1987 MAZDA 626 belt

TROUBLESHOOTING GUIDE 1 B
Problem Possible Cause Remedy Page
Insufficient power Insufficient compression Malfunction of HLA 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
Replace Repair
Replace
Replace Replace Replace Replace Replace
1B—60 1B—37 1B—35 1B—38 1B-16 1B—34 1B—43 1B—43
Malfunction of fuel system Refer to Section 4C
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 Malfunction of HLA Sticking or burned valve
Weak or broken valve spring Carbon accumulation in combustion chamber
Replace Replace Replace
Eliminate carbon
1B-60
1B-35
1B—38
Malfunction of fuel system Refer to Section 4C
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
1B-51 1B—51 1B—52 1B—53 1B—53
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
1B—41 1B-44 1B—43 1B—43 1B-44
Valves or timing related parts Malfunction of HLA* Broken valve spring Excessive valve guide clearance Malfunction of timing belt tensioner
Replace Replace Replace Replace
1B-60 1B—38 1B—35 1B—47
Malfunction of cooling system Refer to Section 3A
Malfunction of fuel system Refer to Section 4C
Others Malfunction of water pump bearing Improper drive belt tension Malfunction of alternator bearing Exhaust gas leakage
Replace Adjust Replace Repair
1B— 6
1B—34
* Tappet noise may occur if the engine is not operated for an extended period of time. The noise should stop after the engine has reached normal operating temperature. 76G01B-004
1B—4

1B TUNE-UP PROCEDURE 1 B
86U01X-008
Coolant Level (Cold engine)
1. Check that the coolant level is near the radiator inlet
port.
2. Check that the level in the coolant reservoir is be-
tween 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 and care-
fully remove it.
Drive Belt
1. Check that the drive belt is positioned in the pul-
ley groove.
2. Check the drive belt for wear, cracks, or fraying.
Replace if necessary.
3. Check the drive belt tension by using the tension
gauge.
Standard belt tension N (kg, lb)
76G01B-006

Belt New Used
Alternator 589-785 (60-80, 132-176) 491-687 (50-70, 110-154)
P/S 687-883 (70-90,154-198) 589-785 (60-80.132-176)
A/C 687-883 (70-90,154-198) 589-785 (60-80,132-176)

76G01B-007
Adjusting bolt
76G01B-008
4. Check the drive belt deflection by applying moder-
ate pressure (98 N, 10 kg, 22 lb) midway between
the pulleys.
(1) Alternator belt deflection
New : 6—8 mm (0.24—0.31 in)
Used: 7—9 mm (0.27—0.35 in)
If necessary, loosen the alternator mounting
bolts and adjust the belt deflection by turning
the adjusting bolt.
Tightening torque
®: 31—46 Nm (3.2—4.7 m-kg, 23—34 ft-lb)
(§): 37—52 Nm (3.8—5.3 m-kg, 27—38 ft-lb)
(2) P/S belt deflection
New : 8—10 mm (0.31—0.39 in)
Used: 9—11 mm (0.35—0.43 in)
If necessary, loosen the idler pulley lock bolt
and adjust the belt deflection by turning the ad-
justing bolt.
Tightening torque of lock bolt:
37—52 N-m (3.8—5.3 m-kg, 27—38 ft-lb)
1B—6

TUNE-UP PROCEDURE 1 B
76G01A-009
76G01A-010
Wear and adhesion of carbon
Burnt
Damage and
deterioration
Damage
76G01B-118
| © © AU
(3) A/C belt deflection
New : 7—9 mm (0.27—0.35 in)
Used: 8—10 mm (0.31—0.39 in)
If necessary, loosen the A/C mounting bolts
and adjust the belt deflection by turning the ad-
justing bolt.
Tightening torque
(A): 37—52
N
m (3.8—5.3 m-kg, 27—38 ft-lb)
(§): 37—52 Nm (3.8—5.3 m-kg, 27—38 ft-lb)
(4) P/S and A/C belt deflection
New : 7—9 mm (0.27—0.35 in)
Used: 8—10 mm (0.31—0.39 in)
If necessary, adjust the belt deflection using the
same procedure as used for the A/C belt
deflection.
Spark Plug
Check the following points. Clean or replace if
necessary.
1. Damaged insulation
2. Worn electrodes
3. Carbon deposits
4. Damaged gasket
5. Burnt spark insulator
6. Plug gap
Plug gap:
0.7—0.8 mm (0.028—0.031 in)
Distributor Cap
Check the following points. Replace if necessary.
1. Cracks or carbon deposits
2. Burnt or corroded terminals
3. Worn distributor center contact

76G01B-008

1B—7

TUNE-UP PROCEDURE 1 B
High-Tension Lead
Check the following points. Clean or replace if
necessary.
1. Damaged lead
2. Carbon deposits
86U01X-014
i^rrr ' /
49 0187 280
76G01B-011
76G01B-012
Hydraulic Lash Adjuster (HLA)
Note
Tappet noise may occur if the engine is not
operated for an extended period of time. The
noise should stop after the engine has
reached normal operating temperature.
1. Check for tappet noise. If noise exists, check the
following points.
(1) Engine oil condition and level
(2) Engine oil pressure (Refer to Section 2A)
2. If the noise does not stop, check for movement of
each HLA by pushing it during disassembly.
3. If the HLA moves, replace the HLA. (Refer to page
1B—60.)
Ignition Timing
1. Warm up the engine and run it at idle.
2. Turn all electric loads OFF.
3. Connect a timing light tester.
4. Disconnect the vacuum hose from the vacuum
control, and plug the hose.
5. Check that the ignition timing mark (yellow) on the
crankshaft pulley and the timing mark on the tim-
ing belt cover are aligned.
Ignition timing: 12° ± 1° BTDC
(at idle speed)

76G01B-008

1B—8

ON-VEHICLE MAINTENANCE (TIMING BELT) 1 B
ON-VEHICLE MAINTENANCE
TIMING BELT
Removal
1. Disconnect the negative battery cable.
2. Remove in the sequence shown in the figure referring to the removal note for specially marked parts.
76G01A-108
76G01B-020
1. Center cover
2. High-tension lead and spark plug
3. Engine side cover
4. Drive belt
5. Crankshaft pulley
6. Engine mount bracket
7. Upper timing belt cover
8. Lower timing belt cover
9. Baffle plate
10. Timing belt tensioner
11. Timing belt tensioner spring
12. Timing belt
1B—11

ON-VEHICLE MAINTENANCE (TIMING BELT) 1 B
76G01B-021
Removal note
Timing belt tensioner
1. Turn the crankshaft to align the mating marks of
the camshaft pulleys.
Note
For intake side camshaft pulley, align "I"
mark.
For exhaust side camshaft pulley, align "E"
mark.
2. Remove the tensioner.
Timing belt
Mark the timing belt rotation for proper reinstallation
if it is reused.
Caution
Be careful not to allow oil, grease, or water
on the belt.
86U01X-024
Inspection
Inspect the following parts. (Refer to page 1B—46,
47.)
1. Timing belt
2. Timing belt tensioner and spring
3. Timing belt idler pulley
4. Timing belt pulley
5. Camshaft pulley
76G01B-022
1B—12

1 B ON-VEHICLE MAINTENANCE (TIMING BELT)
Installation
Install in the reverse order of removal referring to the installation note.
Torque Specifications 76G01A-109
8—12 N m (80—120 cm-kg, 69—104 In-lb)
Installation note
Timing belt
1. Check that the mark on the timing belt pulley is
aligned with the mating mark.
2. Check that the mating mark of the camshaft pul-
leys are aligned with the seal plate mating marks.
Note
For intake side camshaft pulley, align "I"
mark.
For exhaust side camshaft pulley, align "E"
mark.

76G01B-026

1B—13

1 B ON-VEHICLE MAINTENANCE (TIMING BELT)
3. Install the timing belt tensioner and spring. Tem-
porarily secure it with the spring fully extended.
Caution
Do not damage the pulleys when securing the
tensioner pulley.
76G01B-024
4. Install the timing belt so that there is no looseness
at the tension side, and at the two camshaft pulleys.
Caution
a) If the timing belt is being reused, it must be
reinstalled to rotate in the original direction.
b) Check that there is no oil, grease, or dirt on
the timing belt.
76G01B-025
5. Loosen the tensioner lock bolt.
6. Turn the crankshaft twice in the direction of rota-
tion, and align the mating marks.
7. Check that the timing marks are correctly aligned.
If not aligned, remove the timing belt tensioner and
timing belt, and repeat steps 1—6.
69G01B-027
8. Turn the crankshaft to align the "S" mark of the
right side camshaft pulley with seal plate mating
mark.
Tighten the timing belt tensioner lock bolt.
Tightening torque:
37—52 Nm (3.8—5.3 m-kg, 27—38 ft-lb)
76G01B-026
1B—14