Land Rover Defender 90 110 Workshop Book 2 Rover

							2.25 LITRE PETROL AND DIESEL ENGINE 112 
REMOVE  THE CONNECTING-RODS  AND PISTONS  REMOVE,  INSPECT AND OVERHAUL 
CRANKSHAFT 
- During the following  instructions  it is  important  that all 
components  are kept 
in related  sets and the pistons  arc 
identified  with their  respective  bores. 
1. Turn the crankshaft to bring  the connecting-rod 
caps 
to an  accessible  position and remove  each cap 
and  lower  shell in turn.  Note that the connecting
- 
rod caps  are numbered  one to four. 
1. Remove the eight  bolts securing  the flywheel 
housing  to the  cylinder  block and remove 
the 
housing  and rear  main  bearing  oil seal,  and ‘0’ 
ring. 
. 
ST718M 2. Push each  piston  asscmbly  up the  bore  and 
withdraw  from the cylindcr  block. Assemble  the 
caps  and shell.?  to the  connecting
-rods  and place to 
one  side  for inspection  with the cylinder  block at a 
later  stage. 2. Remove the main  bearing  caps and shells  and lift 
out the crankshaft.  Collect the bearing  shells from 
the  bearing  saddles and the thrust  washers  from 
thc 
centre saddle. 
...,.. .. . .. . continued 
7  
						

							1121 2.25 LITRE PETROL  AND DIESEL  ENGINE 
Inspect crankshaft 
3. Degrease the crankshaft  and clear  out the oil ways, 
which  can become  clogged  after long service. 
4.  Examine  visually, the crankpins  and  main bearing 
journals,  for obvious  wear, scores,  grooves  and 
overheating. 
A decision  at this  stage  should  be 
made  as  to whether 
the condition  of the  shaft  is 
worth  continuing  with more  detailed  examination. 
5.  With  a  micrometer,  measure and note  the ovality 
and  taper 
of each  main  bearing  journal and 
crankpin  as follows: 
6. 
Ovality - Take  two readings  at  right-angles to 
each other at  various intervals. 
The  maximum  ovality  must 
not exceed 0,040 mm 
(0.0015  in). 
7. Taper - Take two readings  parallel to each  other 
at  both  ends of the  main  bearing  journal  and 
crankpin. 
The maximum  permissable  taper must 
not exceed 0,025 mm (0.001 in). 
8. To check  for  straightness,  support  the  front and 
rear  main  bearing  journals 
in ‘V’ blocks and 
position  a dial  indicator 
to check the run-out at the 
centre  main bearing  journal.  Run
-out must not 
exceed  0,076 mm (0.003 in) taking into account 
any  ovality 
in the centre journal. 
The  overall  allowable  wear limit should  not exceed 
0,11,4 mm (0.0045 in)  for main  bearing  journals 
and  0,088 
mm (0.0035  in) for crankpins. 
A crankshaft  worn  beyond the limits  of maximum 
taper, ovality  and overall  wear can be  ground 
undersize for  which bearing  shells arc available  see 
data,  book 
1. 
When  grinding  the  crankshaft  main bearing  and 
crankpin  journals,  rotation 
of the  grinding  wheel 
and  crankshaft  must be 
in the  same  direction, 
anti
-clockwise,  viewed  from the flywheel  end of the 
crankshaft.  Final finishing  of the  journals should  be 
achieved  by 
using a  static tapping stone with the 
crankshaft  rotating 
in a clockwise direction  viewed 
from 
the flywheel  end of the crankshaft.  It is 
important 
to ensure  that, when  grinding,  the stone 
travels  beyond  the edge 
of the journal ‘A’ to avoid 
formation 
of a  step ‘R’ as  illustrated. Also care 
must  be taken 
not to machine or damage  the fillet 
radii.C. 
1 
EXAMINE  AND  OVERHAUL THE CYLINDER 
BLOCK 
1. Degrease  the cylinder  block  and carry out a 
thorough  visual examination  checking  for  cracks 
and  damage. 
To check  the  main  bearing  caps and 
saddles  for  distortion.  Fit the  main  bearing  cap 
without  bearing  shells and tighten  to the  correct 
torque.  Slacken  and remove the  bolt 
on one side  of 
each  bearing cap and  check with a feeler gauge that 
no clearance  exists at  the  joint face  between  the 
cap  and  saddle. 
Inspect cylinder bores 
2. Mcasure the cylinder  bores for ovality, taper and 
general  wear, using any  suitable  equipment. 
However,  an inside  micrometer  is best  for checking 
ovality  and a cylinder  gauge for taper. 
3. Check  the ovality of each  bore  by taking 
measurement  at the top of the  cylinder just  below 
the  ridge  at two  points  diametrically  opposite. The 
difference  between 
the two figures  is the ovality of 
the  top  of the  bore.  Similar  measurements  should 
be  made  approximately  50 
mm (2.0 in) up from the 
bottom 
of the  bore so that  the overall  ovality may 
be  determined. 
4. 
The taper  of each  cylinder  is determined  by taking 
measurements  at 
the top and bottom of each bore 
at  right  angles  to 
thc gudgeon  pin line.  The 
difference  between  the two  measurements  is 
the 
taper. 
5. To establish  maximum  overall bore  wear,  take 
measurements  at as many points 
possible down the 
bores  at right  angles 
to the  gudgeon  pin line.  The 
largest  recorded  figure  is the  maximum 
wcar and 
should  be compared  with 
the original diameter  of 
the  cylinder  bore. 
Maximum permissible ovality 
0,127 mm (0.005 in). 
Maximum permissible  taper 0,254 mm (0.010  in). 
ST1808M 
8 
Maximum  permissible  overall  wear  0,177 mm 
(0.007 in). 
con t I n ued 
pi 
F  
						

							2.25 LITRE PETROL AND DIESEL ENGINE 
t ., .I....:? .._. _._.. If the  above  figures  are exceeded the cylinders 
must  be rebored  or sleeved  depending  upon 
the 
general condition of the bores  and amount  of wear. 
Alternatively,  if the  overall  wear, taper and ovality 
are  well  within  the acceptable  limits and the 
original  pistons are serviceable  new piston  rings 
may  be fitted.  It 
is important  however, that the 
bores  are deglazed,  with 
a hone, to give a cross- 
hatched finish to provide  a seating  for the  new 
rings.  It is vital  to thoroughly  wash the bores 
afterwards  to remove  all traces 
of abrasive 
material. 
.. .. ;, .>I._ :_. .. ... . .. 
12 
Inspect  camshaft  bearings 
9. Measure the internal  diameter  of each  camshaft 
bearing  at several  points using an internal 
micrometer.  A comparison 
of the  bearing 
diameters  with those  of the  respective  camshaft 
bearings  should be renewed 
if the clearance 
exceeds  0,0508 
mm (0.002 in). Or, in any event, if 
they  are scored or pitted. 
T  ~ journals will give 
the amount  of clearance.  The 
Fit cylinder  sleeves 
Cylinder  bores that cannot be rebored  can be restored 
by  fitting  sleeves 
to enable  standard  size pistons to be 
fitted.  Sleeving  one cylinder  only will distort  the 
adjacent  bore 
so sleeving must be carried  out in pairs, 
i.e.  cylinders 
1 and  2 or 3 and  4. 
6.  Machine  the cylinder  bores to accept  the sleeves 
to 
94,425 + 0,012 mm (3.7175 + 0.0005  in). This  will 
give  the sleeve 
a 0,076  to 0,114 mm (0.003  to 
0.0045  in) interference  fit. 
7. Press the sleeves  squarely  into the bore  using  a 
pressure 
of two to  three  tons. Exccssive pressure 
could  damage  the sleeve  and cylinder  block. The 
sleeves  must 
not be proud  of the  cylinder  block top 
face 
or more  than 2,5 mm (0.10 in) below  the 
surface. 
8. 
Borc and  hone  the sleeves to accommodate  the 
pistons  with the required  clearances,  see piston  and 
connecting
-rod  examination. 
RENEW CAMSHAFT BEARINGS 
The  following  special tools for this  operation  are 
no 
longer available  from the suppliers.  However, the 
operation  is nevertheless  described for workshops  that 
have  these  tools in stock.  If tools  are not obtainable  the 
work 
should be  entrusted  to line-boring  specialists. 
605975  Bearing  drift and adaptor  assembly  comprising: 
274388  Bearing  drift and 
531760  Adaptor. 
274389  Reamer  for bearings  which includes: 
274394  Guide plug. 
1. Remove the rear bucket  type plug  and using  special 
tool  274388  drift 
out the front  and rear  bearings 
and withdraw  them through  the side  cover 
apertures. 
2. With  the same  tool, drift the two  centre  bearings 
into  the distributor  drive chamber  and collapse 
them  to assist  withdrawal. 
continued 
9  
						

							2.25 LITRE PETROL  AND DIESEL  ENGINE 
NOTE: The two centre  and rear  bearings  are of the 
same  width,  whereas  the front  bearing  is wider  and 
has  an additional  oil feed  hole. 
Also ensure  that 
before  fitting the bearings  the oil passages  leading to 
the  bearings 
are free of sludge  and dirt. 
3. Position  the cylinder  block vertically,  rear face 
down. 
4.  Place  a new  bearing  into the front  camshaft 
chamber  and position  it 
so that it is above  the 
second  bearing  housing,  counting  from the front 
of 
the block. 
5. The  chamfer  on the  bearing  edge must  be  towards 
the  housing  bore. 
6. Align the oil hole  in the  bearing  with the innermost 
oil  feed  drilling  in the  housing  bore. Accuracy  is 
essential  otherwise  misalignment  of the 
oil holes 
may  result  and once  the bearing  is 
in place it cannot 
be  rotated  to correct  any error. 
7. Add  pencil  marks  to the  bearing  outer diameter 
and  the cylinder  block adjacent  to the  housing 
to 
assist  in checking  alignment. 
8. Having visually  aligned the bearing,  place inside  it 
the  special  adaptor 
531760. 
- 
3 
 
9. Maintain  the bearing  in a level  position.  Pass the 
drift  through  the front  bearing  housing  into the 
camshaft  chamber 
so that it rests  on top  of the 
adaptor.  Commence  drifting 
the bearing into the 
block.  Ensure  that the bearing  is not  drifted 
in too 
far,  and  that  the 
oil feedholes are correctly 
aligned. 
10. Repeat  the above  instructions  for the  front 
bearing.  Note that the front  bearing 
is wider  and 
has  a small  hole in addition 
to the  large oil feed 
hole.  This small  hole aligns  with a vertical  drilling 
in the block,  which in turn  feeds  a horizontal 
drilling  for 
the tappet mechanism.  Drift this 
bearing  in 
so that the outer  edge is just  below  the 
machined  surface of the  front  face. This is to 
ensure  that when  the camshaft  thrust plate is fitted 
it will  not stand  proud  on the  bearing  edge. 
lillllllilll - 111 \\\, 
11. Turn the cylindcr  block over so that the rear  face  is 
uppermost  and repeat  the foregoing  procedures 
for 
the two  remaining  camshaft bearings. 
The  bearings  must now be reamed  to size  as 
follows: No lubricant  is necessary  for this  operation 
since 
the best  results  are obtained  when the 
bearings  are cut dry. 
12. Locate  the guide  plug 274394,  into the front 
camshaft  bearing and retain  using the thrust  plate 
screws,  but do not  tighten  the screws  at this  stage. 
13. Insert  the reamer  274389 from the rear  of the 
cylinder  block, locating  it through  the guide  plug at 
the front. 
14.  Locate  the guide  collar  immediately 
in front of the 
rcamer cutter into the  rearmost  bearing, then 
secure  the screws  retaining  the guide  plug at the 
front. 
15. Position  the cylinder  block vertically,  rear face 
uppermost  and ream  the rear  and two centre 
bearings.  As each  bearing  is cut the  reamer  should 
be  held  steady  by the  operator  whilst an assistant, 
using  a high  pressure  airline, blows away the white 
metal 
cuttings, before  allowing  the reamer  to enter 
the  next  bearing. 
16. Remove  the guide  plug 274394  and ream  the front 
bearing. 
17. Remove  the reamer  handle and bolt  and withdraw 
the  reamer,  turning 
it in the  same  direction  as tor 
cutting. 
18. Remove  the plugs  from the ends  of oil  gallery 
passage  and clean 
the gallery  and oil feed  passages 
to  camshaft  and crankshaft  bearings, using 
dz, 
compressed  air. Refit  the plugs  and lock in k-v 
position. 
?$: .? .+ 
continued 
10  
						

							2.25 LITRE PETROL AND DIESEL ENGINE 112 
19. The hexagon-headed  plugs at the  rear of the block 
should  have new washers  fitted, and their  threads 
coated  with a suitable  jointing compound. 
20. Thoroughly  clean the cylinder  block preferably 
using an airline to remove all traces of metal 
cut t ings . 
Check  crankcase  main bearings 
21. Discard scorcd, pitted,  cracked  and worn bearing 
shells. 
22. To determine  the maximum  wear, assemble  the 
main  bearing  shells and caps  to the  crankcase  and 
tighten  the bolts  to 
the correct  torque figure. 
23. Using an inside  micrometer,  measure each bearing 
at  several  points and note  the greatest  figure. The 
maximum  wear is the  difference  between this 
figure  and the smallest 
diamcter of the 
corresponding  crankshaft journal. The main 
bearing  running  clearance  is in  the  data  section. 
24. The bearing  clearances  may also be determined  by 
using  ‘Plastigauge’.  Since this method  requires  the 
crankshaft  to be  fitted  to 
the crankcase,  the 
procedure  is described  under engine  assembly. 
PISTON  AND CONNECTING-ROD  INSPECTION 
The following  checks relating to pistons  and rings  must 
also  be carried  out prior  to fitting 
new pistons  to 
rebored  and sleeved  cylinder  blocks. 
Until 
it is  decided if new  components  are required all 
parts  must be kept  in their  related  sets and the position 
of  each  piston  to its  connecting
-rod should  be noted. 
1. Remove  the piston  rings and gudgeon  pin from 
each  piston  and 
dctach the connecting-rod. 
2. Original  pistons - Decarbonise  and dcgrease all 
the pistons  and rings  and discard any which  are 
unserviceable.  Pistons which appear  serviceable 
should  be subjected  to 
a more detailed 
examination  described under ‘New Pistons’. 
coi?;poiiefi:s aiid cairj ou: a vimal examinatim cf 
continued ST708M 
11  
						

							lcl 2.25 LITRE PETROL  AND DIESEL  ENGINE 
3. New Pistons - Original  pistons fitted to new 
engines  at the  factory  are specially  graded to 
facilitate  assembly.  The grade  letter 
on the piston 
crown  should  be ignored 
when ordering  new 
pistons.  Genuine  Land Rover  service  standard  size 
pistons  are supplied  0,025 
mm (0.001 in) oversize 
to  allow  for production  tolerances 
on new engines. 
When  fitting new pistons  to a standard  size cylinder 
block  the bores  must be honed  to accommodate 
the 
pistons with the  correct  clearances.  In  addition 
Land  Rover  pistons  are available 
0,50 and 1,Ol mm 
(0.020  and 0.040  in) oversize  for fitting to rebored 
cylinder  blocks. 
Clearance  limits for new  standard  size pistons 
in a 
standard  cylinder bore measured  at right  angles  to 
the  gudgeon  pin are 
in the  “General  specification 
data”  section. 
When  taking  the following  measurements 
the 
cylinder block and pistons  must be at the  same 
temperature  to ensure  accuracy. 
NOTE: The illustration  shows a petrol engine  piston 
but  the method 
is the  same for the Diesel  engine. 
4. Using a suitable  micrometer measurc the pistons  at 
thc bottom  of the  skirt  at right  angles  to the 
gudgeon  pin. 
5. With an inside  micrometer  or cylinder  gauge 
measure  the diameter 
of the  bore  at approximatcly 
half
-way  down  and note the reading. 
6. The clearance  is determined  by subtracting  the 
piston  diameter  from the bore  diameter. 
7. If gauge  equipment  is not  available  the clearance 
can  be assessed  by placing  a 
long, suitably  sized, 
feeler  gauge  down 
the thrust  side of the bore  and 
inserting  the appropriate  piston, ‘upside  down’, 
in 
the bore  and position  it with  the gudgeon  pin 
parallel  to the  crankshaft  axis. Push 
the piston 
down  the bore  and stop  at the  tightest  point and 
whilst  holding  the piston  still, slowly  withdraw  the 
feeler  gauge.  If a steady  resistance  of 
approximatcly 
2,5 kg (6 Ibs)  is felt,  the clearance  is 
satisfactory, 
Inspect  piston rings 
Normally  when an engine  is being  overhauled  the 
piston  rings are discarded  unless the pistons  have been 
removed  for a different  purpose and the engine  has 
only  completed  a small  mileage.  Before refitting  the 
piston  the rings  should  be examined  for wear  and 
damage. 
In addition  the rings  must be checked for side 
clearance  in the  pistons  and gap  in the  bores. 
The latter 
two checks  must be made  when fitting  new rings  to new 
8. Check gap When  checking thc ring gap in worn 
bores,  but are nevertheless  within the acceptable 
taper  and ovality  limits, 
the ring must  be inserted 
squarely  into the bottom 
of the  bore at the lowest 
point  of the  piston  travel. 
To ensure  squareness  of 
the  ring  push  the ring  down 
the bore  to the  correct 
position  with a piston.  With newly  machined  bores, 
the  ring  may  be inserted  squarely  into any position 
in  the  bore. 
9. Using an appropriate  feeler gauge  check the gaps 
of  all  the  rings, 
in turn,  including  the oil control 
4“‘. and  used  pistons. .e-, 
ring assembly. 
The  correct  gaps are listed  in the  Data  Section. 
If 
any gap IS less than  that specified, remove  the ring, 
and 
file the  ends  square,  whilst holding  the ring in a 
filing  jig or vice.  Should  any gap be excessively 
wide  and not likely  to close
-up  to within the 
specified  limits when hot, an oversize  ring should 
be  fitted. 
NOTE: Eariy 2.25 Diesel  pistons  have a piston ring 
groove  below the gudgeon  pin. This  has been  deleted  on 
later  engines. 
&--.. y;;; 
continued 
12  
						

							2.25 LITRE PETROL  AND DIESEL  ENGINE 
- Check piston ring side clearance 
Petrol  engine  pistons  have two compression  rings and 
one  oil control  ring assembly.  The diesel  engine  has 
three  compression  rings and one 
oil control  ring 
assembly. 
The method of checking  clearances  are the 
same for both  engines  but the clearances  are different. 
It is important  that clearances  are correct.  Rings that 
are 
too tight  will bind  when  hot, imparing  the radial 
pressure  causing possible 
loss of compression. 
Excessive  clearance will allow  the rings  to rock  in the 
grooves  and the resulting  pumping  action could cause 
excessive  oil consumption  and eventually  broken rings. 
12 
10. 
11 
12. 
13. 
Diesel engine  pistons - Fit the oil control  ring to 
the  bottom  groove (not groove 
in skirt). Fit the two 
unpolished 
rings with  the word  ‘TOP’  uppermost  to 
the  middle  two grooves.  Insert to polished  chrome 
ring  with  the internal  chamfer  to the  top  groove 
with  the word 
‘TOP’ uppermost. 
A  ring  groove  is provided  at the  bottom 
of the 
diesel  engine  piston skirt for the  fitment 
of an oil 
control  ring in cases 
of excessive  oil consumption 
on high  mileage  engines (early engines  only). 
Petrol engine  pistons - Fit the oil control  ring to 
the  bottom  groove. 
Fit the unpolished  compression 
ring  with  the word  ‘TOP’  uppermost 
to the second 
groove.  Insert the 
polishcd chrome  ring with  an 
internal  chamfer  and the word  ‘TOP’  uppermost  to 
the  top  groove. 
After  fitting  each ring, 
roll it around thc piston 
groove 
to ensure  that it is free  and does  not bind. 
Using  an appropriate  feeler gauge  check the 
clearance  between the rings  and piston  grooves. 
Clearances  in excess  of 0,106  to 0,152 
mm (0.004 to 
0.006  in) are  unacceptable  and the ring  and or the 
pistons 
shouid be  renewed. 
Side  clearance  data - petrol engine 
Compression  rings - 0,046 to 0,097 mm (0.0018 to 
0.0038  in). 
Oil control  ring - 0,038 to 0,089 mm (0.0015 to 
0.0035  in). 
Side clearance -died engine 
Compression  rings - 0,06 to 0,11 mm (0.0025 to 
0.0045  in). 
Oil  control  ring 
- 0,038 to 0,064 mm (0.0015 to 
0.0025  in). 
13 
Inspect  gudgeon  pins 
14. 
15. Check  the gudgeon  pin for wear,  cracks,  scores and 
overheating. 
The gudgeon  fit in the  piston  must be a tight  push 
fit at a temperature  of 68°F (20°C). Check the 
gudgeon  pin for ovality  and taper  using  a 
micrometer. 
Connecting-rod  inspection 
16 
17 
Check  the connecting-rods  and caps  for distortion 
as  follows; 
fit the  correct  cap, less the bearing 
shells, 
to each  connecting  rod as denoted  by the 
number  stamped  near the joint  faces.  This number 
also 
indicatcs the  crankshaft  journal to which it 
must  be fitted. 
Tighten  the nuts  to the  correct  torque and release 
the  nut 
on one  side  only.  Check,  with a feeler 
gauge,  that 
no clearance  exists between  the joint 
faces. 
if there is a gap the connecting-rod  is 
distorted  and should  be renewed. 
NOTE: Whilst  the illustration  shows a Diesel  piston 
the  method  for the  petrol 
is the same. continued 
13  
						

							2.25 LITRE PETROL AND DIESEL  ENGINE 
18. . 
19. 
20. 
21. 
ST716M 
Use an accurate connecting-rod  alignment  gauge to 
theck the rods  for  bend  and  twist. The maximum 
allowable  for  both  conditions  must 
not exceed 
0,127 
mm (0.005  ins). 
Examine  and check 
the small-end bush  for wear.  If 
necessary  renew the bush.  The correct clearance 
of 
the gudgeon  pin in the small-end  bush  is given in 
“General  specification  data”. 
When  renewing  a bush  ensure  that the oil hole 
in 
the  bush  lines  up with  the hole in the connecting- 
rod.  Finish  the bush  to the correct  size  and 
clearance.  Connecting
-rod  bearings  that are  worn,  pitted, 
scored  and show  signs 
of overheating  must  be 
discarded.  If more  than  one 
of the bearings  show 
these  signs they  must all be 
replaccd. When  fitting 
new 
or used  bearings  to reground (petrol  engines 
only)  or serviceable  crankpins the clearances  must 
be checked. 
As an  alternative,  the  bearing  clearances can be 
determined  by using  ‘Plastigauge’  which consists 
of 
a thin  piece of plastic  material  a  few hundreds of a 
millimeter or thousands of an  inch in diameter. 
When  the  material is flattened  by being  squeezed 
between  the bearing  and crankpin  the  width of the 
plastic  is measured  by a scale  gauge which  indicates 
the  clearance. 
23.  Wipe  any oil from  the crankpins  and place  a piece 
of  ‘Plastigauge’ across  the centre  of the  bearing 
in 
the  connecting-rod  cap.  Assemble  the  rod  to the 
appropriate crankpin and tighten to the correct 
torque. 
Do not rotate  the connecting-rod  or 
crankshaft during  this operation. 
24. Remove  the  connecting-rod cap  and  bearing  shell 
and  using  the scale  supplied  measure the flattened 
‘Plastigauge’  at its  widest  point. The graduation 
that  most  closely  corresponds to  the  width 
of the 
The  correct  clearance  with new 
or overhauled 
components 
is 0,019 to 0,063 mm (0.0007  to 
0.0025 in). 
25. Wipe off the  ‘Plastigauge’  with an  oily  rag. DO not 
scrape off otherwise it may  damage  the crankpins. 
:.;:;:$I c 
‘Plastigauge’ indicates  the bearing  clearance. ,$. -=>A. 
c:! 
23 
Connecting-rod bearing  nip and  clearance 
New bearing  halves  are supplied  with a protective 
coating and  must be degreased  before fitting. 
22. Fit the bearing  halves  to the  connecting-rod  and 
cap  and  secure  the assembly  with 
thc correct 
torque.  Slacken  the nut  on 
one side only and  check 
the  clearance  between the joint  faces  with a feeler 
gauge. 
The clearance  should  be  between 0,lO and 
0,20 mm (0.004 and 0.008 in).  The bearing  nip  can 
be  adjusted  by the  selective  assembly 
of the 
bearing  shells  which  are available  in  slightly 
varying  thicknesses. 
Do not file or machine  the 
caps 
or rods  to vary  the bearing  nip, Make a final 
check  to prove  the clearance  by inserting  a 0,063 
(0.0025 in)  shim  paper  between  the  crankpin  and 
one  half 
of the bearing  and tightening  to the  correct 
torque. 
The connecting-rod  should  resist rotation 
and  move  freely  with the shim  paper removed. 
end--oat 
26. Fit the connecting-rods  complete  with bearings to 
their  respective  crankpins.  Move the connecting- 
rod to one  side  and check  the clearance,  with a 
feeler,  on the  opposite  side. The correct  clearance 
is between 0,20 and 0,30 mm (0.007 and 0.012 in). 
continued 
14  
						

							I ..._ .. ./. ,, ... . . , . i . :,,,;, .. ... ~ ., . . . . . . ....,.. ..I. 
. . .- 
... 
. 
.I’. .. , .:.. ... .... .. 
2.25 LITRE  PETROL AND DIESEL  ENGINE E[ 
Assemble  pistons to connecting-rods 
27. Petrol engine  pistons  can be fitted  either  way 
round,  except  those that  are being  refitted  to their 
original  bores 
in which  case  they must  be fitted  to 
the  connecting
-rod  in the  same  position  in 
accordance  with the mark made  during removal. 
28. Inscrt a circlip in one side  of the  gudgeon  pin boss 
and  assemble  the piston  to 
the connecting-rod  with 
the gudgeon  pin. Secure  the assembly  with a circlip 
on  the  opposite side  of the  piston. 
29. Diesel  engine  pistons  must  only  be  fitted one way 
in  relation  to the  connecting
-rod.  The  piston  must 
be  assembled  with 
the point of the ‘V’, on the 
piston  crown,  on the  same  side 
as the lubrication 
hole  in the  connecting
-rod.  Assemble  the piston  to 
the  connecting
-rod in the same manner as for the 
petrol engine. 
Place 
the piston  and connecting-rod assemblics to 
one  side  ready 
for fitting to  the cylinder  block. It is 
good  practice  to renew 
thc connecting-rod  bolts 
ASSEMBLE ENGINE 
FIT  CRANKSHAFT 
Main  bearing  nip and  clearance 
New  main  bearing  halves are supplied  with a protective 
coating and  must be degreased 
beforc fitting. 
1. Fit the  bearing  halves in the crankcase saddlcs and 
caps  and secure  the  caps  to 
the crankcase and 
tighten 
to the correct  torque.  Slacken  the bolts on 
one  side of the caps only  and, with a feeler gauge, 
check 
the gap  between  the  joint faces. ‘The 
clearance or nip must  be within 0,lO to 0,15 mm 
(0.004 to 0.006 in).  The  bearing  nip can  be 
adjusted  by selective  assembly  of 
the bearing 
halves  available  in varying thicknesses. 
Do not file 
or machine thc caps or saddles to achicvc  the 
corrcct clearance. Note  that the rear  main  bearings 
are  wider than 
thc rcmaining four. 
2. To make  a final  check that the clearance  is correct, 
leave  the bearing  halves 
in the crankcase  saddles 
and  carefully  lower  the  crankshaft into position. 
Check  each bearing 
in turn by inserting a 0,063 mm 
(0.0025 in)  shim  paper  between  the  bearing cap 
and  crankshaft journal  and tighten  the bolts  to 
thc 
correct  torque. If the  clearance  is correct,  there 
should  be 
a slight increase in thc rcsistancc to 
rotation 
of the crankshaft. 
As  an alternative  ‘Plastigauge’  may 
bc used to 
check  the clearance 
in the same manner as with  the 
connecting
-rod  bearings.  This material  may also be 
used  to  determine 
the amount of wear in used 
bearings 
and jot”. 
continued 
ST722M 
15  
						

							2.25 LITRE PETROL AND DIESEL ENGINE ~~  ~~ 
3. Locate 
the crankshaft  in position  on the  upper 5. Place  the crankshaft in position  in the  crankcase eL? 
bearing  halves in the  crankcase  and wipe  any oil 
from  the journals  since ‘Plastigauge’  is soluble  in 
oil.  Place  a piece  of ‘Plastigauge’  across the lower 
half  of each  crankshaft  journal or lower  bearing 
cap  shell. 
Fit the cap  and  tighten to the correct 
torque.  Remove  the cap  and  bearing  and using  the 
scale  supplied  with the ‘Plastigauge’  measure the 
flattened  ‘Plastigauge’  at its  widest  point. The 
graduation  that most  closely  corresponds  with the 
width 
of the  ‘Plastigauge’  indicates the bearing 
clearance. 
The  correct  clearance  with new or overhauled 
components  is included  in “General  specification 
data”  section.  If new  bearings  are being  fitted use 
selective  assembly 
to obtain the correct  clearance. 
Wipe  off, not scrape  the ‘Plastigauge’  with an oily 
rag  from  the journals  or bearings.  and 
mount  a dial  test indicator  to read
-off  the end w3 
of the  crankshaft.  A feeler  gauge  may be used 
instead 
of an  indicator. 
6. Determine  the end-float  by moving the crankshaft 
away  from the indicator  and zero  the dial.  Move 
the  crankshaft  in the  opposite  direction  and notc 
the  indicator  reading. Alternatively  measure the 
clearance  with a feeler  gauge.  The end
-float  should 
be 
0,05 to 0,15 mm (0.002 to 0.006 in). 
7. If  adjustment  is required  substitute  with oversize 
thrust  washers.  Variation 
of thrust washer 
thickness  at each  side 
of crankshaft  journal must 
not  exceed 
0,08 mm (0.003 in) to ensure  that the 
crankshaft  remains centralised. 
Adjust crankshaft end-float 
4. Lift out the crankshaft  and insert  a standard  size 
thrust  washer  both sides 
of fhe centre  main bearing 
saddle  with the grooves  towards the crankshaft. 8. Lubricate the crankshaft main journals with clean 
engine oii and fit the  appropriate  bearing caps and 
lower  shells to the  crankcase  with the exception 
of 
number  five main  bearing.  Ensure that the caps 
locate  properly  over the dowels.  Using 
new bolts 
and washers  evenly tighten  to the  correct  torque 
figure. 
continued 
16