engine MAZDA 626 1987 Workshop Manual
Page 343 of 1865
3A TROUBLESHOOTING GUIDE i 
SPECIFICATIONS 
^Engine model 
Item ^__ 
FE-DOHC 
FE 8-valve, 
F8, F6...except 
Middle East 
.General 
FE 12-valve 
FE 8-valve F8, F6...only Middle East General 
Cooling system Water cooled, forced circulation 
Coolant capacity liters (US qt, Imp qt) 
With heater 7.5 (7.9, 6.6) Coolant capacity liters (US qt, Imp qt) Without heater 7.0 (7.4, 6.2) 
Water pump Type Centrifugal, timing belt driven Water pump 
Water seal Unified seal 
Thermostat 
Type Wax, 2-stage Wax 
Thermostat 
Opening temperature °C(°F) Sub
 .
 83.5-86.5 (182-188) Main: 86.5-89.5 (188-193) 86.5-89.5 (188-193) 80.5-83.5 (177-182) Thermostat 
Full-open temperature °C(°F) 100 (212) 95 (203) 
Thermostat 
Full-open lift
 mm
 (in) Sub: 1.5 (0.06) min. 
Main: 8.0 (0.31) min. 8.5 (0.33) min. 
Radiator 
Type Corrugated 
Radiator Cap valve opening pressure 
kPa (kg/cm2, psi) 74-103 (0.75-1.05, 11-15) 
Cooling
 fan 
Capacity
 W 
MTX 80 
Cooling
 fan 
Capacity
 W 
ATX 120 
Cooling
 fan 
Number
 of
 blade 4 Cooling
 fan 
Outer diameter
 of
 blade
 mm
 (in) MTX 320 (12.6) 
Cooling
 fan 
Outer diameter
 of
 blade
 mm
 (in) 
ATX 340 (13.4) 
76G03A-003 
TROUBLESHOOTING GUIDE 
Problem Possible Cause Remedy Page 
Overheating 
Insufficient coolant Add 3A—
 5 
Coolant leakage Repair 
— 
Radiator fins clogged Clean 3A—
 7 
Radiator cap malfunction Replace 3A-
 6 
Cooling fan malfunction Repair 3A-12 Thermostat malfunction Replace 3 A-11 
Water passage clogged Clean 3A—
 5 
Water
 DumD
 malfunction ReDair
 or
 replace 3A-
 8 
Corrosion 
Impurities
 in
 coolant Replace 3A-
 5 
76G03A-004 
3A—4  
Page 344 of 1865
COOLANT 3A 
76G03A-016 
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 
3A-5  
Page 345 of 1865
3A RADIATOR CAP 
J I 
V
 J* J Q lanana 
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 
3A—6  
Page 346 of 1865
RADIATOR 3A 
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. 
76G03A-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. 
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 
1. Coolant reservoir hose 
2. ATF hose (ATX) 
3. Water thermo switch connector 
4. Cooling fan connector 
86U03X-012 
3A-7  
Page 347 of 1865
3A WATER PUMP 
WATER PUMP 
REMOVAL 
1. Disconnect the negative battery cable. 
2. Turn the crankshaft so that the No. 1 cylinder is at TDC of compression. 
3. Drain the engine coolant. 
4. Remove in the sequence shown in the figure. 
1. Timing belt (Refer to Section 1B) 4. Idler pulley 
2. Camshaft pulley (Refer to Section 1B) 5. Water pump 
3. Seal plate 6. O-ring 
3A—8  
Page 350 of 1865
THERMOSTAT 3A 
69G03B-010 
76G03A-008 
76G03A-009 
THERMOSTAT 
REMOVAL 
1. Drain the engine coolant. 
2. Remove the thermostat cover. 
3. Remove the thermostat. 
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: 
\ Model 
Item  
FEDOHC 
FE 8-valve F8,F6...except 
Middle
 East General FE 12-valve 
FE 8-valve, F8,F6...only Middle East General 
Initial opening 
tem-
perature 
Sub
 valve 83.5—86.5°C (182—188°F) Main valve 86.5—89.5°C (188—193°F) 
86.5—89.5°C 
(188—193°F) 
80.5—83.5°C (177—182°F) 
Full-open 
temperature 100°C (212°F) 95°C (203°F) 
Full-open 
lift 
Sub
 valve 
1.5
 mm 
(0.06 in) min. 
Main valve 
8.0
 mm 
(0.31 in) min. 
8.5
 mm
 (0.33
 in)min. 
INSTALLATION 
1. Install the thermostat into the cylinder head with 
jiggle pin at the top. 
2. Install a new gasket with the seal print side facing 
the cylinder head. 
3. Install the thermostat cover. 
Tightening torque: 
19—30
 N
 m (1.9—3.1 m-kg, 14—22 ft-lb) 
4. Replenish the coolant. 
5. Start the engine and check for leaks. 
86U03X-018 
3 A-11  
Page 357 of 1865
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  
Page 358 of 1865
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  
Page 359 of 1865
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  
Page 360 of 1865
WATER PUMP 3B 
WATER PUMP 
REMOVAL 
1. Disconnect the negative battery cable. 
2. Turn the crankshaft so that the No. 1 cylinder is at TDC of compression. 
3. Drain the engine coolant. 
4. Remove in the sequence shown in the figure. 69G03A-025 
31—46 N m (3.2—4.7 m-kg, 23—34 ft-lb) 
19—26 N-m (1.9—2.6 m-kg, 14—19 ft-lb) 
(?) 8—11 N-m (80—110 cm-kg, 69—95 In-lb) 
37—52 N-m (3.8—5.3 m-kg, 27—38 ft 
55—65 N-m (5.6—6.6 m-kg, 41-48 ft-lb) 
(80—110 cm-kg, 69—95 In-lb) 
59—69 N-m (6.0—7.0 m-kg, 43—51 ft-lb) 
76G03B-006 
1. Timing belt (Refer to page 1C—11) 
2. Camshaft pulley (Refer to page 1C—36) 
3. Injection pump pulley (Refer to page 
1C—36) 
4. Seal plate 
Note 
Do not disassemble the water pump body, if a problem is found replace it as a unit. 
5. Alternator 
6. Water pipe 
7. Water hose 
8. Water pump body 
9. Water pump inlet 
3B-7