1990 MAZDA 232 engine coolant

82 INSTALLATION
Steps after installation
1. If the engine oil was drained, refill with the specified amount and type of engine oil.
2. Fill the radiator with the specified amount and type of engine coolant.
3. Fill the transaxie with the specified amount and type of transaxle oil. (Refer to page J3-36.)
4. Connect the negative battery cable.
5. Start the engine and check the following:
(I) Engine oiI, transaxle oil, and engine coolant for leakage
(2) Ignition timing and idle speed
(3) Operation of emission control system
6. Perform a road test.
7. Recheck the engine oil and engine coolant levels.
93G032-747
-
BZ-34

E tNDEX
INDEX
-
- &ANT RESERVOlR
ENGiNE COOLANT
TOTAL CAPACITY
MTX: 5.0 liters (5.3 US qt, 4.4 Imp qt)
ATX: 6.0 liters (6.3 US qt. 5.3
tmp qt)
1. Fan motor
Inspection .._.....,._............._..........
page E-1 I
E-Z

E OUTLINE
OUTLINE
OUTttNE OF CONSTRUCTION
The cooling system in the 323 4WD model is basically the same as in the 323 2WD model.
Although there is no fundamental change from the BP DOHC of the 2WD model, the coolant circulation
path has been changed to direct coolant to the water-cooied turbocharger.
A two-stage thermostat is used in the BP DUHC turbocharged engine to stabilize the engine coolant tem-
peratu re.
The radiator and cooling fan specifications are different. The BP DOHC turbocharged engine of the 4WD
model uses a two-speed electric cooling fan.
93GOEX-704
COOLANT FLOW CHART (BP DOHC TURBO)
E-4

SPECIFICATlONS
-
km
Cootlng system
Coolant camacltv
EnginelTtansaxte
lrters [US Qt. Imo at)
8P SOHC ] 8P DOW Turbo
MTX ATX
I MTX
Water-cooled, forced crrculation
5.0 (5.3, 4.4)
I 6.0 t&3,5.3) -
1 Type
Water puma 1
I Water seal Centrifugal
Unified mechanical
seal
: Type I Wax,single stage”‘, Wax, two-stage*’ 1 Wax, two-stage
80.5-83.5 (177-182)“1
Opening temperature
“C (OF)
Main: 86.5-89.5 (188-l 93) *’ Main: 86.5-89.5 (lSS--193)
The:mosta! 1 Sub : 83.5-86.5 (182-188) Sub 83.G86.5 (182-188)
1 Full-open temperature OC
(OF) 95 (203)*‘, 100 (212)*’ i 100 (212)
L I
“...Except cold area, *2...Cotd area only
1 r 1 93GOEX-706 j Full-open lift mm (in) 8.5 (0.335) or more’l
Main: 8.0 (0.31).mln.‘2
Sub : 1.5 10.061 min * Main: 8.0 (0.31) min.
Sub : I.5 (0.06) mm.
Radiator 1 Type
Cap vaive opening-pressure ’
kPa (kglcm2, psi) Corrugated fin
74-l 03 (0.75-I .05, 11-l 5) j Tvm?
EIectnc I
Coohg fan f Outer drameter mm (in) 320 (12.6) 340 (13.4)
Blade
Number 4 5
Motor
/ Current A
6.6 * 1 Hi : 13.3 + 10% max.
Lo: 8.8 + 10% max. E-5

E OUTlANE
TWO-STAGE THERMOSTAT (BP DOHC TURBO)
MAIN VALVE
SINGLE-STAGE THERMOSTAT
(AMBIENT fEMP. -20% (4*f))
NTRANCE PORT TEMP
GINE EXIT PORT TEMP.
- 100 km/h
60 kndh
(63 mph) ~~~~~ (38 mph)
TWO-STAGE THERMOSTAT
A sub-valve is incorporated in the thermostat to stabilize the coolant temperature in the engine, to improve
cold weather performance, and to reduce heater output temperature fluctuations as noted in the diagram.
Operation
Stage 1
During cold weather operation, 83.5*C [182°F]-86.50C [t 88OF] only the sub-valve opens to control the
engine coolant temperature.
Stage 2
During normal operation, 86.5OC (1 88°F)-89.50C (I 93OF) the main valve opens to permit increased coul-
an: flow through the radiator.
E-6

E ELECTRIC COOLING FAN SYSTEM
ELECTRIC COOLING FAN SYSTEM (BP
DUHC TURBO)
SYSTEM ClRCUIT
r
WITH A/C
r-- _______ ------
I ADDITIONAL
1 FAN
I PRESSL
SWITCH
I WATER
THERMOSWfTCtl
ABOVE 87OC (207OF): ON
RADlATOjl THERMOSWITCH
ABOVE 105*C (221 “I=): ON
8 93GOEX-719
-
%
J--- QY- -THERMOME?ERsi-=i
--
--------L-
93GOEX-7 i 2
E-10 SYSTEM INSPECTION
1. Jump across the test fan (TFA) terminal and the ground
(GN D) terminal of the diagnosis connector.
2. Turn the ignition switch ON and verify that the fan operates.
If the fan does not operate, inspect the cooling fan system
components and wiring harness.
3. Remove the radiator cap and place a thermometer in the
radiator filler neck.
4. Start the engine.
5. Verify that the fan operates when the coolant temperature
reaches approx. 97*C (207°F).
If it does, check the water thermoswitch.
(Refer to page
E--i I.)

F2 CONTROL SYSTEM
KNOCK CONTROL SYSTEM [BP TURBO]
This svstem retards the ignition timina when enaine knocking occurs because of usage of low octane fuel, etc.
1NTAKE
MANIFO
KNOCK SENSOR
(INSTALLED BETWEEN No.2 AND
No.3 CYLINDER)
IGNITER
KNOCK iX?NTROL
UNIT
Operation
When the engine vibrates, the knock sensor generates a slight voltage signal that is the sent to the knock
control unit. The knock control unit determines whether the signal is a knocking signal. If it is a knocking
signal, the ignition spark is retarded according to the intensity of the knock to a maximum of 4O.
Inhibition of spark retardation
In order to improve drivability and fuel economy, the ECU inhibits the above spark retardation when the
‘engine load Ls light, the coolant temperature is below O°C (32OF), the engine is cranking during engine test
conditions.
Note
l The knock ~ensur and knock control unit cannot be inspected individually.
When a matfunction code number 05 is indicated, replace the knock controt unit or sensor
only after inspecting the related wiring and connectors.
F2-22

CONTROL SYSTEM F2
t OXYGEN SENSOR [BP TURBO]
I
CERAMlC HEATER
93GOF2-733
Because the temperature of the exhaust gas is inherently low in turbocharged engines, the BP Turbo model
uses a rapid heating ceramic heater to detect the air/fuel ratio,
PRESSURE REGULATOR CONTROL SYSTEM [BP TURBO]
PRESSURE
REGULATOR
I SOLENOID VALVE
(PRESSURE REGULATOR CONTROL)
FUEL
+ (FROM
DELIVERY PIPE1
II
FUEL INJ I
RELAY
(MAIN REU\Y)
I
II Ir
-__. _ - -’ VACUUM
CT0 DYNAMIC
Ill
CHAMBER)
BATTERY -
c
FUEL
(TO FUEL TANK)
nme*rn -.-a
To prevent percolation of the fuel during hot restart idle, vacuum to the pressure regulator k cut for 180
sec., and the fuel injection pressure is increased to slightly more than 284 kPa (2.90 kg/cm’, 41.2 psi).
Operating condition
l Coolant temperature: Above 90°C (194OF)
l Intake air temperature: Above 58OC (136OF)
g No-load condition
FZ-23