Land Rover 90 110 Workshop Rover Manual

							PETROL FUEL SYSTEM 1191 
f. -; I I- 7. Remove the short rebound spring. 
8. Clean all components  in paraffin. 
9. Immerse  pump body in petrol  and use air-line 
.. ., . * 
inside  pump  tube. 
2 
la 
/ --. 
s 
1 
I 
ST 1015M ‘d. 
NOTE:  The fuel filter  assembly,  instructions 2 and 
3, can be carried  out with  the pump  on the  vehicle. 
ASSEMBLE 
Pump  piston  assembly 
10. Fit the short rebound  spring. 
11. Fit the  return spring over the opposite  end of the 
12.  Slide  the piston  assembly  into the pump body. 
13. Fit the  following  items: 
piston. 
a)  plain  washer 
b) rubber  seal 
c)  one
-way valve 
14. Secure the assembly with the  spring clip. 
Fuel  filter  assembly 
15. Fit the filter  and seal. 
16. Fit the  magnet. 
17. Fit the  end  cover  with a new  gasket. 
18. Fit pump  to vehicle  and ensure  that  the earth 
connection lead  and its mounting point  is clean. 
CARBURETTER FOUR CYLINDER  ENGINE 
OVERHAUL 
DESCRIPTION 
The  twin  bored  32 - 34 DMTL Weber  carburetter  is a 
fixed choke  instrument  with a staggered  throttle 
opening.  The carburetter  is divided, operationally, 
into 
two  sections  namely the primary  and  secondary 
carburetters  with 32 
mm and 34 mm bores  respectively. 
The  delayed  throttle  opening  occurs 
in the secondary 
carburetter. 
The  primary  carburetter,  which incorporates  fuel and 
air  jets  for idling,  is used  for  starting,  and normal 
running,  up to approximately  two thirds  throttle 
opening.  Shortly before this stage  the  secondary 
carburetter  butterfly will begin 
to open  and  become 
increasingly  more involved  as the  throttle  is opened 
further.  To ensure  a  smooth  transition  during  the 
various  stages of throttle  opening  both  sections of the 
carburetter  contain  progression  fuel and 
air jets  and 
ports. 
To prevent  fuel vaporisation  and air locks in the  system 
fuel  is continuously  pumped back to the  fuel  tank  from 
the carburetter  float chamber.  The top of thc float 
chamber  is 
so designed that fuel is drawn  off  from thc 
main stream  via the  needle  valve as dictated  by the  fuel 
level in the chamber. 
DISMANTLE 
1. Remove  the carburetter. 
2.  Disconnect  the fast idle  cam assembly. 
3. Disconnect  the chokc link. 
4.  Disconnect 
the pull-down  lever and linkage. 
5. Remove  the top  cover from the carburetter  body. 
6. Withdraw the float  pivot  and detach the  float. 
7. Remove the needle  valve attached  to the  float tag. 
8. Remove znd discard  the gasket  from the top  cover. 
9. Withdraw the needle  valve housing. 
10. Remove  the fuel filter plug  and filter. 
11. Remove  the pull-down  capsule. 
12. Remove  the fuel  cut-off solenoid  and valve. 
13.  Withdraw  both  ‘primary’  and  ‘secondary’  idle 
jct 
holders noting their positions for ease of 
reassem bl y. 
14. Withdraw  both ‘primary’  and ‘secondary’  main jet 
assemblies,  comprising  main  jet, emulsion  tube 
and  air correction  jets. 
15. Lift out the pump jet. 
16. Remove  the  accelerator  pump cover,  diaphragm, 
gasket  and spring. 
17. Detach  the  economy pump assembly,  comprising 
cover,  spring and  diaphragm. 
18. Remove the idle  mixture control  screw. When  the 
adjustment  is tamper
-proofed,  the tamper- 
proofing  cap must  be removed  to expose the  screw. 
continued 
3  
						

							P 
ST 535 M 
19-49 5.47 
21.30  
						

							PETROL FUEL SYSTEM 119 I 
,,;. .. .:.: ~ )I. .. . .... .,,.._ ., . 19. Mark-up 
for  reassembly  purposes  and  remove the , , ,... .. . . ... choke  butterfly followed by the  choke spindle  and 
linkage. 
20.  Prior  to removal,  mark each throttle butterfly. 
21. Remove the throttle  linkage,  springs  and  washers, 
noting  their sequential  positions 
to aid rcassembly. 
22.  If required  remove  the  primary and sccondary 
throttle  butterflies  (after  marking
-up)  followed by 
the  respective  spindles. 
Inspection and cleaning 
23.  When  cleaning fuel passages, DO NOT use metal 
tools  which  could cause dimensional  changes 
in the 
drillings 
or jets.  Cleaning  should be effected  using 
clean  fuel, and, where  necessary,  a moisture  free 
air  blast. 
24.  If 
the joint faces  on the emulsion  block, top cover 
or carburetter  body show any  signs of distortion or 
the edges  are burred,  these faces may  be reclaimed 
by 
flatting, using  fine  grade abrasive  cloth and a 
surface  plate. Examine  the  faces for deep 
scores 
which  would  lead to leakage  taking  place when 
assembled. 
25.  New 
gaskcts and  seals  should  be used  throughout 
the  carburetter  rebuild.  A complete set of gaskets 
is  available 
for replacement  purposes. 
26.  Examine  the throttle  spindle  bushes  for wcar, 
if 
oval or badly  worn,  replace  the carburetter  body. 
27. 
Examinc the  idle  mixture  volume screw for wear or 
damage, replace  as required. 
. ,;.. I ., . .,: 
35. Fit  the  pump  jet with a new 0 ring  into the 
carburetter  body. 
36. Reassemble the primary jet to the jet holder and fit 
to the carburetter  body. 
37. Fit the secondary main and air  correction jets to 
the  secondary  emulsion  tube,  locate and secure 
assembly to  the carburetter  body. 
38. Assemble the secondary  jet to the jet holder  and fit 
assembly to  the carburetter  body. 
39. Reassemble the primary main and air correction 
jets 
to the emulsion  tube; and fit assembly  to the 
carburetter  body. 
40. Fit the  fuel  filter  and filter  plug to the  top  cover. 
41. Fit the needle  valve seating and  washer. 
42.  Place 
a new  gasket into  position. 
43. 
Fit the  needle  valve into the needle  valve seating. 
44.  Position  the float tag 
in the  needle  valve wire loop. 
Align  the float  carrier  with the pin  holes  and float 
carrier  flange 
lugs. Sccure the float  carrier with the 
hinge  pin. 
45. With the needle  valve on its seating  and the float 
carrier  tag resting  against  the 
necdle valve 
(ensuring  that neither  the valve  plunger 
nor the 
valve  ball are depressed) 
measurc the distance 
between  the casing  and 
thc front cdge of the  float. 
46. The dimension  required is 7 mm (0.27 in). Any 
adjustment  must  be made by bending 
thc float 
carrier  tag. Adjustments  must 
NOT be  made by 
bending 
the float  carrier arms. 
continued 
Reassembly .. . .. ,, .. ,. . . 28. If previously dismantlcd, insert  the  primary  and 
sccondary  throttle spindles  into their  respective 
positions. 
29. Locate  the primary  and  secondary  throttle 
butterflies  on to their  respective  spindles  and 
loosely  retain 
with the special screws.  Operate each 
buttcrfly to centralise it on each  spindle  and secure 
the  screws  and lock  them  by peening. 
30.  Refit 
the throttle  spindle assembly  to thc 
carburetter  ensuring the pin on the  free  lever 
locates 
in the  slot on the primary  shaft plate, 
ensuring  that  the  first spring  is located  on  the 
spacer, whilst the second  spring is engaged  on the 
free  lever. 
31. Fit the  accelerator pump assembly comprising 
spring,  gasket, diaphragm,  spring and pump  cover. 
32. Refit the economy  pump assembly  comprising 
diaphragm, spring and  pump cover. 
33. Replace  the fuel  cut-off valve and  solenoid. 
34. Fit the idle mixture  control screw and carefully  turn 
until fully home, then turn  the  screw 1 /r to 2 turns 
in the  reverse direction to serve  as an initial  setting. 
ST567 M 
. :F .. .. ... , 
7mm 
0.27in 
5  
						

							1191 PETROL FUEL SYSTEM 
47. Fit and secure the top cover  assembly  evenly, to 
48. Fit the  choke  spindle  into its housing. 
49. Locate  the choke  buttcrfly on the spindle  and 
loosely  retain with the two  special  screws.  Operate 
the  butterfly 
to centralise it on the spindle,  then 
secure  the screws  and lock  them  by preening. 
50. Refit the pull-down  capsule,  cable retaining 
bracket,  spacer and fixings. 
51. Fit the pull-down  lever engaging  the pivot  with the 
pull
-down  capsule  arm. Secure  lever assembly  with 
washer  and circlip. 
52. Fit the  float  idle cam  ensuring  the spring  is engaged 
correctly 
to the  cam. 
53. Refit  the choke  link to the choke spindle,  securing 
with  a new  split  pin. Engage  the opposite  end of 
the  choke 
link to the  idle  cam. 
the 
carburetter  body. 
7. Push the mixture  control fully in and confirm  that 
flap 
‘B’ is  open,  that is in  the  vertical  position. 
FOUR CYLINDER  ENGINE CARBURETTER 
TUNE AND ADJUST 
1. Before  attempting  any carburetter  adjustments 
ensure  that cylinder  compressions,  valve 
clearances,  spark plug gaps  and ignition  timing are 
satisfactory. 
Check  also that there  is 
no air leakage  into the inlet 
system  through  the 
inlet manifold  and carburetter 
n 
gaskets  and brake servo hose  connections. 
Fast idle adjustment 
Throttle  cable p? 
8. Pull the mixture  control out until  the dimension =-# 
2. 
3. 
4. 
5. 
Check  that the throttle  pedal, cable and linkage 
operate  smoothly. 
Remove 
the elbow  from the top  of the  carburetter. 
If necessary  adjust the pedal  stop bolt so :hat no 
strain  is exerted  on the  throttle  cable. Depress thc 
throttle  pedal and check  that both  the butterflies 
are  fully  open,  then adjust  the pedal  stop bolt 
so 
that it touches the floor,  without  strain on the cable  between 
the crank  in the  vertical  rod 
‘D’ and the 
underside  of the  carburetter  top cover,  without 
compressing  the spring 
‘F‘ is 12,5 mm (0.5 in). 
Adjust 
the fast  idle  screw ‘E’ so that it just makes 
contact  with 
the fast idle  cam. 
and  tighten  the locknut 
Ensure  that when  the throttle  pedal is released 
both  butterflies  are closed  completely. 
Mixture  control (cold start) 
6. Pull the mixture  control cable fully out and chcck 
that lever ‘A’ is against  its stop  and the choke  flap 
‘B’ is fully closed. If necessary  adjust the inner 
cable  clamp 
‘C’ to achieve  this condition. 
ST 1094M 
6  
						

							PETROL FUEL SYSTEM 
;$ji;! Idle adjustment ..” .. “I .7 NOTE: The idle  mixture  adjustment  screw  provides 
mixture  variation  at  idle  speed  only.  Above idle  speed 
the mixture  is determined  by fixed size jets. 
9. Start  the engine  and run until  the normal  operating 
temperature 
is attained. 
10. Turn  the throttle  butterfly  adjustment  screw to 
obtain  an idle  speed 
of 600 to 700 r.p.m. 
11. Turn  the idle  mixture  adjustment  screw clockwise 
or anti-clockwise  by one-quarter  turn increments  to 
obtain  the highest  engine 
r.p.m. When this has 
been  achieved,  re
-adjust, if necessary, the butterfly 
adjustment  screw to maintain  the 
600 to 700 r.p.m. 
idle speed. 
12. Fit the air intake  elbow to the carburetter  top. 
19 
... , , .. .. .. 1.. ..... .:.:, 
,. -. 
ST1095M .. 
V8 ENGINE  ZENITH - CARBURETTER 
OVERHAUL 
DISMANTLE 
Remove the piston assembly 
1. Remove  the carburetters  from the engine. 
2. Release  the four  screws  and withdraw  the top  cover 
3. Withdraw  the air valve,  shaft and diaphragm 
4.  Remove  the metering  needle retained  by 
a locking 
5. Release the four screws  and separate  the 
and 
spring. 
assembly 
. 
screw. 
diaphragm 
from the  air valve. 
Remove the float chamber 
6. Release the six  screws  and remove  the float 
7. Release the float  assembly  and spindle  from the 
8. Unscrew  the needle  valve and washer from 
chamber  and joint  washer. 
two  clips. 
carburetter  body. 
Dismantle carburetter  body 
9. Make location marks, as illustrated, to assist 
correct  asscmbly,  on the 
throttlc buttcrfly, spindlc 
and  carburetter  body. 
10. Right-hand  carburetter Release the two  screws  and 
remove  the butterfly  and withdraw 
thc spindlc. 
ST1119M 
1 1. Left-hand carburetter Remove the iefi-iiand iever 
assembly.  Release the two  screws,  remove  the 
butterfly  and withdraw  the spindle. 
12.  Left-hand  carburetter Release  the two  retaining 
screws  and shake
-proof  washers  and remove  the 
cold  start  assembly  and 
joint washers. 
continued 
7  
						

							I19 I PETROL FUEL SYSTEM 
8  
						

							PETROL FUEL SYSTEM 1191 
.. , .:* . ,.I. /.I.._ .. 2, ‘ ... ,.. . ... . 
L- 0 Y v) - m 0 v) 
13. Dismantle the cold  start  assembly  but DO 
14. If necessary,  dismantle the throttle  spindle lever 
NOT 
remove  the discs  from  the spindle. 
assemblies  from both carburctters. 
Y 2 
e E1 
m U 
-U C m Slow-running  adjustment  screws 
Do not  attempt  to remove  these screws or break  the 
tamper
-proof  seals. See Cautionary  note under  ‘Tune 
and  Adjust’. 
3ex 
Remove  temperature compensator 
15. Release  the two  screws  and withdraw  the 
temperature  compensator 
unit complete. 
16. Remove the large and small  rubber  washers. 
CLEANING AND INSPECTION 
h rc rc 0 W v 
Cleaning 
17. When clcaning fuel passages  do not use metal  tools 
(files,  scrapers,  drills etc.) which  could 
cause 
dimensional  changes in the drillings or jets. 
Cleaning 
of all  components  should be effected 
using  clean fuel and,  where  necessary,  a 
moisture- 
free air blast. 
; 2 U m M C C m 0 
.- .- * 
0 -0 C R 
- 
.- VI 
Joint  washers  and seals 
18. New gaskets and seals  should  be used  throughout 
carburetter  rebuild. 
A complete sct of gaskets  is 
available  for replacement  purposes. 
Inspect  metering  needle; 
it is machined  to very 
close  limits  and should  be handled 
with care. 
Examine  for wear,  bend and twist;  renew 
if 
necessary. 
19. Examine  the faces for deep scores  which would 
lead  to leakage  taking place when  assembled. 
Diaphragm 
20. Examine  the diaphragm  for deterioration,  damage 
and  punctures.  Do not  use  any  cleaning  chemicals 
on the diaphragm  only clean  lint free  rag. 
0 > m > 
- 
L- m .- 
09 
3 2 :: 
v) 3 2 x 
Float assembly 
21. Examine  the two  plastic  floats and check for 
22. Check the spindle  and retaining  clips for wear. 
23. Inspect  the needle  valve assembly  for wear.  Renew 
the  valve 
if there  is any  tendency  for the needle to 
stick.  punctures 
and damage. 
Cold  start  assembly 
24. Examine all the cold  start  components  for wear  and 
corrosion  and the machined  faces for scores. 
O”.k .k t-bQ .. 
continued 
9  
						

							1191 PETROL FUEL SYSTEM 
ASSEMBLE CARBURETTERS 
Cold  start 
- L.H.  carburetter 
25. Place  the spring on the  cold  start  spindle. 
26. 
Fit the  spring  retaining  clip. 
27.  Check that 
the discs  slide easily on  the spindle. 
28. Place  the cold  start  spindle on  the starter  face. 
29.  Place 
the starter cover  in position. 
30. 
Fit the return  spring over the  spindle. 
31.  Rotate  the  spindle until the oval  port 
in the end 
disc is aligned with  the oval port in the starter  face. 
32. 
Fit the  cold  start lever. 
33.  Engage 
the return  spring over the lug on the  starter 
cover  and the back 
of the cold  start lever. 
body. 
34. 
Place  the cold  start  gasket  onto the carburetter STl120M 
35. Fit ;he cold start  assembly  to the carburetter body, Throttle  spindle, R.H. carburetter and check  for ease of operation. 
45.  Place return spring over threaded  end  of the 
46. Fit the throttle stop  and fast idle lever. 
47. 
Fit the  bushed washer, bush  outwards. 
48. 
Fit the throttle  lever on the bushed washer. 
49. 
Fit the  plain  washer. 
50. Fit the tab  washer. 
5 
1. Fit the throttle adjust,ment lever. 
52. Secure  the assembly with the  nut and  lock  with  a 
tab. 
53.  Fit 
thc throttle  butterfly as described  in instruction 
39  and  anchor  the  return  spring  as illustrated.  See 
note  before instruction 39. 
spindle. 
ST1116M continued 
Throttle 
spindle, L.H.  carburetter 
36. Place  the  return  spring  over  either  end of the 
spindle. 
37. 
Fit the  throttle  stop and fast idle lever  and  secure 
with spacers, tab washer and nut. 
38.  Insert 
the throttle  spindle from the cold  start  side 
of the  carburetter  body and 
fit the throttle  return 
spring  on the  fast  idle  adjustment  lug. Tension  the 
spring  half 
a turn. 
NOTE:  Slacken  the idle  adjustment  screw  clear  of 
lever to facilitate centralisation  of the  butterfly. 
39. Fit the  throttle  butterfly,  maintaining the 
previously marked alignment.  Leave  the  retaining 
screws loose.  Actuate  the throttle several times 
to 
centralize  the butterfly,  then tighten the retaining 
screws  and lock  by peening ends. 
40. E: the thr=tt!e !eve: tc the spind!e at the ~pi;c~:te 
end. 
41. Place the spacer on  the spindle. 
42. Place the  tab washer on the  spindle. 
43. 
Fit the sleeve  nut, sleeve  end  last,  and  engage  the 
44. 
Fit the throttle adjusting  lever. 
10 
s51: Y.& 51 
ST1121 M 
tab washer.  
						

							PETROL FUEL SYSTEM 119 
Float chamber assembly 
54. Fit the needle valve and new  washer. 
55. Locate the spindle in the float  arm  and fit the 
assembly  into the retaining  clips. 
seating  and 
thc float tab is contacting  the  needle. 
Measure  the dimension 
A between the carburetter 
gasket  face and 
the highest  point on the floats.  The 
correct  measurement  should be 17 to 
18 mm (0.67 
to 
0.71 in).  Adjust  by bending the float  tab. This 
dimension  must  be  the same  for both  floats.  The 
float  carrier  tab must  be maintained  at  right  angles 
to  the needle 
in the  closed position. 
57. 
Fit the  float  chamber  and new  gasket  and  evenly 
tighten  the retaining  screws. 
56. Invert the  carburetter so that  the  needle  is on  its 62 
- .. .. .. . .. 
ST1123M 
Air valve  and diaphragm 
58. Fit the diaphragm  to the air valve with  the inncr tag 
locating  in the  air valvc recess. 
59. 
Fit the  diaphragm  retaining ring and  secure  with 
the four screws. 
60. Fit the  metering needle into the air v2!ve and 
secure  with the locking  screw. 
61. Insert the air valve  and needle into the carburetter 
and  locate 
the diaphragm  outer tag  into  the recess 
in the carburetter  body. 
62. Fit the spring  and top cover  and secure  with the 
four screws. 
63. 
Fit the  damper. 
---- ST7 1 17M 
Temperature compensator 
64.  Clean  the  carburetter  and compensator  mating 
faces. 
65. Fit a new  inner and  outer rubber  washer and securc 
the  temperature compensator  with thc two  screws 
and shake
-proof washers. 
Fast idle adjustment - L.H. carburetter only 
66.  Slacken  the fast idle adjusting  screw. 
67.  Hold  the cold  start  cam  lever 
in the  maximum 
position. 
68.  Adjust 
thc fast idle  adjusting  screw against  the cam 
lever  until there  is 
0,61 to 0,66 mm (0.024 to 
0.026  in) gap  between 
the top edge  of the  throttle 
butterfly  and 
the carburetter  barrel wall. Use feeler 
gauges 
or a 0,65 mm diameter (No. 72)  drill  to 
measure  the gap. 
69.  Secure the  locknut on  the fast  idle  adjusting  screw 
without disturbing  the adjustment. 
11  
						

							I 19 I PETROL FUEL SYSTEM 
V8 ENGINE ZENITH CARBURETTERS 
TUNE AND ADJUST 
Tamper
-proofing 
These  carburctters  may be externally  identified by a 
tamper
-proof  sealing  tube fitted  around  the slow 
running  adjustment  screw. 
The  purpose  of these  carburetters  is to  more  stringently 
control  the air fuel  mixture  entering  the engine 
combustion  chambers and, in consequence,  the exhaust 
gas  emissions  leaving 
the engine. 
For this reason  the only  readily  accessible  external 
adjustment  is to  the  throttle  settings for idle  and  fast 
idle  speed  and, for the  former  setting 
will require  the 
use 
of a  special  tool to prevent  breaking  the tamper- 
proof  seals. 
* CAUTION:  Unauthorised  breaking of tamper-proofing 
devices,  adjustment  of carburetter  settings 
or the fitting 
of  incorrectly  related parts may render  the vehicle  user 
liable  to legal  penalties  according  to local  territory 
legislation. 
Whenever  adjustments  are made  to the  settings  of 
tamper
-proof  or emission  specification  carburetters an 
approved  type CO meter  must be used  to ensure  that the 
final  exhaust  gas analysis  meets with local  territory 
requirements. 
Emission  Specifications 
All carburetters  fitted to the  Land-Rover  conform  at 
the time of manufacture  to particular  territory 
requirements 
in respect  of exhaust  and evaporative 
emissions  control. However,  in some  cases changes  to 
the  basic  carburetters  may have  been necessary  to 
achieve  this. 
Service  tools: 
605330 - Carburetter  balancer 
MS80 - Mixture adjusting  tool 
MS86 
or B25243 - Tamper-proofed  throttle 
adjustment  tool 
The  service  tool 
605330 carburetter  balancer must be 
used  to adjust  the carburetters.  Primarily, this 
instrument  is for  balancing  the air
-flow  through  the 
carburetters,  but it also  gives  a good  indication 
of the 
mixture setting.  Investigation  has shown  that incorrect 
mixture  setting causes either stalling  of the  engine 
or a 
considerable  drop in engine rev/min if the  balancer  is 
fitted  when  the mixture 
is too  rich  or a considerable 
increase 
in rvt (anin when  used wit;] tule mixture  setting 
too  weak. 
Br\)re balancing  the  carburetters  it is  most 
important  therefore that the following  procedure  be 
carried  out: 
Slow running  (idle) adjustment 
1. Check  that the throttle  control between  the pedal 
and  the carburetters  is free  and has no tendency 
to 
stick. 
2. Check  the throttle  cable setting  with the throttle 
pedal 
in the  released  position.  The throttle  linkage 
must  not have  commenced  movement, but 
commences  with the minimum  depression  of the 
pedal. 
3. Run  the engine  until it attains  normal  operating 
temperature;  that is, thermostat  open. 
4.  Remove 
the air  cleaner  elbows. 
5.  Slacken  the screws  securing  the throttle  adjusting 
levers  on both  carburetters  to allow  independent 
adjustment. 
r . 
$,;; 
6. 
7 
Start  the engine  and check  the idle  speed  using a 
reliable  proprietary  tachometer. 
If necessary, adjust the slow running  screw to give 
the  correct  idle speed,  see Engine  tuning data. If a 
tamper
-proof  sleeve  is fitted  over this screw  the 
slow  running  speed can 
only be adjusted  using 
special  tool MS86 
or B25243. $3, .._ : -r C. 
continued 12