1987 MAZDA 626 engine

INSTALLATION 1B
Connector Location
Install each harness as shown in the figure.
76G01B-112
1. IG coil 10. Linear solenoid
2. Heat gauge unit 11. Solenoid valve (idle speed control)
3. Speed sensor 12. Throttle position sensor
4. P/S switch 13. Injection harness
5. Engine ground 14. Transmission harness
6. Water temperature sensor 15. Alternator
7. Water thermo switch 16. Oil pressure switch
8. Crank angle sensor 17. Starter
9. Oxygen sensor
1B-79

INSTALLATION 1B
76G01A-100
Air Cleaner Assembly
1. Install the air cleaner assembly.
Tightening torque:
16—27
N
m (1.6—2.8 m-kg, 12—20 ft-lb)
2. Connect the air flow sensor connector and air in-
take pipe.
Engine Oil
Add the specified amount and type of engine oil. (Re-
fer to Section 2A.)
Coolant
Close the drain plug, fill the radiator and reservoir tank
with the specified amount and type of coolant. (Re-
fer to Section 3A.)
Check Engine Condition
1. Check for leaks.
2. Perform engine adjustments if necessary.
3. Perform a road test.
4. Recheck the oil and coolant levels.
86U01X-204
1B-81

ENGINE
(DIESEL)
OUTLINE 1C— 2
STRUCTURAL VIEW 1C— 2
SPECIFICATIONS 1C— 3
TROUBLESHOOTING GUIDE 1C— 3
TUNE-UP PROCEDURE 1C— 5
ON-VEHICLE INSPECTION 1C—10
COMPRESSION 1C—10
ON-VEHICLE MAINTENANCE 1C—11
TIMING BELT 1C—11
CYLINDER HEAD 1C—16
VALVE SEAL 1C—24
REMOVAL 1C—31
DISASSEMBLY 1C—34
AUXILIARY PARTS 1C—34
TIMING BELT 1C—36
INJECTION PUMP 1C—39
CYLINDER HEAD 1C—40
CYLINDER BLOCK 1C—43
INSPECTION AND REPAIR 1C—47
ASSEMBLY 1C—62
CYLINDER BLOCK 1C—62
CYLINDER HEAD 1C—73
INJECTION PUMP 1C—78
TIMING BELT 1C—81
AUXILIARY PARTS 1C—87
INSTALLATION 1C—91
TRANSAXLE ASSEMBLY 1C—91
ENGINE INSTALLATION 1C—92 76G01C-001

TROUBLESHOOTING GUIDE 1 C
SPECIFICATIONS
———Engine model
Item ^—_______ RF-CX RF-N
Type Diesel, 4 cycle
Cylinder arrangement and number In line, 4 cylinders
Combustion chamber Swirl chamber
Valve system OHC, belt driven
Displacement cc (cu in) 1,998 (121.9)
Bore and stroke mm (in) 86.0 x 86.0 (3.39 x 3.39)
Compression ratio 21.1 : 1 22.7 : 1
Compression pressure
kPa (kg/cm2, psi)-rpm
Standard 2.943 (30, 427)-200 Compression pressure
kPa (kg/cm2, psi)-rpm Minimum 2.649 (27, 384)-200
Valve timing
IN Open BTDC 13° 13°
Valve timing
IN Close ABDC 15° 39° Valve timing
EX Open BBDC 60° 60° Valve timing
EX Close ATDC 8° 8°
Valve clearance mm (in)
Cold IN 0.25 (0.010)
Valve clearance mm (in)
Cold EX 0.35 (0.014) Valve clearance mm (in) Warm (for ref.)
IN 0.30 (0.012) Valve clearance mm (in) Warm (for ref.) EX 0.40 (0.016)
Idle speed (MTX in neutral) rpm 720
Injection timing ATDC 10 TDC 0°
Injection order 1_3_4_2
76G01C-002
TROUBLESHOOTING GUIDE
Problem Possible Cause Remedy Page
Difficult starting Malfunction of engine-related components
Burned valve Worn piston, piston ring, or cylinder Failed cylinder head gasket
Replace Replace or repair Replace
1C-48 1C—55,56 1C-16
Difficult starting
Malfunction of fuel system Refer to Section 4D
Difficult starting
Malfunction of Comprex supercharger Refer to Section 4D
Difficult starting
Malfunction of electrical system Refer to Section 5
Poor idling Malfunction of engine-related components Improper valve clearance Poor valve to valve seat contact Failed cylinder head gasket
Adjust Repair or replace Replace
1C-85 1C-50 1C—16
Poor idling
Malfunction of fuel system Refer to Section 4D
Poor idling
Malfunction of Comprex supercharger Refer to Section 4D
Excessive oil consumption
Oil working up Worn piston ring groove or sticking piston ring Worn piston or cylinder
Replace Replace or repair
1C-57 1C—55,56
Excessive oil consumption
Oil working down Worn valve seal Worn valve stem or guide
Replace Replace
1C-24 1C-48
Excessive oil consumption
Oil leakage Refer to Section 2B
76G01C-003
1C—3

1 C TROUBLESHOOTING GUIDE
Problem Possible Cause Remedy Page
Insufficient power Insufficient compression Improper valve clearance Compression leakage from valve seat Seized valve stem Weak or broken valve spring Failed cylinder head gasket Cracked or distorted cylinder head Sticking, damaged, or worn piston ring Cracked or worn piston
Adjust
Repair
Replace Replace Replace Replace Replace Replace
1C-85 1C-50 1C-48 1C-52 1C—16 1C-47 1C-57 1C-56
Malfunction of fuel system Refer to Section 4D
Malfunction of Comprex supercharger Refer to Section 4D
Others Slipping clutch Dragging brakes Wrong size tires
Refer to Section 6 Refer to Section 11 Refer to Section 12
Abnormal
combustion
Malfunction of engine-related components
Improper valve clearance
Sticking or burned valve
Weak or broken valve spring
Carbon accumulation in combustion chamber
Adjust
Replace
Replace Eliminate carbon
1C-85
1C-48
1C-52
Malfunction of fuel system Refer to Section 4D
Malfunction of Comprex supercharger Refer to Section 4D
Engine noise Crankshaft or bearing related parts Excessive main bearing oil clearance Main bearing seized or heat-damaged Excessive crankshaft end play Excessive connecting rod bearing oil clearance Connecting rod bearing seized or heat-damaged
Replace or repair Replace
Replace or repair Replace or repair Replace
1C-64 1C-64 1C-65 1C-66 1C-66
Piston related parts Worn cylinder Worn piston or piston pin Seized piston Damaged piston ring Bent connecting rod
Replace or repair Replace
Replace Replace Replace
1C-55 1C-58 1C-56 1C-57 1C-59
Valves or timing related parts Excessive valve clearance Broken valve spring Excessive valve guide clearance Malfunction of timing belt tensioner
Adjust Replace Replace Replace
1C-85 1C-52 1C-48 1C-61
Malfunction of cooling system Refer to Section 3B
Malfunction of fuel system Refer to Section 4D
Malfunction of Comprex supercharger Refer to Section 4D
Others Malfunction of water pump bearing Improper drive-belt tension Malfunction of alternator bearing Exhaust gas leakage
Replace Adjust Replace Repair
1C-7
1C—47
76G01C-004
1C—4

TUNE-UP PROCEDURE 1C
4BG01 B-006
4BG01B-007
76G01C-237
TUNE-UP PROCEDURE
Turn the engine according to the procedures
described below.
Battery
1. Check for corrosion on the terminals, or loose ca-
ble connections.
If necessary, clean the clamps and tighten firmly.
2. Check the electrolyte level.
If the level is too low, add distilled water to the "UP-
PER LEVEL" mark.
3. Check the specific gravity by using a hydrometer.
If the specific gravity reading is 1.200 or less,
recharge the battery, by referring to Section 5.
Air Cleaner Element
Visually check the air cleaner element for being ex-
cessively dirty, damaged or oil.
Clean or replace it 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.
Engine Oil
Check the engine oil level and condition with the oil
level gauge.
Add oil, or change it, if necessary.
4BG01B-009
1C—5

1C TUNE-UP PROCEDURE
Coolant Level
Check that the coolant level is near the radiator inlet
port, and that the level in the reserve tank is between
the FULL and LOW marks.
Add coolant up if the level is low.
Warning
Never remove the radiator cap when the en-
gine is hot.
Wrap a thick cloth around cap and carefully
remove the cap.
4BG01B-010
Water Draining
1. Drain the water from the sedimenter or fuel filter.
If it is difficult to drain the water from the drain plug,
loosen the air bleeding plug.
2. Bleed the air from the sedimenter or fuel filter. (Re-
fer to Section 4D)
76G01C-005
Valve Clearance
1. Remove the cylinder head cover.
2. Set the No. 1 cylinder to compression TDC.
Note
Turn the crankshaft so that the intake and ex-
haust cam lobes face upward.
4BG01B-016
3. Measure the valve clearance of No. 1 cylinder by
using a thickness gauge.
Valve clearance (cold engine)
0.20—0.30 mm (0.008—0.012 in)
0.30—0.40 mm (0.012—0.016 in)
If necessary, adjust the valve clearance referring to
the page 1C—85.
76G01C-006
1C-6

TUNE-UP PROCEDURE 1C
11. Turn the crankshaft clockwise to align the indica-
tor pin at ATDC 1° (RF-CX), ATDC 2° (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
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
If the idle speed is not within the specification, adjust
the idle speed referring to Section 4D.
76G01C-014
Exhaust Smoke
Increase and decrease the engine speed several
times and check that black smoke is not emitted.
If there is, refer to Section 4D for the appropriate
procedure.
76G01C-015
1C—9