Peugeot 405. Manual - part 18

66 Slide on the crankshaft sprocket, aligning
its slot with the Woodruff key.
67 Thoroughly clean the threads of the
sprocket retaining bolt, then apply a coat of
locking compound to the threads of the bolt.
68 Refit the crankshaft sprocket retaining
bolt and washer. Tighten the bolt to the
specified torque, whilst preventing crankshaft
rotation using the method employed on
removal.
69 Refit the locking pin to the crankshaft
sprocket, and check that both the camshaft
sprocket locking pins are still in position.
70 Relocate the timing belt on the crankshaft
sprocket, and tension the timing belt as
described in Section 7.
71 Once the belt is correctly tensioned, refit
the timing belt cover (see Section 6).

Tensioner assembly - early (pre-1992)
1580 cc and 1905 cc 8-valve models
with a semi-automatic belt tensioner

72 Manoeuvre the tensioner pulley and
backplate assembly into position behind the
timing belt, and locate it on the mounting
studs.
73 Insert the tensioner cam spindle through
the backplate from the front of the block, and
refit its washer and locknut, tightening it by
hand only at this stage.
74 Fit the spring to the inside of the spring
cover. Compress the spring, and slide the
spring cover onto the two mounting studs,
ensuring that the spring end is correctly
located behind the backplate tang.
75 Refit the tensioner mounting nuts and
washers, tightening them by hand only. Check
that the tensioner is forced against the timing
belt by spring pressure, and is free to move
smoothly and easily.
76 Ensure that the “front run” of the belt is
taut - ie, that any slack is on the pulley side of
the belt. Check that the belt is centrally
located on all its sprockets, then release the
tensioner assembly and allow it to tension the
belt.
77 Tension the timing belt, and check the
valve timing as described in Section 7.
78 With the belt correctly tensioned, and the
tensioner retaining nuts and locknut tightened
to the specified torque setting, refit the timing
belt covers as described in Section 6.
Reconnect the battery on completion.

Tensioner pulley - later (1992-on) 
1580 cc and 1905 cc models with a
manually-adjusted belt tensioner
pulley, and all 1761 cc and 
1998 cc 8-valve models

79 Refit the tensioner pulley to its mounting
stud, and fit the retaining bolt.
80 Ensure that the “front run” of the belt is
taut - ie, that any slack is on the pulley side of
the belt. Check that the belt is centrally
located on all its sprockets. Rotate the pulley
anti-clockwise to remove all free play from the
timing belt, and securely tighten the pulley
retaining nut.
81 Tension the belt (see Section 7).

82 Once the belt is correctly tensioned, refit
the timing belt covers as described in 
Section 6.

Tensioner pulleys - 1905 cc 16-valve
models

83 Refit the tensioner pulleys to their studs,
and fit the retaining bolts. Tighten the bolts
finger-tight only, so that both tensioners are
free to pivot.
84 Tension the timing belt (see Section 7).
85 Once the belt is correctly tensioned, refit
the timing belt cover (see Section 6).

Tensioner pulleys - 1998 cc 16-valve
models

86 Refit the rear tensioner pulley to its
mounting stud, and fit the retaining bolt. Align
the front pulley backplate with its holes, and
refit both its retaining bolts. Tighten all
retaining bolts finger-tight only, so that both
tensioners are free to pivot.
87 Tension the timing belt (see Section 7).
88 Once the belt is correctly tensioned, refit
the timing belt cover (see Section 6).

9

Camshaft oil seal(s) - renewal

4

Note: If the camshaft oil seal is to be renewed
with the timing belt still in place, check first
that the belt is free from oil contamination.
(Renew the belt as a matter of course if signs
of oil contamination are found; see Section 7.)
Cover the belt, to protect it from
contamination by oil while work is in progress.
If the timing belt is removed, ensure that all
traces of oil are removed from the area before
the belt is refitted.
1 Remove the camshaft sprocket(s) as
described in Section 8.
2 Punch or drill two small holes opposite
each other in the oil seal. Screw a self-tapping
screw into each, and pull on the screws with
pliers to extract the seal.
3 Clean the seal housing, and polish off any
burrs or raised edges, which may have
caused the seal to fail in the first place.
4 Lubricate the lips of the new seal with clean
engine oil, and drive it into position until it
seats on its locating shoulder. Use a suitable
tubular drift, such as a socket, which bears
only on the hard outer edge of the seal. Take
care not to damage the seal lips during fitting.
Note that the seal lips should face inwards.
5 Refit the camshaft sprocket(s) as described
in Section 8.

10 Camshaft and followers -

removal, inspection and
refitting

4

Removal

1 Remove the battery and its mounting tray
as described in Chapter 5A.

2 Remove the cylinder head cover and gasket
as described in Section 4.

1905 cc 16-valve models

3 Unbolt the plastic cover from over the
power steering pump drive pulley.
4 Disconnect the drivebelt from the power
steering drive pulley with reference to 
Chapter 1.
5 Unscrew the bolt and remove the pulley
from the end of the exhaust camshaft.
6 Remove both camshaft sprockets as
described in Section 8.
7 Remove the distributor cap and rotor arm
with reference to Chapter 5A. 
8 Unbolt and remove the rotor arm support
and the sealing disc.
9 Unbolt the inner timing belt cover from the
side of the cylinder head.
10 Carefully ease the oil supply pipe out from
the top of the camshaft bearing caps, and
remove it. Note the O-ring seals fitted to each
of the pipe unions.
11 Turn each camshaft so that the sprocket
key grooves are approximately at the 3
o’clock position.
12 Evenly and progressively slacken the
camshaft bearing cap retaining screws by one
turn at a time. This will relieve the valve spring
pressure on the bearing caps gradually and
evenly. Once the pressure has been relieved,
the bolts can be fully unscrewed and
removed.
13 Lift off the bearing caps, noting the
correct fitted location of the locating dowels.
If the dowels are a loose fit, remove them and
store them with the bearing caps for safe-
keeping.
14 Lift the camshafts out of the cylinder
head, and slide the oil seals off the camshaft
ends. Identify each camshaft for position - on
early models the inlet camshaft is identified by
the distributor drive keyway.
15 Obtain sixteen small, clean plastic
containers, and number them 1 to 16. Using a
rubber sucker, withdraw each cam follower in
turn, invert it to prevent oil loss, and place it in
its respective container. The container should
then be filled with clean engine oil. Do not
interchange the cam followers, or the rate of
wear will be much-increased. Do not allow
them to lose oil, or the hydraulic tappet
mechanism will take a long time to refill with
oil on restarting the engine, resulting in
incorrect valve clearances.

1998 cc 16-valve models

16 Remove both camshaft sprockets as
described in Section 8. Where necessary also
remove the vacuum pump from the left-hand
end of the cylinder head.
17 Undo the six bolts securing the inner
timing belt cover to the side of the cylinder
head, and remove the cover from the engine.
18 Carefully ease the oil supply pipe out from
the top of the camshaft bearing caps, and
remove it. Note the O-ring seals fitted to each
of the pipe unions.
19 The camshaft bearing caps should be

2B•14 XU engine in-car repair procedures

numbered 1 to 5, number 1 being at the
transmission end of the engine. If not, make
identification marks on the caps, using white
paint or a suitable marker pen.
20 Working in the reverse of the sequence
shown in illustration 10.54, evenly and
progressively slacken the camshaft bearing
cap retaining screws by one turn at a time.
This will relieve the valve spring pressure on
the bearing caps gradually and evenly. Once
the pressure has been relieved, the bolts can
be fully unscrewed and removed.
21 Lift off the bearing caps, noting the
correct fitted location of the locating dowels.
If the dowels are a loose fit, remove them and
store them with the bearing caps for safe-
keeping.
22 Lift the camshafts out of the cylinder
head, and slide the oil seals off the camshaft
ends. The inlet camshaft can be identified by
the braking system vacuum pump drive slot in
its left-hand end; therefore, there is no need to
mark the camshafts for identification.
23 Obtain sixteen small, clean plastic
containers, and number them 1 to 16. Using a
rubber sucker, withdraw each cam follower in
turn, invert it to prevent oil loss, and place it in
its respective container. The container should
then be filled with clean engine oil. Do not
interchange the cam followers, or the rate of
wear will be much-increased. Do not allow
them to lose oil, or the hydraulic tappet
mechanism will take a long time to refill with
oil on restarting the engine, resulting in
incorrect valve clearances.

All other models

24 Remove the camshaft sprocket as
described in Section 8.
25 On models with a distributor, remove the
distributor as described in Chapter 5. Make
sure the recessed socket-headed screw is
removed from the distributor housing.
26 On models with a carburettor, remove the
fuel pump as described in Chapter 4.
27 On models with a static (distributorless)
ignition system, remove the ignition HT coil as
described in Chapter 5.
28 With the distributor or coil removed (as
applicable), slacken the upper bolt securing
the thermostat housing to the left-hand end of
the cylinder head. Remove the bolt, along with

its sealing washer. This is necessary since the
bolt screws into the left-hand (No 1) camshaft
bearing cap.
29 Carefully ease the oil supply pipe out from
the top of the camshaft bearing caps, and
remove it. Note the O-ring seals fitted to each
of the pipe unions on later models.
30 The camshaft bearing caps should be
numbered 1 to 5, number 1 being at the
transmission end of the engine. If not, make
identification marks on the caps, using white
paint or a suitable marker pen. Also mark
each cap in some way to indicate its correct
fitted orientation. This will avoid the possibility
of installing the caps the wrong way around
on refitting.
31 Evenly and progressively slacken the
camshaft bearing cap retaining nuts by one
turn at a time. This will relieve the valve spring
pressure on the bearing caps gradually and
evenly. Once the pressure has been relieved,
the nuts can be fully unscrewed and removed
(see illustration).
32 Note the correct fitted orientation of the
bearing caps, then remove them from cylinder
head (see illustration).
33 Lift the camshaft away from the cylinder
head, and slide the oil seal off the camshaft
end (see illustration).
34 Obtain eight small, clean plastic
containers, and number them 1 to 8;
alternatively, divide a larger container into
eight compartments. Using a rubber sucker,
withdraw each follower in turn, and place it in
its respective container. Do not interchange
the cam followers, or the rate of wear will be
much-increased. If necessary, also remove
the shim from the top of the valve stem, and
store it with its respective follower. Note that
the shim may stick to the inside of the follower
as it is withdrawn. If this happens, take care
not to allow it to drop out as the follower is
removed.

Inspection

35 Examine the camshaft bearing surfaces
and cam lobes for signs of wear ridges and
scoring. Renew the camshaft if any of these
conditions are apparent. Examine the
condition of the bearing surfaces, both on the
camshaft journals and in the cylinder
head/bearing caps. If the head bearing

surfaces are worn excessively, the cylinder
head will need to be renewed. If suitable
measuring equipment is available, camshaft
bearing journal wear can be checked by direct
measurement (where the necessary specifica-
tions have been quoted by Peugeot), noting
that No 1 journal is at the transmission end of
the head.
36 Examine the cam follower bearing
surfaces which contact the camshaft lobes for
wear ridges and scoring. Renew any follower
on which these conditions are apparent. If a
follower bearing surface is badly scored, also
examine the corresponding lobe on the
camshaft for wear, as it is likely that both will
be worn. Renew worn components as
necessary.
37 On 16-valve models, if the engine’s valve
clearances have sounded noisy, particularly if
the noise persists after initial start-up from
cold, there is reason to suspect a faulty
hydraulic tappet mechanism. Only a good
mechanic experienced in these engines can
tell whether the noise level is typical, or if
renewal of one or more of the tappets is
warranted. If a faulty hydraulic tappet is
diagnosed and the engine’s service history is
unknown, it is always worth trying the effect of
renewing the engine oil and filter before going
to the expense of renewing any of the cam
followers. Use only good-quality engine oil of
the recommended viscosity and specification
(Chapter 1). It is not possible to overhaul the
hydraulic tappet mechanism, so if any
tappet’s operation is faulty, it must be
renewed.
38 On earlier 1580 cc and 1905 cc models,
inspect the camshaft thrust fork (fitted to the
side of No 5 camshaft bearing cap) for signs
of wear or scoring, and if necessary renew it
(see illustrations). The fork is retained by a
single bolt; on refitting, ensure that the bolt is
securely tightened. On later models, the thrust
fork is no longer fitted, and the camshaft
endfloat is controlled by the camshaft bearing
cap.

Refitting

1905 cc 16-valve models

39 Liberally oil the cylinder head cam
follower bores and the followers. Note that, if

XU engine in-car repair procedures  2B•15

10.33  . . . then lift the camshaft away from

the cylinder head

10.32  . . . and remove the camshaft

bearing caps . . .

2B

10.31  Working as described in the text,

unscrew the retaining nuts . . .

new followers are being fitted, they must be
charged with oil before installation by placing
them in a bath of clean engine oil and
“working” them. Carefully refit the followers to
the cylinder head, ensuring that each follower
is refitted to its original bore, where
applicable. Some care will be required to
enter the followers squarely into their bores.
40 Liberally oil the camshaft bearings and
lobes, then refit the camshafts to the cylinder
head. Temporarily refit the Woodruff keys and
sprockets to the end of each camshaft. Set
each camshaft so that the sprocket key
grooves are approximately at the 3 o’clock
position. Also ensure that the crankshaft is
still locked in position (see Section 3).
41 Ensure that the bearing cap locating
dowels are pressed firmly into their recesses.
Check that the mating surfaces are
completely clean, unmarked and free from oil
then apply jointing compound to the contact
surfaces of Nos 1 and 5 caps.. Refit the
bearing caps, using the identification marks
noted on removal to ensure that each is
installed correctly and in its original location.
42 Working in the sequence shown,
progressively tighten the camshaft bearing
cap bolts by one turn at a time, until the caps
touch the cylinder head evenly. Go round
again, working in the same sequence, and
tighten all the bolts to the specified torque
setting. Work only as described, to impose
the pressure of the valve springs gradually
and evenly on the bearing caps.
43 Examine the oil supply pipe union O-rings
for signs of damage or deterioration, and
renew as necessary. Check that the supply
pipe oil spray holes are clear, unblocking
them with a pin if necessary. Apply a smear of
clean engine oil to the O-rings. Ease the pipe
assembly into position in the top of the
bearing caps, taking great care not to
displace the O-rings.
44 Refit the inner timing belt cover to the side
of the cylinder head, and tighten its retaining
bolts to the specified torque.
45 Fit two new camshaft oil seals using the
information given in Section 7.
46 Where applicable, refit the distributor
rotor arm support and sealing disc, rotor arm
and distributor cap - refer to Chapter 5A.
47 Refit the camshaft sprockets as described
in Section 8.

48 Refit the power steering pulley to the end
of the exhaust camshaft and tighten the
retaining bolt, then refit the drivebelt with
reference to Chapter 1.
49 Refit the plastic cover over the power
steering pump drive pulley.
50 Refit the cylinder head cover as described
in Section 4, and the battery and mounting
tray as described in Chapter 5A.

1998 cc 16-valve models

51 Liberally oil the cylinder head cam
follower bores and the followers. Note that, if
new followers are being fitted, they must be
charged with oil before installation by placing
them in a bath of clean engine oil and
“working” them. Carefully refit the followers to
the cylinder head, ensuring that each follower
is refitted to its original bore, where
applicable. Some care will be required to
enter the followers squarely into their bores.
52 Liberally oil the camshaft bearings and
lobes, then refit the camshafts to the cylinder
head. Temporarily refit the Woodruff keys and
sprockets to the end of each camshaft. Set
each camshaft so that its sprocket timing hole
is aligned with the corresponding cutout in the
cylinder head. Also ensure that the crankshaft
is still locked in position (see Section 3).
53 Ensure that the bearing cap locating
dowels are pressed firmly into their recesses.
Check that the mating surfaces are
completely clean, unmarked and free from oil.
Refit the bearing caps, using the identification
marks noted on removal to ensure that each is
installed correctly and in its original location.

54 Working in the sequence shown,
progressively tighten the camshaft bearing
cap bolts by one turn at a time, until the caps
touch the cylinder head evenly. Go round
again, working in the same sequence, and
tighten all the bolts to the specified torque
setting  (see illustration). Work only as
described, to impose the pressure of the valve
springs gradually and evenly on the bearing
caps.
55 Examine the oil supply pipe union O-rings
for signs of damage or deterioration, and
renew as necessary. Check that the supply
pipe oil spray holes are clear, unblocking
them with a pin if necessary. Apply a smear of
clean engine oil to the O-rings. Ease the pipe
assembly into position in the top of the
bearing caps, taking great care not to
displace the O-rings (see illustration).
56 Refit the inner timing belt cover to the side
of the cylinder head, and tighten its retaining
bolts to the specified torque.
57 Fit two new camshaft oil seals using the
information given in Section 7, then refit the
camshaft sprockets as described in Section 8.
Where necessary refit the vacuum pump to
the left-hand end of the cylinder head.
58 Refit the cylinder head cover as described
in Section 4, and reconnect the battery
negative terminal.

All other models

59 Where removed, refit each shim to the top
of its original valve stem. Do not interchange
the shims, as this will upset the valve
clearances (see Section 11).
60 Liberally oil the cylinder head cam
follower bores and the followers. Carefully
refit the followers to the cylinder head,
ensuring that each follower is refitted to its
original bore. Some care will be required to
enter the followers squarely into their bores.
61 Liberally oil the camshaft bearings and
lobes, then refit the camshaft to the cylinder
head. Temporarily refit the sprocket to the end
of the shaft, and position it so that the
sprocket timing hole is aligned with the
corresponding cutout in the cylinder head.
Also ensure that the crankshaft is still locked
in position (see Section 3).
62 Ensure that the bearing cap and head
mating surfaces are completely clean,

10.55  Take care not to displace the 

O-rings when refitting the oil supply pipe

to the camshaft bearing caps

2B•16 XU engine in-car repair procedures

10.38a  On early 1580 cc and 1905 cc

models, slacken the retaining bolt . . .

10.54  Camshaft bearing cap bolt

tightening sequence - 

1998 cc 16-valve models

10.38b  . . . and remove the camshaft

thrust fork from the bearing cap

unmarked, and free from oil. Refit the bearing
caps, using the identification marks noted on
removal to ensure that each is installed
correctly and in its original location.
63 Evenly and progressively tighten the
camshaft bearing cap nuts by one turn at a
time until the caps touch the cylinder head.
Then go round again and tighten all the nuts
to the specified torque setting. Work only as
described, to impose the pressure of the valve
springs gradually and evenly on the bearing
caps.
64 Refit the oil supply pipe to the top of the
bearing caps. Note that there are no seals
fitted to the pipe fittings on early models,
however later versions are fitted with seals.
Where applicable, examine the oil supply pipe
union O-rings for signs of damage or
deterioration, and renew as necessary. Apply
a smear of clean engine oil to the O-rings
before refitting the pipe (see illustration).
65 Examine the sealing washer for signs of
damage or deterioration, and renew it if
necessary. Refit the upper retaining bolt to the
thermostat housing, tightening it to the
specified torque setting.
66 On models with a distributor, refit the
distributor as described in Chapter 5.
67 On models with a static (distributorless)
ignition system, refit the ignition HT coil as
described in Chapter 5.
68 On models with a carburettor, refit the fuel
pump with reference to Chapter 4.
69 Fit a new camshaft oil seal, using the
information given in Section 9, then refit the
camshaft sprocket as described in Section 8.
70 Refit the cylinder head cover as described
in Section 4, then refit the battery and
mounting tray with reference to Chapter 5A.

11 Valve clearances - checking

and adjustment

3

Checking

16-valve models

1 On 1905 cc and 1998 cc 16-valve models,
the valve clearances are automatically
adjusted by the hydraulic tappet mechanism

fitted to each cam follower. Therefore it is not
necessary, or indeed possible, to check or
adjust the valve clearances manually. If the
valve gear has become noisy, a faulty tappet
mechanism should be suspected. Refer to
Section 10 for further information.

All other models

2 On these models, the importance of having
the valve clearances correctly adjusted
cannot be overstressed, as they vitally affect
the performance of the engine. Checking
should not be regarded as a routine operation,
however. It should only be necessary when
the valve gear has become noisy, after engine
overhaul, or when trying to trace the cause of
power loss. The clearances are checked as
follows. The engine must be cold for the
check to be accurate.
3 Apply the handbrake, then jack up the front
of the car and support it on axle stands (see
“Jacking and Vehicle Support”). Remove the
right-hand front roadwheel.
4 From underneath the front of the car, prise
out the two retaining clips, and remove the
plastic cover from the wing valance to gain
access to the crankshaft sprocket bolt. Where
necessary, unclip the coolant hoses from the
bracket to improve access further.
5 The engine can now be turned over using a
suitable socket and extension bar fitted to the
crankshaft pulley bolt.
6 Remove the cylinder head cover as
described in Section 4.
7 Draw the outline of the engine on a piece of
paper, numbering the cylinders 1 to 4, with 
No 1 cylinder at the transmission end of the
engine. Show the position of each valve,
together with the specified valve clearance
(see paragraph 11). Above each valve, draw
two lines for noting (1) the actual clearance
and (2) the amount of adjustment required
(see illustration).
8 Turn the crankshaft until the inlet valve of
No 1 cylinder (nearest the transmission end) is

fully closed, with the tip of the cam facing
directly away from the cam follower.
9 Using feeler blades, measure the clearance
between the base of the cam and the follower
(see illustration). Record the clearance on
line (1).
10 Repeat the measurement for the other
seven valves, turning the crankshaft as
necessary so that the cam lobe in question is
always facing directly away from the relevant
follower.
11 Calculate the difference between each
measured clearance and the desired value,
and record it on line (2). Since the clearance is
different for inlet and exhaust valves, make
sure that you are aware which valve you are
dealing with. The valve sequence from either
end of the engine is:

Ex - In - In - Ex - Ex - In - In - Ex

12 If all the clearances are within tolerance,
refit the cylinder head cover with reference to
Section 4. Clip the coolant hoses into position
(if removed) and refit the plastic cover to the
wing valance. Refit the roadwheel, and lower
the vehicle to the ground.
13 If any clearance measured is outside the
specified tolerance, adjustment must be
carried out as described in the following
paragraphs.

Adjustment

16-valve models

14 See paragraph 1.

All other models

15 Remove the camshaft as described in
Section 10.
16 Withdraw the first follower from the
cylinder head, and recover the shim from the
top of the valve stem. Note that the shim may
stick to the inside of the follower as it is
withdrawn. If this happens, take care not to
allow it to drop out as the follower is removed.
Remove all traces of oil from the shim, and
measure its thickness with a micrometer (see
illustrations). The shims usually carry
thickness markings, but wear may have
reduced the original thickness.
17 Refer to the clearance recorded for the
valve concerned. If the clearance was more
than that specified, the shim thickness must
be increased by the difference recorded (2). If

XU engine in-car repair procedures  2B•17

11.7  Example of valve shim thickness

calculation

I  Inlet
E  Exhaust
1  Measured clearance
2  Difference between 1 and 3
3  Specified clearance
4  Thickness of original shim fitted
5  Thickness of new shim required

11.9  Measuring a valve clearance 

using a feeler blade

10.64  Early supply pipe (A) without seals

and later pipe (B) with seals

2B