Land Rover Defender Workshop 1993 Rover Manual

							AIR CONDITIONING  
						

							AIR CONDITIONING  
						

							AIR CONDITIONING 
CHARGING AND TESTING  EQUIPMENT 
Connecting  the gauge  set 
NOTE:  1: 
There  are  two methods of connecting 
the  charging  and testing  equipment,  depending 
on  the  operation  to be  carried  out. The  method 
described  for evacuating 
or charging  with liquid 
refrigerant  also  applies to pressure  test  and 
compressor  oil level check  operations. 
NOTE: 2: Various  types of charge  and  test 
equipment  are available  depending  upon the 
manufacturer  chosen by the  user.  The equipment 
illustrated  may differ  slightly 
in layout  to that 
possessed  by 
t he user,  however,  it is 
recommended  that the user  adheres  to the 
appropriate  manufacturers  instructions  for  the 
charge  and  test equipment  used in their  8. 
Put on the  safety  goggles. 
workshop. 
Fitting 
1. 
6. Place  the vehicle  in a ventilated  area away 
from  open  flames  and heat  sources.  Stop the 
engine,  open and secure  the bonnet. 
7. Check  that both  service  valves are fully  open 
(turned  anti-clockwise). 
9. Remove  the caps  from the gauge  connections 
on  the  service  ports. 
10. Coat the threads  and flares  with refrigerant oil. 
11. Connect  the low  pressure  charging line (blue) 
from  valve  No. 
1 to the  compressor  suction 
service  port. 
12.  Connect  the high  pressure  charging line (red) 
from  valve  No. 
2 to the  compressor  discharge 
service  port. 
13.  Using  the service  wrench,  turn the suction 
service  valve stem clockwise  counting the 
number  of turns  necessary  to close  the valve. 
Ensure 
that all the  valves  on the  charging  and 
testing  equipment  are closed.  Control  valves 
on  the  particular  equipment  selected are 
numbered 1 to 4 as  illustrated.  The sequence 
may  vary  on other  proprietary  equipment. 
2.  Mount  a 11,3  kg drum  of refrigerant  upside 
down  on the  support  at the  rear 
of the 
charging  equipment,  and secure  with the 
strap. 
14. After  the valve  is fully  closed,  turn the stem 
out  (anti
-clockwise)  half the number  of turns 
counted,  this should  position  the valve  seat in 
the  mid  {test)  position. 3. Connect  the hose  from the bottom of the 
charging  cylinder 
to the refrigerant  drum valve. 
4. Connect  the hose  between  the bottom of the 
charging  cylinder and the refrigerant  control 
valve  (No. 4). 
5. Connect  the hose  between  the vacuum  pump 
valve  and the vacuum  control valve (No.3). 
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							AIR CONDITIONING 
15. Turn  the stem  on the  discharge  valve 1. Place the vehicle  in a ventilated  area away 
clockwise  until the pressure  rises on the  from open  flames  and heat  sources. 
discharge  pressure gauge, 
If the system  is to 
be  evacuated,  the discharge  service valve 
3. Open and secure  the bonnet. 
seat  must  be in the  mid  (test)  position. 
4. Remove  the caps  from the compressor 
connected  and ready  for proceeding  with the 
5. Check  that both  compressor  service valves 
required  operation.  are 
fully  opened  (turned anti
-clockwise). 
6. Close all valves  on the  charging  and testing 
7.  Put on safety  goggles. 
17. 
If the  engine  has been  operated, it must  be 8. Connect  the high  pressure  charging line (red) 
stopped  prior to disconnecting  the charging  from valve  No. 2 to  the  compressor  discharge 
and  testing  equipment.  service port. 
18. Close  both service  ports (turn fully 9. Run the (blue)  hose to an  open  tapped 
anti
-clockwise)  until fully closed.  container 
of approximately  one litre capacity. 
19. Close  all valves on the  charging  and testing  Attach 
the hose  to the  container so that it will 
equipment. not blow  out of the  container.  The purpose  of 
20.  Disconnect  the charging  lines from the service  the 
container  is 
to collect any oil carried  by 
ports.  the refrigerant. 
21.  Refit  the blanking  caps to the  compressor 
10. Open  the compressor  discharge service port a 
valve  stems  and service  ports, and to the  quarter 
of a turn. 
charging  lines.  11. 
Open  valve No. 2 fully. 
2. 
Stop  the engine. 
16.  The charging  and testing  equipment  is now  service ports. 
Removing equipment. 
22. Close the bonnet. 12. Slowly  open the valve  No. 1 one  turn  to allow 
the  refrigerant  to escape,  if necessary,  adjust 
the  refrigerant  flow 
so that the oil captured  in 
the  container  is not  blown  out of the  container. 
AIR  CONDITIONING  SYSTEM OPERATIONS 
Depressurising 
NOTE: 
The  air conditioning  refrigeration system 
contains  Refrigerant  12 under  pressure,  and 
before  any component 
is disconnected  or 
removed,  the system  must be discharged 
of all 
pressure. 
Refrigerant 
12 evaporates so rapidly  at normal 
atmospheric  pressures and temperatures  that  it 
tends  to freeze  anything  it contacts.  Extreme 
care  must  be taken  to prevent  any liquid 
refrigerant  from contacting  the skin  and 
especially  the eyes.  Should  any liquid  refrigerant 
get  into  the eyes,  use a few  drops  of sterile 
13. Measure  the amount  of 
oil discharged  from 
mineral  oil to wash  them out and  then  wash  the  the system 
so that  an equal  amount  of new  oil 
eyes  with 
a weak  solution  of boric  acid. Seek  can be returned  to the  system  during the 
medical  attention  immediately  even though  the  charging operation.  Discard the old 
oil. 
initial  irritation  has ceased  after first aid 14. When  the gauge  pressure  is below  50 psi, 
treatment.  Always wear safety  goggles  when 
slowly open the valve  No. 
1 to maintain 
opening  refrigerant  connections.  refrigerant flow. 
15. When the pressure  has been  reduced,  and WARNING: Open connections  slowly, keeping the the system  has been  completely  discharged, 
hands 
and face  well clear, so that  no injury  close the valves  Nos. 1 and 2 on  the  charging 
occurs 
if there  is liquid  in the  line. If pressure  is  and testing  equipment. 
noticed  allow it to  bleed  off slowly. 
16. Close  the compressor  discharge service port 
(turn  anti
-clockwise). 
17. Disconnect  the high  pressure  charging line 
from  the compressor  service port. 
12  REISSUED: 
FEB 1993  
						

							AIR CONDITIONING 
NOTE: If it is necessary  to disconnect  the 1. Depressurise  the air conditioning  system as 
compressor  hoses, the compressor  should be previously  described,  then connect  the gauge 
sealed  by fully  closing  the relevant  service valve set as detailed  under Charging  and Testing 
(turn  fully clockwise).  It is essential  to ensure Equipment. 
that  both  service  valves are open  before 2. Adjust  both service  valve seats to the mid 
operating  the compressor.  Similarly any other (Test)  position. 
component of the refrigeration  system should be 3. Open  the low  and  high  pressure  valves Nos. 1 
capped immediately  when disconnected. and 2. 
4. Start  the vacuum  pump and check  that the 
vacuum  pump valve is open. 
5. Slowly  open the vacuum  control valve No. 3. 
If the vacuum  is applied  to the  system  too 
quickly,  the residual  oil may  be drawn  out. 
18. 
Open  the refrigeration  drum valve. 
19. Open  the valve  at the  base of the charging 
cylinder  and allow  approximately  0,25 kg of 
refrigerant  to enter  the cylinder. 
20.  Close  the refrigeration  drum valve  and the 
valve  at the  base  of the  charging  cylinder. 
21.  Open  the refrigerant  control valve (valve 
No. 
4) and  flush  out the  high  and low pressure 
lines  by opening  valves Nos. 1 and  2 
momentarily  until a white  stream  of refrigerant 
is  observed. 
6. 
In evacuating the system it is necessary  to 
lower  the pressure 
so that  the boiling  point of 
water  in the  system  is lower  than the 
surrounding  air temperature. 
At an  ambient 
temperature 
of 23.8°C  (75°F), it is necessary 
to  lower  the system  pressure  to 
29.5 in Hg 
vacuum  to bring  the boiling  point of water  to 
22.  Close  all valves  on the  charging  and testing  22°C (72°F).  Atmospheric  pressure (and 
vacuum  gauge  readings) decrease as altitude 
23. The  air conditioning  system is now  increases by approximately  25 mm  Hg per 
300  m. The  following  chart provides  a guide  to 
the  various  gauge readings  at differing 
altitudes,  for the  same 
10 mm  Hg absolute 
equipment, 
and fit the  blanking  caps. 
depressurised. 
Evacuating pressure. 
Whenever  the system  has been  opened  to the 
Altitude,  ft m Vacuum Reading in Hg  mm 
atmosphere  it is  necessary  that the system  be 0 0 29.5  750 
evacuated  to remove  all air  and  moisture. 
It is also 1,000 300  28.5  725 
an  essential  preliminary  operation to charging  the  2,000 
600 27.4 695 
system 
with Refrigerant  12. The  evacuate  operation  3,000 
900  26.4  670 
also  provides  a check  for leaks  due to faulty 
4,000 1200  25.4 645 
connections. 5,000 1500 24.5  622 
6,000 1800 23.5 596 
7,000 2100 22.6  574 
8,000 2400 21.8 554 
9,000 2700 20.9 530 
10,000 3000 
20.1 510 
REISSUED: FEB 1993 13  
						

							AIR CONDITIONING 
7. The  low  side  gauge should indicate a  vacuum Sweeping 
of 660 mm  Hg within  five  minutes. 
8. Whilst the system is evacuating,  fill the NOTE: This  operation  is in addition to 
charging  cylinder  by  opening  the  refrigerant evacuating, and is  to  remove  moisture  from 
drum  valve. 
systems that have  been  open 
to atmosphere  for 
9. Open  the valve  at the  base  of the  charging  a long period, or that are known  to contain 
cylinder  and fill the  cylinder  with 1,0 kg  of  excessive moisture. 
refrigerant.  Liquid refrigerant 
will be  observed 
rising  in the  sight  glass. 
1. Fit  a new  liquid  receiver/drier,  as detailed 
open  the valve  at the  top of the  cylinder  2. 
Ensure  that  a full  drum  of refrigerant  is fitted 
(behind  the control  panel) intermittently, 
to on the  charging  and testing  equipment. 
relieve  the  head  pressure  and  allow the  3.  Fit the  charging  and testing  equipment  as 
refrigerant 
to continue filling  the cylinder.  previously described for evacuating  and 
11. When the  refrigerant reaches  the desired  level  evacuate  the  air  conditioning system,  allowing 
in  the  sight  glass,  close  both the valve at the  0,25 
to 0,45 kg of refrigerant to enter  the 
base  of the  cylinder  and  the valve  at the  charging  cylinder. 
bottom of  the refrigerant  tank.  4. 
Close 
all valves  on the  charging  and  testing 
12.  Ensure 
the  top  cylinder  valve  is fully  closed. 
If equipment. 
bubbling  is  present  in the  sight  glass,  reopen  5. 
Disconnect  the  intake hose  from the vacuum 
equalise  the drum  and cylinder  pressures. 
13. 
If 660 mm  Hg  of vacuum  is not  achieved 
within  five  minutes,  it signifies  either the 
system  has  a leak 
or the vacuum  pump is 
defective.  Initially  check the vacuum  pump, if 
the  pump  proves 
to be functioning  properly 
then  investigate  for a leak  in the  air 
conditioning  system. 
14. Close the vacuum  control valve No. 3. 
15. Stop the vacuum  pump  and  allow  the  vacuum 
to hold for fifteen  minutes,  then  check  that 
there  is  no  pressure  rise (a 
loss of vacuum) 
evident  on the  compound  gauge. Any 
pressure  rise  denotes  a  leak  which  must  be 
rectified  before proceeding  further.  Refer 
to 
the  heading titled ’Leak  Detection’ later  in this 
section. 
16.  With  the system  satisfactorily  evacuated,  the 
system  is ready  for charging with  refrigerant. 
10. As the  refrigerant  stops filling  the  cylinder,  under the  heading  “Receiver/Drier”. 
the  cylinder  base valve  momentarily 
to pump. 
6. Connect  the  intake  hose to the valve  at the 
top  of the charging  cylinder. 
7. Open  the  valve  at the  top  of the  charging 
cylinder. 
8. Put  on safety  goggles. 
9. Crack  open  the hose  connection  at valve No. 
3 and  allow  some  refrigerant to purge the 
hose,  then  close the  connection. 
10.  Open the  high pressure valve  (No.2). 
11. Slowly open  valve  No. 3, which is now 
connected 
to the  top valve  of the  charging 
cylinder,  and allow  gas 
to flow into the  system 
until  the  reading  on the  compound  gauge 
remains  steady,  Between  0,25 and 0,45  kg of 
refrigerant will  enter  the system. 
12.  Allow  the dry  refrigerant  introduced  into the 
system 
to remain  for 10 minutes. 
14 
REISSUED: FEB 1993  
						

							AIR CONDITIONING 
13. Crack the suction  valve charging  line at the 6. If the full charge of 1,09 kg of liquid  refrigerant 
service  port on the  compressor  to allow  an  will not enter  the system,  then close  the high 
escape  of refrigerant,  at the  same  time  pressure valve (No.2)  and open  the 
low 
observing  the sight  glass in the charging  pressure  valve No.1), ensuring that the low 
cylinder, 
A slight  drop in the  level  should  be 
allowed  before closing  the connection  at the 
7. Start  and run the engine  at 1,000 -1,500 
compressor.  rev/min and allow  refrigerant  to be  drawn 
14.  Close  the high  pressure  valve (No.2).  though 
the low  pressure  valve (No. 1) until  the 
15. Close  valve No.3. full charge  has been  drawn  into the system. 
16. Close  the valve  at the  top of the  charging  8. Close  valve No.1. 
pressure 
gauge does not exceed  18.14 kgf². 
cylinder. 
9. Check  the air conditioning  system is operating 
17.  Reconnect  the charging  and testing  satisfactorily by carrying 
out a pressure  test, 
as  described  later in the  Section 
equipment, 
as described  for evacuating  and 
evacuate  the air conditioning  system. 
18.  Maintain  the vacuum  for twenty  minutes.  The 
CAUTION: Do not overcharge  the air conditioning 
air  conditioning  system is now  ready  for system  as this will cause  excessive  head 
charging with refrigerant. pressure. 
Charging  Leak test 
CAUTION: 
Do not  charge  liquid refrigerant  into 
the  compressor.  Liquid cannot 
be compressed; 
and 
if liquid  refrigerant  enters the compressor sensitive  and widely  used. 
inlet valve,  severe  damage  is possible;  in 
addition,  the oil charge  may 
be absorbed  into the 1. Place  the vehicle  in a well  ventilated  area but 
refrigerant,  causing damage when the free from  draughts,  as leakage  from the 
compressor  is operated. system  could be dissipated  without detection. 
2.  Follow  the instructions  issued by the 
1. Fit the  charging  and testing  equipment  as  manufacturer  of the  particular  leak detector 
previously  described for evacuating.  being 
used. Certain  detectors  have visual  and 
2.  Evacuate  the air conditioning  system allowing  audible indicators. 
1,09 kg of refrigerant  to enter  the charging 3. Commence  searching for leaks  by passing  the 
cylinder.  detector probe around  all joints  and 
3. Put on safety  goggles.  components, 
particularly on the  underside,  as 
4.  Close  the low  pressure  valve 
(No.1). the refrigerant  gas is heavier  than air. 
5. Open  the refrigerant  control valve (No. 4) and  4. Insert  the probe  into an air outlet  of the 
release  liquid refrigerant  into the system  evaporator. Switch the air conditioning  blower 
through  the compressor  discharge valve port  on and 
off at intervals of ten  seconds. Any 
(High  pressure).  The pressure  in the  system  leaking refrigerant  will be gathered  in by the 
will eventually  balance.  blower and detected. 
The 
following  instructions  refer 
to an electronic  type 
refrigerant  leak detector  which is the  safest,  most 
REISSUED: FEB 1993 15  
						

							AIR CONDITIONING  
						

							AIR CONDITIONING 
COMPRESSOR COMPRESSOR DRIVE BELT 
Remove  Adjust 
1. Site vehicle  in a ventilated  area. 1. Slacken  idler pulley  securing  bolt. 
2.  Disconnect  the battery  negative lead. 
3.  Discharge  the  air  conditioning system, see 
Discharging  system 
WARNING: Wear eye and  hand  protection  when 
disconnecting  components containing 
refrigerant.  Plug all exposed  connections 
immediately. 
4.  Disconnect  suction and discharge  unions  from 
compressor. 
5. Disconnect  electrical lead to compressor 
clutch. 
6. Slacken idler pulley  and release  drive belt. 
7. Remove  the  two  compressor  mounting  bolts 
and 
lift compressor  clear.  2. Adjust  positron  of idler  pulley  until  correct 
tension 
is obtained.  The belt must  be  tight 
with  4 to 
6 mm total  deflection  when checked 
by  hand  midway  between  pulleys on the 
longest  run. 
3. Tighten  securing  bolt  and  recheck tension. 
CONDENSER  FAN MOTORS 
Removal 
1. Open and  secure the bonnet. 
2.  Release  the  six self  tapping  screws  securing 
the  front  nose  and grille  assembly,  lift clear. 
3.  Disconnect the  electrical leads 
to the fans. 
4.  Remove  the  blanking caps 
from the fan 
centres. 
Refit 5.  Remove  the  8 mm securing  nuts,  star and 
spring  washers 
from the fan  blade  centres, 
pull blade  from its respective fan  motor shaft. 
6.  Release the 
two fan motor  retaining  bolts and 
remove  the  motor  whilst feeding  the  fan motor 
through  the appropriate  aperture. 
8. 
If a 
new  compressor  is being  fitted,  drain  oil 
from  new compressor.  Drain  and  measure  oil 
from  old compressor.  Add 
30 ml of new  oil to 
this amount  and refill  new compressor. 
9. Locate  compressor  in position,  fit and  tighten 
mounting bolts. 
10. 
Fit compressor  drive  belt, see Adjustment, 
Compressor  drive belt 
11.  Connect  electrical  lead  to  compressor clutch 
at  the  connector. 
12.  Evacuate  air  conditioning  system. See 
Evacuate  system. 
13.  Charge  air conditioning  system.  See 
Charging  system. 
7. Reverse procedures 1 to 6 ensuring  the  fan 
supply  wiring is routed  and  securely  clipped 
so  that  the wiring  does 
not foul the  fan  blades 
REISSUED: FEB 1993 17