1987 MAZDA 626 lock

1 C DISASSEMBLY (CYLINDER BLOCK)
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.
76G01C-095
2. Remove the snap rings from the piston.
3. Remove the piston pin with the SST.
76G01C-249
76G01C-096
Main bearing cap
During disassembly, clean the bearings, main jour-
nals, and caps, and measure the following:
1. Crankshaft end play. (Refer to page 1C—65.)
2. Main journal oil clearance. (Refer to page 1C—64.)
Pilot bearing
Remove the pilot bearing from the crankshaft with the
SST.
76G01C-097
1C—46

INSPECTION AND REPAIR 1C
(2). Measure the inner diameter of the tappet hole
in the cylinder head.
Hole diameter:
34.99—35.01 mm (1.3776—1.3787 in)
2. Calculate the difference (clearance) between the
tappet diameter and hole inner diameter.
If the clearance exceeds the specification , replace
the tappet or the cylinder head.
Clearance: 0.10 mm (0.004 in) max.
76G01C-120
76G01C-121
76G01C-122
Camshaft
1. Set the front and rear journals on V-blocks.
Check the camshaft runout. Replace if necessary.
Runout: 0.10 mm (0.004 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 Mimimum
RF-CX IN 42.521 (1.6741) 42.11 (1.658) RF-CX EX 45.300 (1.7835) 44.90 (1.768)
RF-N IN 44.306 (1.7443) 43.90 (1.728) RF-N EX 45.300 (1.7835) 44.90 (1.768)
4. Measure wear of the journals in X and Y directions
at the two points as shown in the figure.
Diameter:
31.959—31.975 mm (1.2582—1.2589 in)
Out-of-round: 0.05 mm (0.002 in) max.

76G01C-144

1C-53

INSPECTION AND REPAIR 1C
76G01C-127
76G01C-128
Feeler gauge
76G01C-129
6. Measure the camshaft end play. If it exceeds the
maximum, replace the camshaft and/or the cylin-
der head.
End play:
0.02—0.15 mm (0.0008—0.0059 in)
Maximum: 0.20 mm (0.008 in)
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: 0.10 mm (0.004 in) max.
3. If the distortion exceeds the maximum, replace the
cylinder block.
Caution
Do not grind the surface of the cylinder block.
4. Measure the cylinder bore in directions X and Y
at three levels in each cylinder as shown.
Cylinder bore mm (in)
Size Bore
Standard 86.000-86.022 (3.3858—3.3867)
0.25 (0.010) oversize 86.250—86.272 (3.3957—3.3965)
0.50 (0.020) oversize 86.500-86.522 (3.4055—3.4064)

76G01C-144

1C-55

INSPECTION AND REPAIR 1C
4. Check each connecting rod for bending or twist-
ing. Repair or replace if necessary.
Bend:
0.080 mm (0.0031 in) max.
/50 mm (1.969 in)
Twist:
0.080 mm (0.0031 in) max.
/50 mm (1.969 in)
76G01C-141
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: 0.05 mm (0.002 in) max.
76G01C-142
76G01C-143
Crankpin
Main journal
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)
Minimum: 59.89 mm (2.358 in)
Out-of-round: 0.05 mm (0.002 in) max.
Crankpin journal
Diameter:
50.940—50.955 mm (2.0055—2.0061 in)
Minimum: 50.89 mm (2.004 in)
Out-of-round: 0.05 mm (0.002 in) max.
5. If the diameter is less than the minimum, grind the
journals to match undersize bearings.
Undersize bearing: 0.25 mm (0.010 in),
0.50 mm (0.020 in), 0.75 mm (0.030)
Main journal diameter undersize mm (in)
Bearing size Journal diameter
0.25 undersize 59.687-59.705 (2.3499—2.3506)
0.50 undersize 59.437-59.455 (2.3400-2.3407)
0.75 undersize 59.187-59.205 (2.3302-2.3309)
76G01C-144
1C-59

1 C 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
1C—62

ASSEMBLY (CYLINDER BLOCK) 1 C
Cavity
"F" mark
o
/-Matching mark
76G01C-147
76G01C-252
Top ring and — 90° •v. Second ring expanders. •v. Second ring
457//
iW
\ /
-J^/ \Oil ring
4BG01B-153
RF-CX RF-N
—ll Br1 &Top
GO [IP 2nd
fa? r® oil
Piston ring
Connecting Rod
1. Align the piston cavity and matching mark in the
large end of the connecting rod.
2. Apply engine oil to the circumference of each pis-
ton pin and to the small end of each connecting
rod.
3. Insert a snap ring into one of the piston pin holes
in the piston.
4. Install the piston pin using the SST.
5. Connect the piston and connecting rod by the pis-
ton pin, and lock the snap ring.
Note
Heat the piston to 50—70°C (120—170°F) for
installation.
Piston Ring
1. Apply a liberal coat of engine oil to the piston rings.
2. Install the oil ring expander and the oil ring.
3. Install the second ring.
4. Install the top ring.
5. Align the piston ring end gaps, as shown in the
figure.
Caution
The rings must be mounted so the "R" or "N"
marks face upward.
76G01C-148
1C—63

1 C ASSEMBLY (CYLINDER BLOCK)
Crankshaft
1. Before installing the crankshaft, inspect the main
bearing oil clearances as described.
Oil clearance inspection
(1) Remove any foreign material and oil from the
journal and bearing.
(2) Install the upper main bearings in the cylinder
block.
(3) Set the crankshaft into the cylinder block.
76G01C-149
(4) Position the plasti-gauge on top of the journals
in the axial direction.
76G01C-150
(5) Install the main bearing caps along with the
lower main bearings according to the cap num-
ber and ^ mark.
(6) Tighten the caps in two or three steps in the
order in the figure.
Tightening torque:
82—88
N
m (8.4—9.0 m-kg, 61—65 ft-lb)
Caution
Do not rotate the crankshaft when measuring
the oil clearances.
(7) Remove the main bearing caps, and measure
the plasti-gauge at each journal at the widest
point for the smallest clearance, and at the nar-
rowest point for the largest clearance.
If the oil clearance exceeds specification, grind
the crankshaft and use undersize main bear-
ings. (Refer to page 1C—59.)
Oil clearance:
0.031—0.050 mm (0.0012—0.0020 in)
Maximum: 0.08 mm (0.0031 in)
76G01C-152
1C-64

ASSEMBLY (CYLINDER BLOCK) 1 C
Cylinder block side Crankshaft side
Lower side
4BG01B-159
2. Apply engine oil to the main bearings and main
journals.
3. Install the crankshaft and bearings.
4. Install the main bearing cap according to the cap
number and mark, and tighten it evenly in or-
der shown in the figure.
5. Check that the crankshaft turns easily.
76G01C-153
6. Inspect the crankshaft end play.
End play:
0.040—0.282 mm (0.0016—0.0111 in)
Maximum: 0.30 mm (0.012 in)
76G01C-154
76G01C-155
7. If the end play is not within the specification, ad-
just the end play with an oversize thrust bearing.
Standard width:
2.00—2.05 mm (0.0787—0.0807 in)
Oversize width:
2.175—2.225 mm (0.0856—0.0876 in)
Note
First replace the rear thrust bearings, if still
not within the specification, replace the front
thrust bearings also.
1C-65