1987 MAZDA 626 check oil

INSPECTION AND REPAIR 1C
-Clearance
3. Check the piston to cylinder clearance.
Clearance-
0.032—0.050 mm (0.0013—0.0020 in)
Maximum: 0.15 mm (0.0059 in)
4. If the clearance exceeds the maximum, replace the
piston or rebore the cylinders to fit oversize pistons.
Note
If the piston is replaced, replace the piston
rings also.
76G01C-134
69G01A-125
Piston and Piston Ring
1. Measure the piston ring to ring land clearance
around the entire circumference using a new pis-
ton ring.
Clearance (Top)
RF-CX: 0.18—0.22 mm (0.0071—0.0087 in)
RF-N : 0.05—0.09 mm (0.0020—0.0035 in)
Clearance (Second):
0.04—0.08 mm (0.0016—0.0031 in)
Maximum: 0.2 mm (0.008 in)
2.
If
the clearance exceeds the maximum, replace the
piston.
3. Inspect the piston rings for damage, abnormal
wear, or breakage. Replace if necessary.
4. Insert the piston ring into the cylinder by hand and
push it to the bottom of the ring travel in using the
piston.
86U01X-104
5. Measure each piston ring end gap with a feeler
gauge. Replace if necessary.
End gap (Top and second)
RF-CX: 0.20—0.35 mm (0.008—0.014 in)
RF-N : 0.20—0.40 mm (0.008—0.016 in)
End gap (Oil rail):
0.20—0.40 mm (0.008—0.016 in)
Maximum: 1.0 mm (0.039 in)

76G01C-144

1C-57

INSPECTION AND REPAIR 1C
Piston and Piston Pin
1. Measure the piston pin hole diameter in X and Y
directions at four points.
Diameter mm (in)
RF-CX 29.997-30.007 (1.1810-1.1814)
RF-N 24.997-25.007 (0.9841-0.9845)
76G01C-137
76G01C-139
2. Measure the piston pin diameter.
Diameter mm (in)
RF-CX 29.994-30.000 (1.1809-1.1811)
RF-N 24.994-25.000 (0.9840-0.9843)
3. Determine the piston pin to piston clearance by
subtracting the two figures.
Clearance-
-0.003—0.013 mm (0.0001—0.0005 in)
4. If the clearance exceeds the specification, replace
the piston and/or piston pin.
Connecting Rod
1. Measure the connecting rod small end bore.
Diameter mm (in)
RF-CX 30.014-30.030 (1.1817-1.1823)
RF-N 25.014-25.030 (0.9848-0.9854)
2. Check the clearance between the small end bore
and piston pin.
Clearance*
0.014—0.036 mm (0.0005—0.0015 in)
Maximum: 0.05 mm (0.002 in)
3. If the clearance exceeds the maximum, replace the
connecting rod bushing.
(1) Apply engine oil to the connecting rod and the
bushing.
(2) Align the oil holes of the connecting rod and
the bushing, and press the bushing in.
(3) Correct the bushing inner diameter, so that the
clearance is within the specification, by using
a spiral expansion reamer.

76G01C-144

1C-58

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

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

ASSEMBLY (TIMING BELT) 1 C
63G01D-431
76G01C-191
76G01C-192
Timing Belt Tensioner
1. Install the tensioner spring onto the tensioner.
2. Install the tensioner assembly.
3. Temporarily secure it so the tensioner is shifted
outward.
Timing Belt
1. Return the crankshaft about 45° to the timing mark
on the oil pump housing.
2. Check that the timing marks of the camshaft pul-
ley and the injection pump pulley align with the tim-
ing marks on the seal plate.
3. Install the timing belt in the sequence shown in the
figure.
Caution
The timing belt must be reinstalled in the same
direction of rotation for continued durability.

76G01C-200

1C—83