Peugeot 405. Manual - part 25

drive chain) at the same time. If the new
bearing arrangement is to be used without
uprating the lubrication system, Peugeot state
that  Blue (Class A) lower bearing shells should
be fitted. Refer to your Peugeot dealer for
further information.
17 Since there are no bearing identification
marks, the relevant main bearing shell grade
must be selected by measuring the main
bearing running clearance.

Main bearing 
running clearance check

TU series engine

18 On early engines, if the modified bearing
shells are to be fitted, obtain a set of new
black (Class B) upper bearing shells and new
blue (Class A) lower bearing shells. On later
(February 1992-on) engines where the
modified bearing shells are already fitted, the
running clearance check can be carried out
using the original bearing shells. However, it is
preferable to use a new set, since the results
obtained will be more conclusive.
19 Clean the backs of the bearing shells, and
the bearing locations in both the cylinder
block/crankcase and the main bearing ladder.
20 Press the bearing shells into their
locations, ensuring that the tab on each shell
engages in the notch in the cylinder

block/crankcase or main bearing ladder
location. Take care not to touch any shell’s
bearing surface with your fingers. Note that
the grooved bearing shells, both upper and
lower, are fitted to Nos 2 and 4 main bearings
(see illustration). If the original bearing shells
are being used for the check, ensure that they
are refitted in their original locations. The
clearance can be checked in either of two
ways.
21 One method (which will be difficult to
achieve without a range of internal
micrometers or internal/external expanding
calipers) is to refit the main bearing ladder
casting to the cylinder block/crankcase, with
the bearing shells in place. With the casting
retaining bolts correctly tightened, measure
the internal diameter of each assembled pair
of bearing shells. If the diameter of each
corresponding crankshaft journal is measured
and then subtracted from the bearing internal
diameter, the result will be the main bearing
running clearance.
22 The second (and more accurate) method
is to use a product known as “Plastigauge”.
This consists of a fine thread of perfectly-
round plastic, which is compressed between
the bearing shell and the journal. When the
shell is removed, the plastic is deformed, and
can be measured with a special card gauge

supplied with the kit. The running clearance is
determined from this gauge. Plastigauge
should be available from your Peugeot dealer,
otherwise enquiries at one of the larger
specialist motor factors should produce the
name of a stockist in your area. The
procedure for using Plastigauge is as follows.
23 With the main bearing upper shells in
place, carefully lay the crankshaft in position.
Do not use any lubricant; the crankshaft
journals and bearing shells must be perfectly
clean and dry.
24 Cut several lengths of the appropriate-
size Plastigauge (they should be slightly
shorter than the width of the main bearings),
and place one length on each crankshaft
journal axis (see illustration).
25 With the main bearing lower shells in
position, refit the main bearing ladder casting,
tightening its retaining bolts as described in
paragraph 45. Take care not to disturb the
Plastigauge, and do not rotate the crankshaft
at any time during this operation.
26 Remove the main bearing ladder casting,
again taking great care not to disturb the
Plastigauge or rotate the crankshaft.
27 Compare the width of the crushed
Plastigauge on each journal to the scale
printed on the Plastigauge envelope, to obtain
the main bearing running clearance (see
illustration). Compare the clearance
measured with that given in the Specifications
at the start of this Chapter.
28 If the clearance is significantly different
from that expected, the bearing shells may be
the wrong size (or excessively worn, if the
original shells are being re-used). Before
deciding that different-size shells are required,
make sure that no dirt or oil was trapped
between the bearing shells and the caps or
block when the clearance was measured. If
the Plastigauge was wider at one end than at
the other, the crankshaft journal may be
tapered.
29 If the clearance is not as specified, use
the reading obtained, along with the shell
thicknesses quoted above, to calculate the
necessary grade of bearing shells required.
When calculating the bearing clearance
required, bear in mind that it is always better
to have the running clearance towards the

2C•18 Engine removal and overhaul

18.14  Main bearing shell selection chart, for use with XU series engines - 

see text for further information

18.20  On TU series engines, note that the

grooved bearing shells are fitted to 

Nos 2 and 4 main bearing journals

18.27  Measuring the width of the

deformed Plastigauge using the scale on

the card provided

18.24  Plastigauge in place on a crankshaft

main bearing journal

lower end of the specified range, to allow for
wear in use.
30 Where necessary, obtain the required
grades of bearing shell, and repeat the
running clearance checking procedure as
described above.
31 On completion, carefully scrape away all
traces of the Plastigauge material from the
crankshaft and bearing shells. Use your
fingernail, or a wooden or plastic scraper
which is unlikely to score the bearing
surfaces.

XU series engine

32 On early engines, if the later bearing shells
are to be fitted, obtain a set of new upper
bearing shells, and new green or grey (as
applicable) lower bearing shells (see
paragraph 10). On later engines where the
modified bearing shells are already fitted, the
running clearance check can be carried out
using the original bearing shells. However, it is
preferable to use a new set, since the results
obtained will be more conclusive.
33 Clean the backs of the bearing shells, and
the bearing locations in both the cylinder
block/crankcase and the main bearing caps.
34 Press the bearing shells into their
locations, ensuring that the tab on each shell
engages in the notch in the cylinder
block/crankcase or bearing cap. Take care
not to touch any shell’s bearing surface with
your fingers. Note that the upper bearing
shells all have a grooved bearing surface,
whereas the lower shells have a plain bearing
surface  (see illustration). If the original

bearing shells are being used for the check,
ensure that they are refitted in their original
locations.
35 The clearance can be checked in two ways.
36 One method (which will be difficult to
achieve without a range of internal
micrometers or internal/external expanding
calipers) is to refit the main bearing caps to
the cylinder block/crankcase, with bearing
shells in place. With the cap retaining bolts
tightened to the specified torque, measure the
internal diameter of each assembled pair of
bearing shells. If the diameter of each
corresponding crankshaft journal is measured
and then subtracted from the bearing internal
diameter, the result will be the main bearing
running clearance.
37 The second, and more accurate, method
is to use Plastigauge. The method is as
described above in paragraphs 17 to 26,
substituting “main bearing caps” for all
references to the main bearing ladder casting.
38 Note that Peugeot do not specify a main
bearing running clearance for 1905 cc
engines. The figure given in the Specifications
is a guide figure which is typical for this type
of engine. On these engines, therefore, always
refer to your Peugeot dealer for details of the
exact running clearance before condemning
the components concerned.

Final crankshaft refitting

TU aluminium block engines

39 Carefully lift the crankshaft out of the
cylinder block once more.

40 Using a little grease, stick the upper
thrustwashers to each side of the No 2 main
bearing upper location; ensure that the oilway
grooves on each thrustwasher face outwards
(away from the cylinder block) (see
illustration).
41 Place the bearing shells in their locations
as described earlier. If new shells are being
fitted, ensure that all traces of protective
grease are cleaned off using paraffin. Wipe
dry the shells and connecting rods with a lint-
free cloth. Liberally lubricate each bearing
shell in the cylinder block/crankcase with
clean engine oil (see illustration).
42 Refit the Woodruff key, then slide on the
oil pump drive sprocket, and locate the drive
chain on the sprocket (see illustration).
Lower the crankshaft into position so that Nos
2 and 3 cylinder crankpins are at TDC; Nos 1
and 4 cylinder crankpins will be at BDC, ready
for fitting No 1 piston. Check the crankshaft
endfloat as described in Section 13.
43 Thoroughly degrease the mating surfaces
of the cylinder block/crankcase and the main
bearing ladder. Apply a thin bead of suitable
sealant to the cylinder block/crankcase
mating surface of the main bearing ladder
casting, then spread to an even film (see
illustration).
44 Lubricate the lower bearing shells with
clean engine oil, then refit the main bearing
ladder, ensuring that the shells are not
displaced, and that the locating dowels
engage correctly (see illustration).
45 Install the ten 11 mm main bearing ladder

Engine removal and overhaul  2C•19

18.41  Ensure each bearing shell tab

(arrowed) is correctly located, 

and apply clean engine oil

18.44  . . . then lower the main bearing

ladder into position

18.43  Apply a film of suitable sealant to

cylinder block/crankcase mating surface . . .

18.42  Refitting the oil pump drive chain

and sprocket - TU aluminium block engine

18.40  Refitting a crankshaft thrustwasher

- TU series aluminium block engine

18.34  On XU engines, all the lower shells

have a plain bearing surface. Ensure tab

(arrowed) is correctly located in the cap

2C

retaining bolts, and tighten them all by hand
only. Working progressively outwards from
the centre bolts, tighten the ten bolts, by a
turn at a time, to the specified Stage 1 torque
wrench setting. Once all the bolts have been
tightened to the Stage 1 setting, angle-tighten
the bolts through the specified Stage 2 angle
using a socket and extension bar. It is
recommended that an angle-measuring
gauge is used during this stage of the
tightening, to ensure accuracy (see
illustrations). If a gauge is not available, use a
dab of white paint to make alignment marks
between the bolt head and casting prior to
tightening; the marks can then be used to
check that the bolt has been rotated
sufficiently during tightening.
46 Refit all the 6 mm bolts securing the main
bearing ladder to the base of the cylinder
block, and tighten them to the specified
torque. Check that the crankshaft rotates
freely.
47 Refit the piston/connecting rod
assemblies to the crankshaft as described in
Section 18.
48 Ensuring that the drive chain is correctly
located on the sprocket, refit the oil pump and
sump as described in Part A of this Chapter.
49 Fit two new crankshaft oil seals as
described in Part A.
50 Refit the flywheel as described in Part A of
this Chapter.
51 Where removed, refit the cylinder head as
described in Part A. Also refit the crankshaft
sprocket and timing belt as described in 
Part A.

TU series cast-iron block engine

52 Carefully lift the crankshaft out of the
cylinder block once more.
53 Using a little grease, stick the upper
thrustwashers to each side of No 2 main
bearing upper location. Ensure the oilway
grooves on each thrustwasher face outwards
(away from the cylinder block) (see illustration).
54 Place the bearing shells in their locations
as described earlier (see illustration). If new
shells are being fitted, ensure that all traces of
protective grease are cleaned off using
paraffin. Wipe dry the shells and connecting
rods with a lint-free cloth. Liberally lubricate
each bearing shell in the cylinder block/
crankcase and cap with clean engine oil.
55 Lower the crankshaft into position so that
Nos 2 and 3 cylinder crankpins are at TDC;
Nos 1 and 4 cylinder crankpins will be at BDC,
ready for fitting No 1 piston. Check the
crankshaft endfloat, referring to Section 14.
56 Lubricate the lower bearing shells in the
main bearing caps with clean engine oil. Make
sure that the locating lugs on the shells
engage with the corresponding recesses in
the caps.
57 Fit the main bearing caps to their correct
locations, ensuring that they are fitted the
correct way round (the bearing shell lug
recesses in the block and caps must be on
the same side). Insert the bolts loosely.
58 Tighten the main bearing cap bolts to the
specified Stage 1 torque wrench setting.
Once all the bolts have been tightened to the
Stage 1 setting, angle-tighten the bolts
through the specified Stage 2 angle, using a
socket and extension bar. It is recommended

that an angle-measuring gauge is used during
this stage of the tightening, to ensure
accuracy. If a gauge is not available, use a
dab of white paint to make alignment marks
between the bolt head and casting prior to
tightening; the marks can then be used to
check that the bolt has been rotated
sufficiently during tightening.
59 Check that the crankshaft rotates freely.
60 Refit the piston/connecting rod
assemblies to the crankshaft as described in
Section 19.
61 Refit the Woodruff key to the crankshaft
groove, and slide on the oil pump drive
sprocket. Locate the drive chain on the
sprocket.
62 Ensure that the mating surfaces of front
oil seal housing and cylinder block are clean
and dry. Note the correct fitted depth of the
front oil seal then, using a large flat-bladed
screwdriver, lever the seal out of the housing.
63 Apply a smear of suitable sealant to the oil
seal housing mating surface, and make sure
that the locating dowels are in position. Slide
the housing over the end of the crankshaft,
and into position on the cylinder block.
Tighten the housing retaining bolts securely.
64 Repeat the operations in paragraphs 62
and 63, and fit the rear oil seal housing.
65 Fit a new front and rear crankshaft oil seal
as described in Part A of this Chapter.
66 Ensuring that the chain is correctly
located on the drive sprocket, refit the oil
pump and sump as described in Part A of this
Chapter.
67 Refit the flywheel (Part A of this Chapter).
68 Where removed, refit the cylinder head
and install the crankshaft sprocket and timing
belt - see the relevant Sections of Part A.

XU series engines

69 Carry out the operations described above
in paragraphs 52 to 56.
70 Fit main bearing caps Nos 2 to 5 to their
correct locations, ensuring that they are fitted
the correct way round (the bearing shell tab
recesses in the block and caps must be on
the same side). Insert the bolts/nuts,
tightening them only loosely at this stage.
71 Apply a small amount of sealant to No 1
main bearing cap face mating on the cylinder
block, around the sealing strip holes (see
illustration).

2C•20 Engine removal and overhaul

18.45a  Tighten ten 11 mm main bearing

bolts to the stage 1 torque setting . . .

18.53  Fitting a thrustwasher to 

No 2 main bearing upper location

18.71  Applying sealant to the cylinder

block No 1 main bearing cap mating face

18.54  Ensure tab (arrowed) is located in

the cap when fitting the bearing shells

18.45b  . . . then angle-tighten them
through the specified stage 2 angle

72 Locate the tab of each sealing strip over
the pins on the base of No 1 bearing cap, and
press the strips into the bearing cap grooves.
It is now necessary to obtain two thin metal
strips, of 0.25 mm thickness or less, in order
to prevent the strips moving when the cap is
being fitted. Peugeot garages use the tool
shown, which acts as a clamp. Metal strips
(such as old feeler blades) can be used,
provided all burrs which may damage the
sealing strips are first removed (see
illustrations).
73 Where applicable, oil both sides of the
metal strips, and hold them on the sealing
strips. Fit the No 1 main bearing cap, insert
the bolts loosely, then carefully pull out the
metal strips in a horizontal direction, using a
pair of pliers (see illustrations).
74 Tighten all the main bearing cap
bolts/nuts evenly to the specified torque.
Using a sharp knife, trim off the ends of the
No 1 bearing cap sealing strips, so that they
protrude above the cylinder block/crankcase
mating surface by approximately 1 mm (see
illustrations).
75 On 1580 cc, 1761 cc and 1905 cc
engines, refit the centre main bearing side
retaining bolts and sealing washers (one at the
front of the block, and one at the rear) and
tighten them both to the specified torque.
76 Fit a new crankshaft rear oil seal as
described in Part B of this Chapter.
77 Refit the piston/connecting rod
assemblies to the crankshaft as described in
Section 19.

78 Refit the Woodruff key, then slide on the
oil pump drive sprocket and spacer (where
fitted), and locate the drive chain on the
sprocket.
79 Ensure that the mating surfaces of the
front oil seal carrier and cylinder block are
clean and dry. Note the correct fitted depth of
the oil seal then, using a large flat-bladed
screwdriver, lever the old seal out of the
housing.
80 Apply a smear of suitable sealant to the oil
seal carrier mating surface. Ensure that the
locating dowels are in position, then slide the
carrier over the end of the crankshaft and into
position on the cylinder block. Tighten the
carrier retaining bolts to the specified torque.
81 Fit a new crankshaft front oil seal as
described in Part B of this Chapter.
82 Ensuring that the drive chain is correctly
located on the sprocket, refit the oil pump and
sump -refer to Part B or C of this Chapter.
83 Where removed, refit the rear timing cover
and cylinder head as described in Part B.

19 Piston/connecting rod

assembly - refitting and big-
end bearing clearance check

4

Selection of bearing shells

1 On most engines, there are two sizes of
big-end bearing shell produced by Peugeot; a
standard size for use with the standard
crankshaft, and an oversize for use once the
crankshaft journals have been reground.

2 Consult your Peugeot dealer for the latest
information on parts availability. To be safe,
always quote the diameter of the crankshaft
big-end crankpins when ordering bearing
shells.
3 Prior to refitting the piston/connecting rod
assemblies, the big-end bearing running
clearance should be checked as follows.

Big-end bearing 
running clearance check

4 Clean the backs of the bearing shells, and
the bearing locations in both the connecting
rod and bearing cap.
5 Press the bearing shells into their locations,
ensuring that the tab on each shell engages in
the notch in the connecting rod and cap. Take
care not to touch any shell’s bearing surface
with your fingers (see illustration). If the

Engine removal and overhaul  2C•21

18.73a  Fitting No 1 main bearing cap,

using metal strips to retain the side seals

18.74b  . . . then trim the sealing strips, so

that they protrude above the cylinder block

mating surface by approximately 1 mm

18.74a  With all bearing caps correctly

installed, tighten their retaining nuts and

bolts to the specified torque . . .

18.73b  Removing a metal strip from No 1

main bearing cap using a pair of pliers

18.72b  Using the Peugeot special tool to

fit No 1 main bearing cap

18.72a  Fitting a sealing strip to 

No 1 main bearing cap

2C

19.5  Fitting a bearing shell to a connecting

rod - ensure tab (arrowed) engages with

the recess in the connecting rod