1987 MAZDA 626 Workshop Manual

16 COOLING UNIT
COOLING UNIT
ON-VEHICLE INSPECTION OF EXPANSION
VALVE
1. Connect the manifold gauge set to the gauge fit-
tings on the low- and high-pressure pipes.
2. Operate the engine at 1,500 rpm and the air con-
ditioner at MAX. COOLING.
3. Check the low and high pressures.
Normal pressures are:
Low: 197—294 kPa
(2—3 kg/cm2, 28—43 psi)
High: 1472—1765 kPa
(15—18 kg/cm2, 210—260 psi)
If pressure is not as specified, replace the expansion
valve.
76G16X-623
REMOVAL OF COOLING UNIT
1. Disconnect the battery ground cable.
2. Discharge the air conditioning system. (Refer to page 16—9.)
3. Disconnect the suction low-pressure pipe from the evaporator unit outlet fitting.
4. Disconnect the liquid line pipe from the evaporator unit inlet fitting.
Note:
Plug all open fittings immediately to keep moisture out of the system.
5. Remove the grommets from the expansion valve.
6. Remove the instrument lower panel and the glove box.
7. Remove the sealing plates from both sides of the cooling unit.
8. Disconnect the A/C wiring harness from the evaporator unit.
9. Remove the drain hose from the cooling unit.
10. Remove the two nuts and the cooling unit.
76G16X-624
16-26

COOLING UNIT 1 6
Upper case Expansion valve / Thermostat
Lower case
76G16X-006
DISASSEMBLY OF COOLING UNIT
1. Remove the screws by using a screwdriver.
2. Remove the upper case.
3. Remove the thermostat.
4. Remove the lower case.
5. Remove the expansion valve.
INSPECTION OF EVAPORATOR
1. Check the evaporator fins for blockage. If the fins
are clogged, clean them with compressed air.
Caution:
Never use water to clean the evaporator.
2. Check the fittings for cracks or scratches. Repair
or replace, if necessary.
ASSEMBLY OF COOLING UNIT
1. Connect the expansion valve to the inlet fitting of
the evaporator. Tighten the two bolts by using a
wrench.
Note:
Be sure that the O-ring is positioned on the
pipe fitting.
Specified torque: 2.7—3.4 N-m
(0.27—0.35 m-kg, 2.0—2.5 ft-lb)
2. Install the lower case onto the evaporator.
3. Install the thermostat in its original position.
4. Install the lower case onto the evaporator.
69G16X-060
16—27

1 6 COOLING UNIT
INSTALLATION OF COOLING UNIT
1. Install the cooling unit by using the two nuts.
Note
Adjust and position the unit so that its con-
nections match those of the heater unit and
the blower unit.
2. Connect the drain hose.
76G16X-625
Sealing plate
Heater I _ .. ' . . - V
unit Evaporator dealing plate Blower unit
3. Join the connections on both sides by using the
seal plates.
4. Connect the A/C harness to the cooling unit.
76G16X-626
76G16X-627
5. Connect the liquid line high-pressure pipe and suc-
tion low-pressure pipe to the cooling unit.
Tightening torque:
15—22 Nm (1.5—2.5 m-kg, 11—18 ft-lb)
6. Install the instrument lower panel, shower duct and
glove box.
7. If the evaporator is replaced, add compressor oil
to the compressor.
Compressor oil: 50 cc (3.05 cu in)
16-28

REFRIGERANT LINES 1 6
REFRIGERANT LINES
ON-VEHICLE INSPECTION
1. Check all piping connections for leakage by using a leak detector. Replace if necessary.
2. Check that the hose and pipe clamps are not loose.
Tighten or replace, if necessary.
REPLACEMENT OF REFRIGERANT LINES
1. Discharge the air conditioning system. (Refer to page 16—9)
2. Replace the faulty pipe or hose.
Note:
Plug all open fittings immediately to keep moisture out of the system.
Tightening torque (fittings):
Location Tightening torque
© 10—20 N m (1.0—2.0 m-kg, 7.2—14.4 ft-lb)
© 15—25 Nm (1.5—2.5 m-kg, 10.8—18.0 ft-lb)
© 20—29 Nm (2.0—3.0 m-kg, 14.4—21.6 ft-lb)
3. Evacuate, charge, and test the air conditioning system. (Refer to page 16—9.)
76G16X-628
16—29

1 6 A/C RELAY
A/C RELAY
REMOVAL OF RELAY
1. Disconnect the negative battery cable.
2. Disconnect the wire harness connector
3. Remove the relay from the seal plate.
INSPECTION OF A/C RELAY
1. Using a circuit tester, check that there is continui-
ty between terminals (a) and (b).
2. Apply 12 volts across terminals (a) and (b), and
check whether there is continuity between termi-
nals (c) and (d). Replace if necessary.
INSTALLATION OF A/C RELAY
1. Install the relay to the seal plate.
2. Connect the wire harness connector.
3. Connect the negative battery cable.
THERMOSTAT
ON-VEHICLE INSPECTION
1. Operate the air conditioner at MAX. COOLING.
2. Turn the ECO switch to ON.
3. Block the air inlet of the blower unit with a thick
piece of paper.
4. Check whether the relay is turned OFF when the
temperature of the evaporator drops below 7°C
(44.6°F).
5. Turn the ECO switch to OFF.
6. Check whether the relay's turned OFF when the
temperature of the evaporator drops below 1°C
(33.8°F).
REMOVAL OF THERMOSTAT
1. Disconnect the negative battery cable.
2. Disconnect the A/C wiring harness.
3. Remove the thermostat from the cooling unit.
INSTALLATION OF THERMOSTAT
1. Install the thermostat by using the two screws.
2. Connect the A/C wiring harness.
3. Connect the negative battery cable.
76G16X-007
16-30

REFRIGERANT PRESSURE SWITCH 1 6
76G16X-008
REFRIGERANT PRESSURE SWITCH
• Low-pressure side
If the high pressure in the system drops to below
196 kPa (2.0 kg/cm2, 28.4 psi) the switch cuts
the compressor power supply and turns on at a
pressure above 206 kPa (2.1 kg/cm2, 30.0 psi).
• High-pressure side
If the high pressure in the system exceeds 2,649
kPa (27 kg/cm2,384 psi) the switch cuts the com-
pressor power supply and turns on at a pressure
above 2,060 kPa (21 kg/cm2, 299 psi).
2.0 kg/cm2
OFF ON
2.1 kg/cm2
Low pressure side
ON
27 kg/cm2
OFF
21 kg/cm2
High pressure side
16—31

30
TECHNICAL DATA
MEASUREMENT 30— 2
ENGINE (SOHC) 30— 2
ENGINE (DOHC) 30— 8
ENGINE (DIESEL) 30—11
LUBRICATION SYSTEM (GASOLINE) 30—14
LUBRICATION SYSTEM (DIESEL) 30—15
COOLING SYSTEM (GASOLINE) 30—16
COOLING SYSTEM (DIESEL) 30—17
FUEL AND EMISSION CONTROL SYSTEM
(CARBURETOR) 30—18
FUEL AND EMISSION CONTROL SYSTEM
(FUEL INJECTION FE) 30—20
FUEL AND EMISSION CONTROL SYSTEM
(FE DOHC) 30—21
FUEL AND EMISSION CONTROL SYSTEM
(DIESEL) 30—22
ENGINE ELECTRICAL SYSTEM 30—23
CLUTCH 30—25
MANUAL TRANSAXLE 30—26
AUTOMATIC TRANSAXLE
(ELECTRONICALLY CONTROLLED AND
4-SPEED) 30—27
AUTOMATIC TRANSAXLE (3-SPEED) 30—33
FRONT AND REAR AXLES 30—36
STEERING SYSTEM 30—36
BRAKING SYSTEM 30—37
WHEEL AND TIRE 30—38
SUSPENSION 30—38
BODY ELECTRICAL SYSTEM 30—39
STANDARD BOLT AND NUT
TIGHTENING TORQUE 30—40
76G30X-001

30 TECHNICAL DATA
0. MEASUREMENT
Item Engine model Coupe/MX-6 Sedan Hatchback

Overall length mm (in) 4,450 (175.2) 4,515 (177.8) 4,515 (177.8)
Overall width mm (in) 1,690 (66.5) 1,690 (66.5) 1,690 (66.5)
Overall height (14 inch/13 inch) mm (in) 1,360 (53.5)/1,345 (52.9) 1,410 (55 5)/1,395 (54.9) 1,375 (54.1)/1,360 (53 5)
Wheel base mm (in) 2,515 (99.0) 2,575 (101.4) 2,575 (101.4)
Tread (14 inch/13 inch)
mm (in)
Front 1,455 (57.3)/1,460 (57.5) 1,455 (57.3)/(1,460 (57.5) 1,455 (57.3)/1,460 (57.5) Tread (14 inch/13 inch)
mm (in)
Rear 1,465 (57.7)/1,455 (57.3) 1,465 (57.7)/1,455 (57.3) 1,465 (57 7)/1,455 (57 3)
1
A. ENGINE (SOHC)
12-valve
— Engine model Item FE 12-valve
~vpe
Gasoline, 4-cycle
Cylinder arrangement and number In-line, 4-cylinders
Type
of
combustion chamber Pentroof
Valve system OHC, belt-driven
Bore
x
Stroke
mm (in)
86.0
x
86.0 (3.39
x
3.39)
Total piston displacement
cc
(cu
in)
1,998 (121.9)
Compression ratio 9.5
: 1

Compression pressure
kPa (kg/cm2, psi)-rpm
Standard 1,422 (14.5, 206)—280
Compression pressure
kPa (kg/cm2, psi)-rpm
Minimum 996 (10.2, 144)—280 Compression pressure
kPa (kg/cm2, psi)-rpm Maximum difference
between cylinders 196 (2.0,
28)

Valve timing
IN
Open
BTDC 14°
Valve timing
IN Close ABDC 56° Valve timing
EX Open BBDC 69° Valve timing
EX Close ATDC 13°
Valve clearance
mm (in)
IN 0; Maintenance free Valve clearance
mm (in)
EX 0; Maintenance free

Cylinder head

Heiaht
mm (inl
91.95-92.05 (3.620-3.624)
Distortion
mm (inl
Maximum 0.15 (0.006)
Grinding limit
mm (in)
Maximum 0.20 (0.008)

Valve and valve auide

Valve head diameter
mm (in)
IN 32.4-32.6 (1.276—1.283) Valve head diameter
mm (in)
EX 33.9-34.1 (1.335-1.343)
Valve head thickness (margin)
mm (in)
IN 0.8-1.2 (0.031—0.0471 Valve head thickness (margin)
mm (in)
EX 1.3—1.7 (0.051-0.067)
Valve face angle IN 45° Valve face angle EX 45°
Valve length
mm (in)

IN Standard 115.81 (4.55941
Valve length
mm (in)

IN Minimum 115.31 (4.5398) Valve length
mm (in)
cv Standard 116.21 (4.5752)
Minimum 115.71 (4.55551
Valve stem diameter
mm (in)
IN 6.970-6.985 (0.2744-0.2750) Valve stem diameter
mm (in)
EX 6.965-6.980 (0.2742-0.27481
Guide inner diameter
mm (in)
IN 7.01-7.03 (0,2760-0.2768) Guide inner diameter
mm (in)
EX 7.01-7.03 (0.2760-0.27681
Valve stem
to
guide clearance
mm (in)

IN 0.025-0.060 (0.0010-0.0024)
Valve stem
to
guide clearance
mm (in)
EX 0.030-0.065 (0.0012—0.0026) Valve stem
to
guide clearance
mm (in)

Maximum 0.20 (0.00791
Guide projection (Height "A")
mm (in)
19.8-20.3 (0.780-0.799)

30—2