MAZDA 626 1987 Workshop Manual

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

1C INSPECTION AND REPAIR
Rolled fillet
Crankpin journal diameter undersize mm (in)
Bearing size Journal diameter
0.25 undersize 50.690—50.705 (1.9957-1.9963)
0.50 undersize 50.440—50.455 (1.9858-1.9864)
0.75 undersize 50.190-50.205 (1.9760-1.9766)
Caution
Do not grind the rolled fillet area.
76G01C-145
Main Bearing and Connecting Rod Bearing
Check the main bearings and the connecting rod
bearings for peeling, scoring, or other damage.
79G01C-077
Timing Belt
1. Replace the timing belt if there is any oil or grease
on it.
2. Check the timing belt for damage, wear, peeling,
cracks, or hardening. Replace if necessary.
86U01X-113
Caution
a) Never forcefully twist, turn inside out, or
bend the timing belt.
b) Be careful not to allow oil or grease on the
belt.
86U01X-114
1C—60

INSPECTION AND REPAIR 1C
86U01X-115
Timing Belt Tensioner and Idler Pulley
Check the timing belt tensioner and idler pulley for
smooth rotation and abnormal noise. Replace if
necessary.
Caution
Do not clean the tensioner with cleaning
fluids. If necessary, use a soft rag to wipe it
clean, and avoid scratching it.
Timing Belt Tensioner Spring
Check the free length of the tensioner spring. Replace
if necessary.
Free length:
52.6 mm (2.071 in)
76G01C-251
Timing Belt Pulley and Camshaft Pulley
Inspect the pulley teeth for wear, deformation, or other
damage. Replace if necessary.
Caution
Do not clean the pulley with cleaning fluids.
If necessary, use a rag to wipe it clean.
Timing Belt Cover
Inspect the timing belt covers for damage or cracks.
Replace if necessary.
76G01C-146
1C—61

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

1C ASSEMBLY (CYLINDER BLOCK)
Pilot Bearing
1. Apply engine oil to the outer circumference of the
bearing.
2. Set a piece of pipe (outer diameter 30—34 mm,
1.18—1.34 in) against the outer race of the bear-
ing, then tap it evenly into the crankshaft.
3. Lubricate the bearing with grease.
76G01C-156
Piston and Connecting Rod Assembly
1. Apply a liberal amount of clean engine oil to the
cylinder walls, piston, and rings.
2. Check the piston rings for the end gap alignment.
3. Insert each piston assembly into the cylinder block
with the "F" mark facing the front of the engine.
Use a piston installer tool (commercially available).
86U01X-128
Connecting Rod Cap
1. Check the connecting rod bearing clearances us-
ing the same procedure as used for the main bear-
ing oil clearance.
Connecting rod cap tightening torque:
65—69 N-m (6.6—7.0 m-kg, 48—51 ft-lb)
Oil clearance:
0.027—0.055 mm (0.0011—0.0022 in)
Maximum: 0.08 mm (0.0031 in)
76G01C-157
Caution
Align the alignment marks on the cap and on
the connecting rod when installing the con-
necting rod cap.
If the oil clearance exceeds the maximum, grind
the crankshaft and use undersize bearings. (Re-
fer to page 1C—60.)
76G01C-158
1C-66

ASSEMBLY (CYLINDER BLOCK) 1 C
3. Check the side clearance of each connecting rod
without the cap installed.
Side clearance:
0.11—0.262 mm (0.0043—0.0103 in)
Maximum: 0.30 mm (0.012 in)
If the clearance exceeds the maximum, replace the
connecting rod.
76G01C-159
4. Apply a liberal amount of engine oil to the crank-
pin journal and connecting rod bearing.
5. Install the connecting rod cap with the alignment
marks aligned.
Tightening torque:
65—69 Nm (6.6—7.0 m-kg, 48—51 ft-lb)
86U01X-130
Oil jet
Install the oil jet into the cylinder block.
Tightening torque: 12—18 N-m
(1.2—1.8 m-kg, 104—156 in-lb)
76G01C-160
1C-67

1 C ASSEMBLY (CYLINDER BLOCK)
CYLINDER BLOCK—II
Torque Specifications
179—193 N m (18.3—19.7 m-kg, 132—142 ft-lb)
—
I iu
uii-nn, 69—95 in-tb)
69G01A-166
Rear Cover
1. Apply engine oil to the rear cover, oil seal and oil
seal lip.
2. Press the oil seal into the rear cover.
4BG01A-158
1C-68