MAZDA 626 1987 Workshop Manual

4C CONTROL SYSTEM
76G04C-207
76G04C-208
Replacement
1. Disconnect the knock sensor connector.
2. Lift the vehicle and remove the intake manifold
bracket.
3. Remove the knock sensor with the SST.
4. Install the knock sensor in the reverse order of
removal.
INTAKE AIR THERMO SENSOR (DYNAMIC
CHAMBER)
Inspection
1. Disconnect the intake air thermo sensor connector.
2. Connect an ohmmeter to the sensor terminals.
3. Check the resistance of the sensor.
Temperature Resistance (kQ)
20°C (68°F) 29.7—36.3
50°C (122°F) 8.4-10.2
85 °C (185°F) 2.5-3.1
4. Reconnect the sensor connector.
Replacement
1. Disconnect the intake air thermo sensor connector.
2. Remove the sensor.
3. Install the sensor.
Note
When installing the sensor, tighten to the
specified torque.
Specified torque:
6.9—8.8 N-m (0.7—0.9 m-kg, 72 in-lb)
76G04C-209
4C—110

4D
FUEL AND EMISSION
CONTROL SYSTEM
(DIESEL)
OUTLINE 4D— 2
SPECIFICATIONS 4D— 2
TROUBLESHOOTING GUIDE 4D— 3
ON-VEHICLE MAINTENANCE 4D— 4
AIR CLEANER ELEMENT 4D— 4
WATER DRAINING 4D— 4
AIR BLEEDING 4D— 4
INJECTION TIMING 4D— 5
IDLE SPEED 4D— 6
EXHAUST SMOKE 4D— 6
INTAKE AIR SYSTEM 4D— 7
STRUCTURAL VIEW 4D— 7
AIR DUCT AND AIR CLEANER 4D— 8
INTAKE MANIFOLD 4D— 9
SUPERCHARGING SYSTEM (RF-CX) 4D-10
TROUBLESHOOTING GUIDE 4D—10
ON-VEHICLE INSPECTION 4D—11
COMPREX SUPERCHARGER 4D—13
STARTING VALVE 4D—15
INTERCOOLER 4D—16
BOOST AIR TEMPERATURE SENSOR 4D—17
EXHAUST SYSTEM 4D—18
STRUCTURAL VIEW 4D—18
EXHAUST MANIFOLD 4D—19
EXHAUST PIPE AND MAIN SILENCER .... 4D—20
FUEL SYSTEM 4D—21
STRUCTURAL VIEW 4D—21
FUEL FILTER 4D—22
SEDIMENTER (GENERAL) 4D—22
WATER LEVEL SENSOR 4D—23
INJECTION PUMP 4D—24
INJECTION NOZZLE 4D—31
FUEL TANK 4D—34
76G04D-001

4D OUTLINE
OUTLINE
The Mazda 626 offers two diesel engines; a Comprex supercharged RF-CX engine, and a normally
aspirated RF-N engine.
SPECIFICATIONS
—Engine model
Item ———
ECE UK, GENERAL —Engine model
Item ——— RF-CX RF-N
Fuel tank Capacity liters (US gal, Imp gal) 60 (15.9, 13.2)
Fuel filter Type Cartridge, paper element
Sedimenter Type With detector
Injection pump
Type Bosch VE distributor
Injection pump
Manufacturer Diesel Kiki Co,, Ltd.
Injection pump
Direction of rotation Clockwise Injection pump
Drive method Timing belt
Injection pump
Plunger diameter mm (in) 9.0 (0.35) 8.0 (0.31)
Injection pump
Cam lift mm (in) 2.2 (0.087)
Injection nozzle Type Throttle Injection nozzle
Injection pressure kPa (kg/cm2, psi) 13,240 (135 , 1,920)
Injection timing ATDC
1
° TDC 0°
Idle speed rpm 720 _+f0
Fast idle speed (A/C ON) rpm 700-750
Cold start device Engine speed rpm 1.100 Cold start device
Advance degree 6°
Air cleaner Type Cartridge, paper element Air cleaner Type
Wet Dry
PCV system Type Open Closed
76G04D-002
4D—2

TROUBLESHOOTING GUIDE 4D
TROUBLESHOOTING GUIDE
Condition Condition Cause Remedy
Hard starting Fuel filter
Clogged Replace
Water or air in filter Repair
Fuel injection pump Faulty fuel cut solenoid Replace Incorrect injection timing Adjust
Air in pump Bleed
Faulty pump Replace
Fuel injection nozzle Seized needle valve Replace
Fuel dripping from nozzle Replace Incorrect valve opening pressure Adjust
Faulty glow plug Replace
Faulty cold start device Adjust or replace
Faulty supercharging system Refer to page 4D—10
Rough idle Fuel filter (Refer to "Hard starting") Fuel injection pump (Refer to "Hard starting")
Fuel injection nozzle
Seized needle valve Replace
Incorrect valve opening pressure Adjust
Improper mounting to nozzle holder Repair
Leakage of nozzle holder copper washer Replace
Fuel injection pipe Cranks Replace
Leaking from joint Repair
Improper idle speed adjustment Adjust
Engine knocking Incorrect injection timing Adjust
Low quality fuel Replace
Incorrect injection nozzle opening pressure Ajust
Seized injection nozzle needle valve Replace
Fuel dripping from injection nozzle Replace
Faulty supercharging system Refer to page 4D—10
High fuel Fuel injection pump consumption Incorrect injection timing Adjust consumption High idle speed Adjust, Inspect the dashpot
Fuel injection nozzle Incorrect valve opening pressure Repair
Fuel dripping from nozzle Replace
Leakage of nozzle holder copper washer Replace
Fuel leaking from connection Repair
Clogged fuel filter Replace
Clogged air cleaner Replace
Poor acceleration Fuel injection nozzle (Refer to "Hard starting")
Fuel injection pump (Refer to "Hard starting")
Fuel injection pipe (Refer to "Rough idle") Fuel filter (Refer to "Hard starting") Clogged air cleaner Clean or replace
Faulty supercharging system Refer to page 4D—10
Excessive exhaust Clogged air cleaner Clean or replace
smoke Improper injection timig Adjust
Faulty nozzle or nozzle holder Adjust or replace
Faulty supercharging system Refer to page 4D—10
76G04D-003
4D-3

4D ON-VEHICLE MAINTENANCE
ON-VEHICLE MAINTENANCE
76G04D-004
AIR CLEANER ELEMENT
Check the air cleaner element for excessive dirt, dam-
age, or oil. Replace if necessary.
Caution
(Wet type)
Do not clean the air cleaner element with com-
pressed air, replace if necessary.
(Dry type)
When cleaning the air cleaner element, blow
dust off from the inside first, then blow off the
outside.
(General)
1. Loosen the drain plug of the sedimenter and let
the water drain. If necessary loosen the air bleed-
ing plug.
2. Bleed air from the sedimenter.
AIR BLEEDING
From Fuel Tank to Fuel Filter
1. Loosen the air bleeding plug of the fuel filter.
2. Pump the priming pump until no air bubbles flow
from the air bleeding plug hole.
3. Depress the priming pump and tighten the air
bleeding plug.
Note
Open only the air bleeding plug of the filter.
From Fuel Filter to Injection Pump
Pump the priming pump until it becomes hard to
pump.
76G04D-007
WATER DRAINING
(ECE)
1. Loosen the drain plug of the fuel filter.
2. Pump the priming pump.
3. Bleed air from the fuel filter.
4D—4

ON-VEHICLE MAINTENANCE 4D
INJECTION TIMING
1. Disconnect the negative battery cable.
2. Release the CSD using the screw driver.
3. Remove the cover on the clutch housing.
4. Turn the flywheel and set the indicator at TDC.
5. Disconnect the injection pipes from the injection
pump.
76G04D-008
6. Remove the hydraulic head plug from the injec-
tion pump.
7. Mount the SST into the plug hole on the hydraulic
head so the tip of the dial gauge pointer touches
the plunger end of the pump and the dial gauge
indicates approx. 2.0 mm (0.08 in).
76.G04D-009
8. Turn the crankshaft slowly counterclockwise to
30—50° BTDC.
9. Make sure the dial indicator pointer no longer
moves by slightly turning the crankshaft.
10. Set the dial gauge scale to Zero at the pointer.
76G04D-010
11. Turn the crankshaft clockwise to align the indica-
tor pin at ATDC 1° (RF-CX), TDC 0° (RF-N).
12. Read the dial gauge.
Cam lift: 0.98—1.02 mm (0.038—0.040 in)
13. If not within the specification, adjust the injection
timing. (Refer to page 4D—24.)
76G04D-011
4D-5

4D ON-VEHICLE MAINTENANCE
IDLE SPEED
1. Warm up the engine to normal operating tem-
perature.
2. Be sure the A/C switch is OFF.
3. Connect a tachometer and check the engine
speed.
Idle speed: 720 :
20
rpm
76G04D-012
4. If necessary, adjust the idle by turning the idle ad-
justing screw.
76G04D-013
Fast Idle Speed (A/C equipped model)
1. Turn ON the A/C switch and blower motor switch.
2. Check the engine speed.
Fast idle speed: 725 ± 25 rpm
3. If necessary, turn the adjusting screw on the idle-
up actuator, and adjust the fast idle speed.
76G04D-014
EXHAUST SMOKE
Increase and decrease the engine speed several
times and check that there is no black smoke.
If
there
is, refer to the Troubleshooting Guide.
76G04D-015
4D—6

INTAKE AIR SYSTEM 4D
INTAKE AIR SYSTEM
STRUCTURAL VIEW
76G04D-016
1. Intake manifold 5. Starting valve
2. Intercooler 6. Air cleaner
3. Air funnel assembly 7. Air duct
4. Comprex supercharger
4D—7

INTAKE AIR SYSTEM 4D
AIR DUCT AND AIR CLEANER
Removal and Installation
1. Remove in the sequence shown in the figure.
2. Install in the reverse order of removal.
3. Check for air leakage.
1. Tire house cover
2. Air duct
3. Air hose
4. Air cleaner case
5. Air cleaner cover
6. Air cleaner
element
Inspection
Air cleaner
1. Inspect the silencer in the air cleaner cover for
damage.
2. Inspect the air cleaner element for excessive dirt,
damage, or oil. Replace if necessary.
Caution
(Wet type)
Do not clean the air cleaner element with com-
ressed air, replace it if necessary.
(Dry type)
When cleaning the air cleaner element, blow
dust off from the inside first, then blow off the
outside.
Air duct
Inspect the silencer in the air duct for damage. Re-
place if necessary.
76G04D-017
4D—8

INTAKE AIR SYSTEM 4D
INTAKE MANIFOLD
Removal and Installation
1. Remove in the sequence shown in the figure.
2. Install in the reverse order of removal.
3. Check for air/exhaust leakage.
76G04D-020
3. Vacuum hose (RF-CX)
4. Water thermo switch connector
5. Intake manifold
Inspection
1. Check the intake manifold for cracks and damage.
2. Inspect the flatness of the mounting surface using
a straight edge and a feeler gauge. Replace if
necessary.
Distortion: 0.05 mm (0.002 in) max.
19—26 N m (1.9—2.6 m-kg, 14—21 ft-lb)
8—11 N-m (80—110 cm-kg, 69—95 in-lb)
8—11 N-m (B0—110 cm-kg, 69—95 In-lb)
8—11 Nm (80—110 cm-kg, 69—95 In-lb)
19—26 N-m (1.9—2.6 m-kg, 14—19 ft-lb)
34—49 N-m (3.5—5.0 m-kg, 25—36 ft-lb)
8—11 N-m (80—110 cm-kg, 69—95 in-lb)
19—26 N-m (1.9—2.6 m-kg, 14—19 ft-lb) 22—26 N-m (2.2—2.7 m-kg, 16—20 ft-lb)
22—26 N m (2.2—2.7 m-kg, 16—20 ft-lb)
8—11 N-m (80—110 cm-kg, 69—95 in-lb)
1. Comprex supercharger
(Refer to page 4D—13.: RF-CX)
2. Exhaust manifold
(Refer to page 4D—19.: RF-CX)
76G04D-021
4D-9