refer to Chapter 7 and
remove the transmission. If it’s leaking, now
would be a very good time to renew the front
pump seal/O-ring.
2A•16 Engine in-car repair procedures
13.9 Measure the outer rotor-to-body
clearance with feeler gauges (arrowed)13.10 With a straightedge held tight to the
pump surface, measure the clearance over
the rotors with feeler gauges13.11 Oil pressure relief valve components
A Relief valve cap
B TubeC Spring
D Valve
13.14 Apply a thin coat anaerobic sealant
(Loctite 510 or 518) to the pump cover
sealing surface
13.17 Refit the original shim pack
(arrowed) if the original pump is being
used - if a new pump is being installed,
refit a 0.38 mm (0.015-inch) shim pack
3261 Jaguar XJ6
13.18 Check the oil pump and crankshaft
sprocket alignment with a straightedge -
add or subtract shims until the sprockets
are aligned for smooth chain operation