1987 MAZDA 626 lock

1 A DISASSEMBLY (CYLINDER BLOCK)
CYLINDER BLOCK—II
86U01X-073
6. Crankshaft
7. Pilot bearing (MTX)
8. Main bearing
9. Cylinder block
Disassembly Note
Connecting rod and cap
Before removing the connecting rod, clean the bear-
ing, connecting rod, and crankpin, and measure the
following points.
1. Connecting rod side clearance. (Refer to page
1A—67.)
2. Crankpin oil clearance.(Refer to page 1A—67.)
1. Connecting rod cap
2. Connecting rod bearing
3. Connecting rod and piston
4. Piston ring
5. Main bearing cap

1
A—46

DISASSEMBLY (CYLINDER BLOCK) 1 A
Main bearing cap
Before removing the main bearing caps, clean the
bearings, main journals, and caps, and measure the
following points.
1. Crankshaft end play. (Refer to page 1A—66.)
2. Main journal oil clearance. (Refer to page
1
A—65.)
76G01A-054
Pilot bearing (MTX)
Remove the pilot bearing from the crankshaft with the
SST.
86U01X-076
Piston and connecting rod
1. Before disassembling the piston and connecting
rod, check the oscillation torque as shown in the
figure.
If the large end does not drop by its own weight,
replace the piston or the piston pin.
79G01C-050
2. Remove the piston pin with the SST.
While removing the piston pin, check the pressure.
If it is lower than 5kN (500kg, 1,100 lb), replace
the piston pin or connecting rod.

76G01A-139

1A—47

INSPECTION AND REPAIR 1 A
76G01A-062
86U01X-092
76G01A-063
A vl^k
L^-X
B As^
Valve Spring
1. Inspect each valve spring for cracks or damage.
2. Check the free length and angle. Replace if
necessary.
Free length mm (in)
Standard Minimum
12-valve IN 49.5 (1.949) 49.0 (1.929) 12-valve EX 50.4 (1.984) 48.7 (1.917)
I FE.Middle Outer 51.2 (2.016) 50.6 (1.992)
8-valve East General Inner 45.7 (1.799) 43.7 (1.720) 8-valve
Others Outer 52.0 (2.047) 51.5 (2.028) 8-valve
Others Inner 44.0 (1.732) 43.3 (1.705)
Angle: 1.8 mm (0.071 in) max.
Camshaft
1. Set the front and rear journals on V-blocks.
Check the camshaft runout. Replace if necessary.
Runout: 0.03 mm (0.0012 in) max.
2. Check the cam for wear or damage. Replace if
necessary.
3. Check the cam lobe height at the two points as
shown in the figure.
Height mm (in)
Standard Minimum
12-valve IN 41.340 (1.6276) 41.14 (1.620) 12-valve EX 41.847 (1.6476) 41.65 (1.640)
8-valve IN 38.157 (1.5022) 37.96 (1.494) 8-valve EX 38.160 (1.5024) 37.96 (1.494)
4. Measure wear of the journals in X and Y directions
at the two points as shown in the figure.
Diameter mm (in)
12-valve 8-valve
No. 1,5 31.940-31.965 (1.2575-1.2585) 31.940-32.035 (1.2575-1.2612)
No. 2,3,4 31.910-31.935 (1.2563-1.2573) 31.910-32.065 (1.2563—1.2624)
Out-of-round: 0.05 mm (0.002 in) max.
76G01A-129

1
A—53

INSPECTION AND REPAIR 1 A
76G01A-065
76G01A-066
86U01X-100
(2) Measure the rocker arm shaft diameter.
Diameter:
18.959—18.980 mm (0.7464—0.7472 in)
...12 valve
15.966—15.984 mm (0.6286—0.6293 in)
... 8 valve
(3) Subtract the shaft diameter from the rocker arm
diameter.
Oil clearance mm (in)
Standard Maximum
12-valve 0.020-0.074
(0.0008-0.0029) 0.10 (0.0039)
8-valve 0.016-0.061 (0.0006-0.0024) 0.10 (0.0039)
Hydraulic Lash Adjuster (12-valve)
Check the HLA face for wear or damage. Replace
if necessary.
Caution
Do not remove the HLA unless necessary to
prevent damaging the O-ring.
Cylinder Block
1. Check the cylinder block. Repair or replace if
necessary.
(1) Leakage damage
(2) Cracks
(3) Scoring of wall
2. Measure the distortion of the top surface of the cyl-
inder block in the six directions as shown in the
figure.
Distortion: 0.15 mm (0.006 in) max.
3. If the distortion exceeds the maximum, repair by
grinding, or replace the cylinder block.
Grinding limit: 0.20 mm (0.008 in) max.

86U01X-117

1A—55

INSPECTION AND REPAIR 1 A
76G01A-070
76G01A-071
86U01X-109
Connecting Rod
1. Measure the connecting rod small end bore.
Diameter: 21.943—21.961 mm (0.8640—0.8646 in)
2. Check the interference between the small end bore
and piston pin.
Interference:
0.013—0.037 mm (0.0005—0.0015 in)
3. Check each connecting rod for bending or twist-
ing. Repair or replace if necessary.
Bend: 0.06 mm (0.0024 in) max.
Twist: 0.06 mm (0.0024 in) max.
Crankshaft
1. Check the journals and pins for damage, scoring,
or oil hole clogging.
2. Set the crankshaft on V-blocks.
3. Check the crankshaft runout at the center journal.
Replace if necessary.
Runout: 0.03 mm (0.0012 in) max.
4. Measure each journal diameter in X and Y direc-
tions at two points.
Main journal
Diameter:
59.937—59.955 mm (2.3597—2.3604 in)
Out-of-round: 0.05 mm (0.0020 in) max.
Crankpin journal
Diameter:
50.940—50.955 mm (2.0055—2.0061 in)
Out-of-round: 0.05 mm (0.0020 in) max.
76G01A-131
1A—59

1 A ASSEMBLY (CYLINDER BLOCK)
ASSEMBLY
1. Clean all parts before reinstallation.
2. Apply new engine oil to all sliding and rotating parts.
3. Replace plain bearings if they are peeling, burned, or otherwise damaged.
4. Tighten all bolts and nuts to the specified torques.
Caution
Do not reuse gaskets or oil seals.
CYLINDER BLOCK—I
Torque Specifications
69G01A-139
1A—62

ASSEMBLY (CYLINDER BLOCK) 1 A
Connecting Rod
1. Assemble the SST to the piston pin.
2. Apply engine oil to the piston pin.
86U01X-118
3. Set the piston on the SST with the F mark facing
upward.
4. Set the connecting rod in piston with the oil hole
in the large end opposite the F mark.
76G01A-135
5. Press the piston pin into the piston and connect-
ing rod until the SST contacts the block.
While inserting the piston pin, check the pressure
force. If it is less than specified, replace the piston
pin or the connecting rod.
Press force:
5—15 kN (500—1,500 kg, 1,100—3,300 lb)
Check the oscillation torque of the connecting rod.
(Refer to page 1A—47.)
76G01A-072
Piston Ring
1. Install the three-piece oil rings on the pistons.
(1) Apply engine oil to the oil ring spacer and rails.
(2) Install the oil ring spacer so that the opening
faces upward.
(3) Install the upper rail and lower rail.
Note
a) The upper rail and lower rail are the same.
b) Each rail can be installed with either face
upward.
69G01A-144
1A—63

1 A ASSEMBLY (CYLINDER BLOCK)
Spacer iang
Oil ring
spacer ends
Upper rail
Piston
Lower rail
69G01A-145
86U01X-121
Oil ring —
upper rail f .Top ring
Oil ring (
spacer r \30° \ . Pistion
^-^/ao0F pin
Oil ring
lower rail /Second ring
69G01A-147
2. Check that both rails are expanded by the spacer
tangs as shown in the figure by checking that both
rails turn smoothly in both directions.
3. Install the second ring to the piston first, then in-
stall the top ring. Use a piston ring expander.
Caution
The rings must be installed with the "R"
marks facing upward.
4. Apply a liberal amount of clean engine oil to the
second and top piston rings.
5. Position the opening of each ring as shown in the
figure.
Crankshaft
1. Before installing the crankshaft, inspect the main
bearing oil clearances as described.
Note
The bearing with thrust shoulders is the cen-
ter bearing in the cylinder block.

86U01X-136

1A—64