radiator MAZDA 626 1987 Owner's Guide

TROUBLESHOOTING GUIDE
3B

SPECIFICATIONS

Cooling system Water-cooled, forced circulation
Coolant capacity liters (US
qt,
Imp
qt)

With heater 9.5 (10.0, 8.4) Coolant capacity liters (US
qt,
Imp
qt)

Without heater 9.0 (9.5, 7.9)
Water pump Type Centrifugal, timing belt driven Water pump
Water seal Unified mechanical seal
Thermostat
Type Wax, two stage
Thermostat
Opening temperature °C(°F) Main Sub
Thermostat
Opening temperature °C(°F)
86.5-89.5 (188-193) 78.5—81.5 (173-179) Thermostat
Full-open temperature °C(°F) 100 (212) 100 (212)
Thermostat
Full-open lift
mm (in)
8.0 (0.31) min. 1.5 (0.06) min.
Radiator
Type Corrugated
fin

Radiator Cap valve opening pressure
kPa (kg/cm2,
psi)
74-103 (0.75-1.05, 11—15)
Cooling
fan

Type Electric
Cooling
fan

Capacity
W
120
Cooling
fan
Switching temprature orvopi OFF
- ON ^
91 (196) Cooling
fan

Number
of
blade 4
Cooling
fan

Outer diameter
mm
(in) 340 (13.4)

76G03B-003
TROUBLESHOOTING GUIDE
Problem Possible Cause Remedy Page
Overheating
Insufficient coolant Add 3B-
4

Coolant leakage Repair
—

Radiator fins clogged Clean 3B—
6

Radiator cap malfunction Replace 3B—
5

Cooling fan malfunction Repair 3B-11 Thermostat malfunction Replace 3B—
9

Water passage clogged Clean 3B—
4

Water pump malfunction ReDair
or
replace 3B—
7

Corrosion
Impurities
in
coolant Replace 3B-
4

76G03B-004
3B—3

3B COOLANT
86U03X-004
69G03A-006
COOLANT
INSPECTION
Coolant Level (Engine cold)
1. Check that the coolant level is near the radiator inlet
port.
2. Check that the coolant level in the coolant reser-
voir is between the FULL and Low marks.
Add coolant if necessary.
Warning
a) Never remove the radiator cap while the en-
gine is hot.
b)Wrap a thick cloth around the cap when
removing it.
Coolant Quality
1. Check that there is no build-up of rust or scales
around the radiator cap or radiator filler neck.
2. Check that coolant is free from oil.
3. Replace the coolant, if necessary.
Coolant Leakage
1. Connect a tester and SST to the radiator inlet port.
2. Apply 103 kPa (1.05 kg/cm2, 15 psi) pressure
to the system.
3. Check that the pressure is held.
If not, check for coolant leakage.
Warning
When removing either the radiator cap or the
tester, loosen it slowly until the pressure in
the radiator is released, and then remove it.
86U03X-005
REPLACEMENT
1. Remove the radiator cap and loosen the drain plug.
2. Drain the coolant into a suitable container.
Warning
a) Never open the radiator cap while the en-
gine is hot.
b)Wrap a thick cloth around the cap when
loosening.
c) Use caution when draining hot coolant.
86U03X-006
3B—4

RADIATOR CAP 3B
86U03X-028
86U03X-007
86U03X-008
3. Set the heater control switch to the maximum heat
position.
4. Flush the cooling system with water until all traces
of color are gone, then let the system drain com-
pletely.
5. Fill with the proper mixture and amount of ethy-
lene glycol-based coolant.
Caution
a) Do not use alcohol- or methanol-based
coolant.
b) Use only soft (demineralized) water in the
coolant mixture.
Anti-freeze solution mixture percentage

Protection Volume percentage Gravity
at

20°C (68°F) Protection Solution Water
Gravity
at

20°C (68°F)
Above —16°C (3°F) 35 65 1.054
Above -26°C (-15°F) 45 55 1.066
Above -40°C (-40°F) 55 45 1.078

6. Run the engine at idle with the radiator cap re-
moved. Let any air bleed from the system, and add
more coolant.
7. Install the radiator cap, and inspect all connections
for leakage.
RADIATOR CAP
INSPECTION
Radiator Cap Valve
1. Remove foreign material (such as water residue)
from between the radiator cap valve and the valve
seat.
2. Attach the radiator cap to a tester with the SST.
Apply pressure gradually to 74—103 kPa
(0.75—1.05 kg/cm2, 11—15 psi).
3. Wait about 10 seconds; then check that the pres-
sure has not decreased.
Negative Pressure Valve
1. Pull the negative-pressure valve to open it. Check
that it closes completely when released.
2. Check for damage on the contact surfaces, and
for cracked or deformed seal packing.
3. Replace the radiator cap if necessary.
86U03X-009
3B-5

3B RADIATOR
Note
a) Position the hose clamp in the original location on the hose.
b) Squeeze the clamp lightly with large pliers to ensure a good fit. 86U03X-010
RADIATOR
REMOVAL AND INSTALLATION
1. Drain the engine coolant.
2. Remove in the sequence shown in the figure.
3. Install in the reverse order of removal.
1. Coolant reservoir hose
2. Fast idle solenoid
3. Coolant level sensor connector
4. Cooling fan connector
76G03B-005
5. Upper and lower radiator hose
6. Cooling fan and radiator assembly
7. Cooling fan
INSPECTION
Check the following points. Repair or replace if
necessary.
1. Cracks, damage, or water leakage
2. Bent fins (Repair with a screwdriver)
3. Distorted or bent radiator inlet
86U03X-012
3B-6

THERMOSTAT 3B
THERMOSTAT
REMOVAL
1. Drain the engine coolant.
2. Disconnect the upper radiator hose, and water
thermo switch connector.
3. Remove the thermostat cover.
4. Remove the thermostat.
76G03B-010
76G03B-011
Sub valve Main valve
I
INSPECTION
Check the thermostat. Replace if necessary.
1. Visually check that the valve is airtight.
2. Place the thermostat and a thermometer in water.
3. Gradually heat the water and check the following:
Valve opening temperature
Sub valve : 78.5—81.5°C (173—179°F)
Main valve : 86.5—89.5°C (188—193°F)
Full open lift
Sub valve : 1.5 mm (0.06 in) min. at
100°C (212°F)
Main valve : 8 mm (0.31 in) min. at
100°C (212°F)
Valve closing temperature
Sub valve : 75°C (167°F)
Main valve : 83°C
(181
°F)
69G03B-012
76G03B-012
INSTALLATION
1. Install the thermostat into the thermostat case with
jiggle pin at the top.
2. Install a new gasket with the seal print side facing
the thermostat case.
3. Install the thermostat cover.
Tightening torque:
7—10 N-m (70—100 cm-kg, 61—87 in-lb)
4. Install the upper radiator hose and water thermo
switch connector.
5. Replenish the coolant.
6. Start the engine and check for leaks.
3B-9

Diaphragm

Intake air temperature
Water thermo switches*2 Vacuum switch*2 E/L switches*2 Inhibitor switch*2 Ignition coil
Fuel pump
Water thermo
switch*2
(on radiator)
*1 MTX
*2 Except F6
*3 F6
*4 Except F8 ATX and F6
*5 F6 MTX
*6 Except F8 ATX and F6 ATX
*7 F8 MTX and FE

4A PTC HEATER SYSTEM
PTC HEATER SYSTEM
[FE
and
F8 engine (except Middle
East)]
76G04A-071
The PTC heater system consists of the PTC heater, relay, and water thermo switch. The system is
designed to prevent carburetor icing when the engine operating temperature is low t assure optimum
driveability.
TROUBLESHOOTING
Note
Make the system inspection first. If no problem is found, continue with the next inspec-
tion of the Troubleshooting Guide. (Refer to pages 4A—19, —20, or—22)
FE 8Valve—Unleaded Fuel
Possible cause System
inspection
Water thermo switch (intake manifold)
PTC heater
Water
thermo
switch
(Radiator)
PTC heater
relay
Page 4A—43 4A—41 4A—43 4A—95 4A—44
Checking order 1 2 3 4 5
Except FE 8Valve—Unleaded Fuel
Possible cause System inspection
Water thermo switch (Radiator)
PTC heater PTC heater
relay
Page 4A—43 4A—95 4A—43 4A—44
Checking order 1 2 3 4
76G04A-072
4A-42

PTC HEATER SYSTEM 4A
System Inspection
Except FE 8Valve—Unleaded Fuel
1. Connect a voltmeter to the PTC heater connector.
2. Start the engine and measure the voltage.
Specification
Radiator coolant
temperature Below 17°C (63°F) Above
17°C (63°F)
Voltage Approx. 12V ov
76G04A-073
FE 8Valve—Unleaded Fuel
1. Start the engine.
2. Connect a voltmeter to the PTC heater connector
terminals and measure the voltage.
Voltage
Engine coolant
temperature
Below 67°C (152°F)
Above 67°C (152°F)
Radiator coolant temperature Below 17°C (63°F) Above 17°C (63°F) —
Terminal BrB Approx.
12V
OV OV Terminal BrW
Approx.
12V Approx. 12V OV
76G04A-074
PTC Heater
Except FE 8Valve—Unleaded Fuel
1. Disconnect the PTC heater connector.
2. Check for continuity of the heater with an
ohmmeter.
76G04A-075
FE 8Valve—Unleaded Fuel
1. Disconnect the PTC heater connector.
2. Check for continuity between terminal wire (BrW)
and a ground.
3. Check for continuity between terminal wire (BrB)
and (B).
76G04A-076
4A—43

DECELERATION CONTROL SYSTEM 4 A
MAIN AIR BLEED CONTROL SYSTEM
FE and F8 (ECE, Hong Kong, Singapore, and General)
Primary
Air/Fuel mixture—Lean Air/Fuel mixture—Rich
76G04A-093
This system prevents the additional air from being fed to the primary air bleed circuit and causes the
air/fuel mixture to become rich, improving acceleration.
Troubleshooting
Possible cause System inspection Solenoid valve Vacuum switch Water thermo
switch (Radiator)
Page 4A—52 4A—52 4A—94 4A—95
Checking order 1 2 3 4
Note
Make the system inspection first. If no problem is found, continue with the next inspec-
tion of the Troubleshooting. (Refer to pages 4A—46 or —47.)
4A—51

4 A DECELERATION CONTROL SYSTEM
Solenoid valve (for main air bleed control system)
76G04A-094
76G04A-095
76G04A-191
System Inspection
1. Disconnect the vacuum switch connector.
2. Make sure that radiator coolant temperature is be-
low 17°C (63°F).
3. Disconnect the upper vacuum hose from the sole-
noid valve.
4. Place a finger over the solenoid valve open port
and check that vacuum is not felt when engine is
running.
5. Warming up the engine.
6. Place a finger over the same open port of the sole-
noid valve and check that weak vacuum is felt.
7. Reconnect the vacuum switch connector.
8. Check that weak vacuum is felt at the open port
of the solenoid valve at idle.
9. Accelerate the engine rapidly and check that vacu-
um is not felt.
Solenoid Valve (A/C)
1. Disconnect vacuum hose A (White) from the car-
buretor.
2. Disconnect vacuum hose B from the solenoid
valve.
3. Disconnect the solenoid valve connector.
4. Blow air through the valve from hose A and check
that it comes out of port C.
5. Apply 12V and ground to the solenoid valve with
jumper wires.
6. Blow air through the valve from hose A and check
that air not come out.
7. Replace if necessary.
76G04A-192
4A—52