Land Rover Defender 90 110 Workshop 1984 Rover Manual

							2.25 LITRE PETROL AND DIESEL CYLINDER HEAD 112 I . 
- Reface valve faces .; c. 
68. Valves  that are satisfactory  for further  service can 
be 
rcfaced. This  operation  should be carried out 
using  a valve  grinding  machine.  Only the 
minimum  of material  should  bc rcmoved from the 
valve  face 
to avoid thinning  of the  valve  edge. The 
valve  is refaced  correctly  when all pits  are 
removed  and the face concentric  with the stem. 
Valve  face angles: 
A. Petrol  engine 
Inlet valve  face - 30 - I/JO 
Exhaust  valve  face - 45 - 
-. B. Diesel engine 
Inlet valve  face -445- % 
Exhaust  valve face 45 - % 
h A A 
ssE9?LJE 
+ F 
ST690M 
I 
v ST691 M 
Lap-in valves 
69. To ensure  a  gas  tight  seal between  the  valve facc 
and valve  scat it is necessary  to lap-in the 
appropriate  valve 
to its seat. It is essential to keep 
the  valve  identified  with its seat once  the 
lapping- 
in operation  has been  completed. Rcmember that 
the  inlet  and  exhaust  valves 
in thc petrol engine 
have different  face angles. 
70. Unless  the  faces  to be  lapped  are in poor 
condition 
it should  only  be  necessary  to use fine 
valve  lapping  paste. Smear  a small  quantity  of 
paste 
on the  valve  face  and  lubricate the valve 
stem  with engine  oil. 
71. Insert the valve in the appropriate  guide and using 
a  suction  type  valve lapping  tool  employ 
a light 
reciprocating  action  while  occasionally lifting the 
valve  off  its seat  and turning 
it so that  the valve 
returns 
to a diffcrent position  on the seat. 
72. Continue  the  operation until a continuous  matt 
grey  band  round 
thc valve  face is obtained. To 
check  that the  lapping  operation  is successfull, 
wipe off the valve paste from  the  valve and  scat 
and  make 
a serics of pencil  lines across  the valve 
face.  Inset  the  valve into the guide  and  while 
pressing  the valve  onto the seat  revolve  the  valve 
a  quarter  turn a few  times.  If 
all the pencil lincs 
are cut through  no further  lapping  is required. 
73. Wash all traces  of grinding  paste  from the valves 
and  cylinder  head seats. 
con tin lied 
ST670M 
Assemble  valves to cylinder head 
74. Insert the inlet  valves  into the guides and fit new 
oii  seais 
with the piain exterior  and circuiar 
spring.  Ensure  that 
the seal  locates in the groove 
in 
the valve  guide. 
75. Insert  the exhaust  valves and fit the oil seals with 
the  ridged  exterior  and no spring. 
continued 
39  
						

							1121 2.25 LITRE PETROL AND DIESEL  CYLINDER HEAD 
76. Fit the double  valve spring  and retainer  assembly 
to  each  valve in turn  and using  valve  spring 
compressor, 
18G106A with  adaptor 18G106A/10 
secure  the assembly  with the split collcts. 
74 
ST6 75 
ST669M 79 Examine  the rocker  shaft for wear  and  discard if 
ST 
~76 
80 
OVERHAUL  ROCKER SHAFT ASSEMBLY 
Most of thc rocker  shaft  assembly  components are not 
interchangeable  between  the petrol  and  diesel engines 
although  the assembly  method is the  same. 
Dismantle and inspection 
77.  Remove  the  locating  screw  and washer  from the 
number  two rocker  bracket  and  withdraw  all the 
components  from the rocker  shaft.  Note  that 
on 
the petrol  engine the locating screw also retains  a 
splash  plate. 
78. Remove  the locknuts  and adjustment  screws from 
the rockers. 
40 
the  bearing surfacc is worn  more  than  0,025 mm 
(0.001 in). 
Inspect thc rockers  and  discard if the pads are 
worn.  It is not  permissible to grind  pads in an 
attempt to  reclaim the rockers. 
Renew  bushes 
if the clearance  between shaft and 
bush  is 
in excess  of 0,101 to 0,127 mm (0.004 to 
0.005  in). 
Press 
in replacements ensuring that thc pre-drilled 
oil  holes  coincide 
with the holcs in the rockcrs. 
Illustration  A. 
Cross section of petrol  engine 
rocker. 
Illustration 
B. Cross section of diesel  engine 
rocker. 
ST684M 
81. Using  a  reamer  finish the  bushes  to 13,4 mm + 
0,02 mm (0.530 in + 0.001 in) and  clear  swarf 
from  the oil holes. 
82. Examine  the ball-end of the adjusting  screws and 
discard  any  that  are worn.  Regrinding  is not 
permissible.  Check  the  threads for damage  and 
that 
the oil  relief  drilling  is clear.  
						

							2.25 LITRE PETROL AND DIESEL  CYLINDER  HEAD 1121 
,,: :.:;,,.+ Assemble rocker shaft assembly >::. ;:.?a? .. _.-. ,, ,. .... + .q, : _I 83. Check  that the oil-ways in the rocker  shaft  are 
clear  and 
fit number  two rocker  shaft  bracket to 
the shaft and  retain  with the locating  screw  and 
washer.  Note that 
the locating  screw on petrol 
engines also  secures the splash  plate. 
84. Using  new  spaccrs and  springs,  assemble  the 
rockers  and brackets  to the  shaft  as  illustrated, 
ensuring  that the rockers  move freely 
on the shaft. 
Note  that  the Diesel  engine  assembly  has double 
spacers each  side 
of the centre pedestal. 
Illustration 
C. Petrol  engine  assembly. 
Illustration 
D. Diesel  engine  assembly 
. 
85. Fit the tappet  adjustment  screws and lock nuts to 
86. Invert  the  rocker  assembly  and  locate it on the 
the 
rlxkers. 
rocker cover to 
prevent it falling apart. 
continued 
C 
D 
f 
814 ST688M 
41  
						

							1121 2.25 LITRE PETROL  AND DIESEL  CYLINDER  HEAD 
92. Adjust the tappet clearances for  petrol and diesel 
engines,  inlet and exhaust 
to 0,25 mm (0.010 in) 
Fit the  cylinder  head 
as 
follows: Using a  feeler  gauge adjust  the 87. Cleaii the cylinder head  and cylinder  block mating 
clearance by slackening  the locknut  and  turning 
faces 
and 
fit a new  gasket,  dry, without  grease or 
the  tappet  adjusting  scrcw clockwise to reduce sealing compound.  The gasket will have either 
clearance and  anti
-clockwise  to  increase DIESEL or PETROL stamped in the position 
clearance. 
illustrated 
and the gasket must be fitted 
with these 
uppermost. 
88. Place  the cylinder  head in position  and  engage all Set No. 1 tappet with No. 8 valve fully open. 
the  cylinder  head bolts and washers  except  those  Set 
No. 3 tappet with No. 6 valve fully open. 
used  to secure the rocker  assembly. 
Use new bolts Set No. 5 tappet with No. 4 valve  fully open. 
and ensure  that the correct  bolts for the petrol and Set No. 2 tappet with No. 7 valve fully open. 
diesel  engine  are fitted.  They are not Set No. 8 tappet  with No. 1 valve fully open. 
interchangeable. Set No. 6 tappet with No. 3 valve fully open. 
Set 
No. 4 tappet with No. 5 valve fully open. 
Set 
No. 7 tappet with No. 2 valve  fully open. 
93. Recheck  the  clearances  with the locknuts 
tightened  and adjust 
as necessary. 
ST687M    ~ 
89. Insert  the 
push rods into position  ensuring  that 
the  ball
-ends fit correctly  into  the spherical  seats 
in the tappet  slides. 
90. Fit the  rocker  shaft  assembly  ensuring  that  the 
hole 
in the  front  and  rear  rocker  bracket  locates 
properly 
in the  corresponding  dowel in the 
cylinder  head.  Also, make 
sure that thc ball-end 
of  all  the rockers 
fit into the  spherical  seats of the 
push  rods.  Evenly  tighten  the  rocker shaft 
retaining bolts 
to the  correct  torque. 
91. Tighten  the cylindcr  head and rocker  shaft 
securing  nuts 
and bolts strictly in the  sequence 
illustrated 
to avoid  distortion  of the  cylinder  head. 
Tighten 
to the  torque  figures given in the data 
section. 
The arrow  points to the  front  of the 
engine  
						

							2.25 LITRE PETROL AND DIESEL CYLINDER HEAD 
_- 94. Using  a new  gasket fit the rocker  cover and  secure 
with the rubbers, cups and dome  nuts.  Tighten to 
the correct torque figure. Do not over-tighten. 
A. Petrol. B. Diesel 
- :,. 
ST671 M 
ST672M 
107.  Refit or reconnect  the items  disturbed for access 
to the cylinder  head. 
108. 
Refill the  cooling  system  when engine  is refitted 
to  vehicle. 
95. 
Fit the  inlet  and exhaust  manifolds  complete with 
carburetter (petrol  engine). 
Sec Engine overhaul. 
96. Fit the  air  intake  and  exhaust manifolds  (diesel 
enginc).  See Engine  overhaul. 
97. 
Fit the spark  plugs (petrol engine). 
98. Fit the injectors-see  Diesel  fuel system. 
99.  Fit 
thc engine  lifting cycs. 
100. Fit the water  temperature  sensor. 
Fit the thermostat  housing assembly 
101. IJsing a new joint  washcr  secure the thermostat 
housing 
to the  by-pass  housing. 
102. Fit the two hose adaptors. 
103.  Inscrt the 
thcrmostat into its housing. 
104. Place a ncw joint  washer  on the cy!inder head. 
105.  Using 
ii new joint  washer fit the thermostat  cover 
and  cowl  mounting  bracket. 
106. Using the. three bolts sccurc the  complete 
assembly  to the  cylindcr  head. Note that one bolt 
is  shorter  and is fitted in
-board. 
43  
						

							2.5 LITRE PETROL ENGINE 
2.5 LITRE PETROL ENGINE 
SUPPLEMENT TO THE 2.25 LITRE  PETROL 
ENGINE  OVERHAUL PROCEDURES 
This Supplement  should be used  in conjunction  with the 2.25 litre petrol  engine  overhaul  procedures. 
Details 
of the differences  between the 2.25 and 2.5 litre engines are listed  below. Some of the  new  features 
were,  however,  introduced  on later 
2.25 pctrol  engines. I 
0 Capacity  increased to 2495 cc by lengthening  the 0 
piston stroke  from 89 mm to 97 mm. 
0 
0 Crankshaft  and  main bearings  same  as the  2.5 litre 
Diesel  engine. 
T 
0 0 Oii squirt hole in connecting  rods deleted. 
0 New pistons with controlled  expansion skirts. 
0 Camshaft same as 2.5 litre Diesel  engine. 0 
0 Camshaft  sprocket similar  to 2.25  litre petrol  engine, 0 
but  with a single  keyway  positioned  to alter  the 
exhaust  value peak from  109” 
to 104”. 
Inserts fitted to exhaust  valve seats in cylinder  head. 
New timing chain tensioner  assembly 
Modified  oil pump 
with gear  having only ten teeth. 
Bush  deleted  from idler gear  and ball ommitted  from 
the  pressure  relief valve. 
The 
‘0’ ring  scal  between the flywheel housing  and 
cylinder  block deleted.  Sealing  now achieved  by 
a 
bead of sealant on  the flywheel  housing mating face 
with  the cylinder  block. 
Sump  joint washer  deleted  and a liquid  sealant, 
RTV 
Hylosill 102, now  used. 
The Lucas 45 D4 sliding  contact  distributor  now 
used. 
44  
						

							2.5 LITRE PETROL  ENGINE 112 
...-,.. _..._. ,+ . : : REMOVE  AND OVERHAUL  OIL PUMP Dismantle oil pump , :i:: ...,... :i i ,.. !. _, . -., , 
1. Remove the sump. 
2. Bend back the lock  washers  and remove  the two 
bolts  securing  the 
oil pump to the crankcase. 
Withdraw 
the oil pump  complete  with strainer  and 
oil  pump  drive shaft. 
3. Bend  back the lock  washer  and release  the  nut 
securing 
the strainer to the  oil pump  body  and 
remove  the strainer  and sealing ring. 
4. Remove  four bolts  and washers  and lift off the  oil 
pump  cover and 
lift out the driven  and  idler  gears. 
(a)  driven  gear 
(b) 
idlcr gear 
5. Remove  the oil pressure  relief valve  plug  and 
sealing  washer.  Withdraw the relief  valve  spring 
and  plunger. 
STlG35M 
Overhaul the oil pump 
6. Examine the  gears  for wear, scores  and pits. If the 
gears  appear  serviceable  check 
for end-float as 
follows: 
7. Clean  the  pump  body and assemble the gears. 
Place  a straight  edge across  the pump  body face, as 
illustrated,  and using  a  feeler gaugc,  measure the 
clearance  between the body  and gears  and  the 
backlash  between the 
gcars. The correct clearances 
are  given 
in Data. 
7 
ST1636M 
8. Gears  must be renewed in pairs. A worn, but 
serviceable  gear, must 
not be matched with a new 
one. 
9. If necessary  renew idler  gear spindle  by drilling-out 
the  peened  over  end of the  spindle 
so that  the 
spindle  can be withdrawn  from the pump  body. 
To 
ensure squareness  when fitting  the new  spindle, 
assembie 
it inio the pump  body with the two gears. 
Fit  the  cover  and secure 
with the four  bolts. 
Support  the pump  body and peen  over  the  end of 
the  new  spindle.  Remove  the  cover and gears  and 
check  security  of the spindle. 
45  
						

							)121 2.5 LITRE PETROL ENGINE 
Assemble the oil pump 
10. Fit the  idler  gear to the  spindle. 
11. Fit  the  driven  gear with plain  part of the bore 
uppermost. 
See illustration  after instruction 9. 
ST1637M 
12. Smear thc joint  face of the body  with jointing 
compound  and fit the  cover  over the dowels  and 
secure 
witli the lour bolts and  spring  washers. 
13.  Hold  relief valve  bore vertically  and insert 
the 
plunger  with the solid  end first. Fit the spring, 
sealing  washer  and plug. 
14. Fit the oil strainer  sealing ring to the pump  body 
followcd by the  lock  washer  and strainer.  Tighten 
the  strainer  retaining  nut 
so that when  fitted  the 
strainer  is positioned  parallel to the  sump  baffle 
plate.  Secure  the nut  with  the lock  washer  tab. 
REMOVE  AND OVERHAUL  THE TIMING  CHAIN 
SPROCKETS  AND TENSIONER 
1. Remove  the bolts  and withdraw  the timing  cover. 
2.  Before  removing  the timing  chain tensioner  check 
dimension 
A, which  with a new  chain  and 
sprockets  should 
be 14,22 mm (0.5 in) 
approximately.  This will give  an indication 
of chain 
wear.  The dimension  for a fully  worn  chain  is 27 
mm 
(1.06 in). 
3. Remove  the three  bolts and whilst  holding  the pad 
inwards,  to prevent 
it falling  apart, remove thc 
tensioner  asscmbly. 
4. Remove timing chain damper. 
5. Remove  the camshaft  sprocket retaining  bolt and 
washer. 
ST1665M 
6. Withdraw  the camshaft  sprocket together with the 
timing  chain and crankshaft  sprocket. If necessary 
use  special 
tool 507231. 
46  
						

							2.5 LITRE PETROL ENGINE 
12 L 
7. Examine the sprockets  and discard if the teeth  are 
8. Dismantle  the tensioner  assembly and discard if 
9. Examine  the tensioner  body and check  that the oi! 
10. Examine the slipper  and check  that the oil outlet 
11. Check  that the oil inlet  and exit  oil hole in the 
worn. 
, 
any of the 
parts  are worn. 
inlet  hole is clcar. 
hole  is clear. 
tensioner  mounting  plate is clear. 
12. Assemble  the tensioner body to the  mounting  plate 
with the two  socket  headed  screws, spring washers 
and  nuts. 
....- ... . . ,. ,:. . 13. Insert the spring  into the slipper  bore. 
14. Fit the  ratchet  over the spring and against  spring 
pressure,  insert the ratchet  into the slipper  bore 
so 
that the groove in the  ratchet  locates over the small 
dowel  inside 
the slipper  bore. Push and turn  the 
ratchet  clockwise  until 
it locks in the bore. 
15. Insert the slipper  assembly  into the tensioner body 
ensuring  that the small  flat on the  slipper  shaft 
faces the mounting  plate. 
ST7657M 
16. To prevent the tensioner  releasing,  insert a spaccr 
approximately 2.3 mm thick between  the tensioner 
body and  back  of the  slipper  prior to fitting to 
engine. 
ST 1 662M 
47  
						

							112) 2.5 LITRE PETROL ENGINE 
VALVE TIMING 6. Fit and  adjust  the timing  chain damper so that 
there  is 
a maximum  clearance of 0,25 mm 
(0.010 in) between  the timing  chain and damper. 
Tighten 
thc retaining  bolts and secure  with new 
lock  tabs. 
1. Check  that numbers  one and four  pistons  are still  at 
T.D.C.  and without  disturbing  the crankshaft, 
remove 
the pulley and timing  cover. 
2. Fit the camshaft  sprocket temporally  and rotate  the 
camshaft  in a clockwise  direction until the line  on 
the  tooth,  also marked  with a letter 
‘P’ is in line 
with  the top  stud  hole  on the  cylinder  block as 
illustrated. II 
 
3. Remove  the camshaft  sprocket. 
4. Encircle the camshaft  and crankshaft  sprockets 
with  the timing  chain and keeping 
it taut  on the 
drive  side and with  the large  shoulder 
of the 
crankshaft  sprocket towards 
the cylindcr block, fit 
the sprockets  and chain  assembly to the engine. 
5. Secure  the camshaft  sprocket to the camshaft  with 
a  new  special  micro encapsulated  treated bolt and 
tighten  to the  correct  torque figure. 
FIT TIMING CHAIN TENSIONER 
1. Fit the timing chain tensioner  and mounting  platc 
assembly 
to the cylinder  block locating it ovcr the 
two  dowels. 
2. Secure  the assembly  with the three bolts and evenly 
tighten. 
3. Remove  the spacer  and to release  the ratchet, to 
tension  the chain, prcss the pad  at point ‘A’.