Page 268 of 284
24-32 AIR-CONDITIONING-Service Adjustment Procedures
i--
9 >
@
r
2ouo319
- 2OW627 I
Suction gauge Discharge w-w
/ I
Suction
ww Discharge
w-w
2OUO306
Suction
w-w Discharge
gauge
2OUO307
AIR CONDITIONER SWITCH
To jest the Air Conditioner Switch
(1) Disconnect the harness connector for the air conditioner
switch.
(2) Jump the lead wires as shown.
(3) Turn the blower switch ON.
(4) Momentarily turn the ignition switch on (do not crank the en-
gine), listen for the clutch engaging.
(5) If the clutch does not engage, fin thermostat, water
temperature switch, wiring or fuse may be faulty.
(6) If clutch engages, replace the air conditioner switch.
MAGNETIC CLUTCH
(1) Disconnect the wiring to the magnetic clutch.
(2) Connect battery (+) voltage directly to the wiring for the mag-
netic clutch.
(3) If the magnetic clutch is normal, there will be a “click”. If the
pulley and armature do not make contact (“click”), there is a
malfunction.
COMPRESSOR
(1) Install the manifold gauge set, and run the air conditioner.
(2) If a pressure of approx.490 kPa (71 psi) is indicated on the
suction gauge side and a pressure of approx.883 kPa (128 psi)
is indicated on the discharge gauge side, the compressor has
abnormal compression.
Replace the compressor.
(3) If a pressure of 294 to 392 kPa (43 to 59 psi) is indicated on the
suction gauge side and a pressure of approx.1961 kPa (284
psi) is indicated on the discharge gauge side, it is suspected
that air is present in the air conditioning system.
Discharge the system, evacuate and recharge with specified
amount of refrigerant.
(4) During operation of the air conditioner, cold air may stop flow-
ing after the elapse of time and this state is maintained before
cold air flows out again. If cold air stops flowing out with
negative pressure indicated on the suction gauge side and a
pressure of 588 to 980 kPa (85 to 142 psi) indicated on the
discharge gauge side, it is suspected that water is present in
the air conditioning system.
Discharge the system. Replace receiver drier. Evacuate and
check for leaks, and recharge with specified amount of refrig-
erant.
/ STB Revision
Page 270 of 284
24-34 AIR-CONDITIONING-Service Adiustment Procedures
r---- :
:ES
Dry bulb therr&neter
2OW825
PEAFORMANCE TEST
TESI N24FWAB NOTE
Air temperature in test room must be 21°C (70°F) minimum for this
test.
(1) Connect a tachometer and manifold gauge set.
(2) Set air conditioner controls to Max air conditioner, tempera-
ture lever on full cool, and blower on high.
(3) Turn engine on 1000 rpm with air conditioner clutch engaged.
(4) Engine should be warmed up with doors, windows, and hood
open.
(5) Insert a thermometer in the left center air conditioner outlet
and operate the engine for 5 minutes.
(6) Note the discharge air temperature.
NOTE
If the clutch cycles, take the reading before the clutch disen-
gages.
Performance Temperature Chart Garage ambient
temperature
21 “C 26.5 “C 32 “C 37.5 “C 40.6 “C (70 “F) (80 “F) (90 “F) (100 “F) (I 05 “F)
Discharge air
temperature
Compressor
discharge pressure
Evaporator suction
pressure
1.7-4.4 “C 1.7-5.0 “C 1.7-5.6 “C 1.7-6.1 “C 1.7-6.7 “C (35-40 “F) (35-41 “F) (35-42 “F) (35-43 “F) (35-44 “F)
928- 1,322 kPa 1.069-1.547 kPa 1,209-1,772 kPa 1,336-1,969 kPa 1,406-2,109 kPa
(132-188 psi) (152-220 psi) (172-252 psi) (190-280 psi) (200-300 psi)
127-148 kPa
131-162 kPa 134-176 kPa 135- 188 kPa 136-194 kPa
(18-21 psi) (18.6-23 psi) (19-25 psi) (19.2-26.8 psi) (19.4-27.6 psi)
REFRIGERANT LEAK REPAIR PROCEDURE N24FnAB
LOST CHARGE If the system has lost all charge due to a leak:
(1) Evacuate the system. (See the procedure).
(2) Charge the system with approximately one pound of refriger-
ant.
(3) Check for leaks.
(4) Discharge the system.
(5) Repair leaks.
(6) Replace receiver drier.
Caution
Refrigerant
leak tester
Replacement filter-drier units must be sealed while in stor-
age. The drier used in these units will saturate water quickly
upon exposure to the atmosphere. When installing a drier,
have all tools and supplies ready for quick reassembly to
avoid keeping the system open any longer than necessary. (7) Evacuate and charge the system.
LOW CHARGE If the system has not lost all of its refrigerant charge; locate and
tester repair all leaks. If it is necessary to increase the system pressure
up to find the leak (because of an especially low charge) add refrig-
erant. If it is possible to repair the leak without discharging the
refrigerant system, use the procedure for correcting low refriger-
2OUO316 ant level.
1 STB Revision
Page 280 of 284
24-44 AIR-CONDOTIONING-Evaporator
DISASSEMBLY AND REASSEMBLY
1
Disassembly steps
1. Air conditioner relay
2. Thermostat
3. Screw
4* 4. Clip
5. Evaporator case (upper)
6. Evaporator case (lower)
7. Evaporator assembly
+e l + 8. Expansion valve
NOTE
(1) Reverse the disassembly procedures to reassemble.
(2) +e : Refer to “Service Points of Disassembly”.
(3) l + : Refer to “Service Points of Reassembly”.
N24RE-- -6
2OW828
2OW718
2ow722
a 0-rina
Expansion
valve
O-rim
SERVICE POINTS OF DISASSEMBLY
4. REMOVAL OF CLIP
N24RFAB Remove the clips with a flat-blade screwdriver covered with a
shop towel to prevent damage to case surfaces.
8. REMOVAL OF EXPANSION VALVE Use two wrenches to loosen the flare nut on the pipe con-
nection (for both the inlet and outlet).
SERVICE POINTS OF REASSEMBLY N24RHAE
8. APPLICATION OF COMPRESSOR OIL TO EXPANSION
VALVE Apply specified compressor oil to the O-rings and install
the expansion valve to the evaporator assembly.
Specified oil : DENS0 oil 6
1 STB Revision