1989 MAZDA 323 Factory Repair Manual

DISASSEMBLY
03UOBZO7i
Main bearing cap
1. Before removing the main bearing caps, measure the crank-
shaft end play. (Refer to page 62-70.)
2. Loosen the main bearing cap bolts in two or three steps
in the order shown in the figure.
3. Remove the main bearing caps.
Crankshaft
1. Before removing the crankshaft, measure the main bear-
ing oil clearances. (Refer to page 82-69.)
03UOB2-079
B2-53

I32 INSPECTION / REPAIR
INSPECTION / REPAIR
PREPARATION
SST
49 6012 005 49 6012 005
Remover & Remover &
installer, valve installer, valve
guide guide
49 LO12 002
Body
(Part of
49 LO12 OAO)
49 LO12 004
Nut
(Part of
49 LO12 OAO) For
removal of
valve guide
For
installation of
valve guide
For
installation of
valve guide 49 LO12 OAO
Installer set,
valve seal &
valve guide
49 LO12 003
Installer
(Part of
49 LO12 OAO) For
installation of
valve guide
For
installation of
valve guide
05UOBX-1
1. Clean all parts, being sure to remove all gasket fragments, dirt, oil or grease, carbon, moisture residue,
and other foreign materials.
2. Inspection and repairs must be performed in the order specified. -.,
Caution
l Do not damage the joints or friction surfaces of aluminum alloy components (such as the cyl-
inder head or pistons).
0311082-162
03UOB2-70 OWOBX-119
CYLINDER HEAD
1, Inspect the cylinder head for damage, cracks, and leakage
of water and oil. Replace the cylinder head if necessary.
2. Measure the cylinder head distortion in the six directions
shown in the figure.
Distortion: O.lOmm (0.004 in) max.
Cautlon
l Before grinding the cylinder head, check the follow-
ing and repair or replace the cylinder head as
necessary.
Sinking of valve seats
Damage of manifold contact surface
Camshaft oil clearances and end play
3. If the cylinder head distortion exceeds specification, grind
the cylinder head surface.
If the cylinder head height is not within specification, replace
it. Height: 133.8-l 34.0mm (5.268-5.276
in)
Grinding: O.lOmm (0.004 in) max.
62-64

INSPECTION / REPAIR B2
0311082-007
I!!?
STEM TIP
23UOBZ03f
23UOW03i
IL VALVE STEM
OWOBX-125 CLEARANCE
4. Measure the manifold contact surface distortion in the four
directions shown in the figure.
Distortion: 0.15mm (0.006 In) max.
5. If distortion exceeds specification, grind the surface or re-
place the cylinder head.
VALVE MECHANISM
Valve and Valve Guide
1. inspect each valve for the following. Replace or resurface
the valve if necessary.
(1) Damaged or bent stem.
(2) Rough or damaged face.
(3) Damaged or unevenly worn stem tip.
2. Measure the valve head margin thickness of each valve.
Replace the valve if necessary.
Margin thickness
IN : 0.9mm (0.0354 in)
EX: l.Omm (0.0394 in)
3. Measure the length of each valve.
Length
Standard
IN : 101.34mm (3.9696 in)
EX: 101.44mm (3.9937 in)
Minimum
IN : 100.64mm (3.9701 in)
EX: 100.94mm (3.9740 in)
4. Measure the stem diameter of each valve at the points
shown.
Diameter
IN : 5.970-5965mm (0.2350-0.2356 in)
EX: 5.965-5960mm (0.2346-0.2354 in)
5. Measure the inner diameter of each valve guide at the points
shown.
Inner diameter
IN : 6.01-6.03mm (0.2366-0.2374 in)
EX: 6.01-6.03mm (0.2366-0.2374 in)
6. Calculate the valve stem to guide clearance.
Subtract the outer diameter of the valve stem from the in-
ner diameter of the corresponding valve guide.
Clearance
IN : 0.025-0.060mm (0.0010-0.0024 in)
EX: 0.030-0.065mm (0.0012-0.0026 in)
Maximum: 0.20mm (0.006 in)
7. If the clearance exceeds specification, replace the valve
and/or valve guide.
B2-55

82 INSPECTION / REPAIR
03UOB2-082
13UOB2-0.
1
9MUOB2-112
I
03UOB2-08:
8. Measure the height @of each valve guide. Replace the
valve guide if necessary.
Height: 18.3-l 8.9mm (0.720-0.744 in)
Replacement of valve guide
Note
l The valve guides are different between intake and
exhaust sides, use the correct valve guide.
Removal
1. Remove the valve guide from the side opposite the com-
bustion chamber with the
SST.
Installation
1. Assemble the SST so that depth L is as specified.
Depth L: 18.3-18.9mm (0.720-0.744 in)
2. lighten the locknut.
3. Tap the valve guide in from the side opposite the combus-
tion chamber until the
SST contacts the cylinder head.
4. Verify that the valve guide height is within specification.
5. If not within specification, repeat Steps 1-4.
82-56

INSPECTION / REPAIR 82
OWOBX-13
SEAT CONTACT WIDTH
I OWOBX-132
IN EX
700
Li!!b!J
700
45O 450
r
----
0311082 Oe
_---- _---
1
05UOBX-1:
Gi
Valve Seat
1, Inspect the contact surface of each valve seat and valve
face for the following:
(1) Roughness.
(2) Damage.
2. If necessarv, resurface the valve seat with a 45’ valve seat
cutter and/br resurface the valve face.
3. Apply a thin coat of Prussian blue to the valve face.
4. Inspect the valve seating by pressing the valve against the
seat.
(1) If blue does not appear 360° around the valve face, re-
place the valve.
(2) If blue does not appear 360° around the valve seat,
resurface the seat.
5. Measure the seat contact width.
Width: 0.8-l .4mm (0.031-0.055 in)
6. Verify that the valve seating position is at the center of the
valve face.
(1) If the seating position is too high, correct the valve seat
with a 70° cutter and a 45O cutter.
(2) If the seating position is too low, correct the valve seat
with a O” cutter and a 45’ cutter.
7. Seat the valve to the valve seat with lapping compound.
8. Inspect the sinking of the valve seat.
B2-57

B2 INSPECTION / REPAIR
23UOB2-060
i$
03UOB2-08
ANGLE LIMIT
Ii
0311082.Ot
w v
05UOBX-138
03UOB2-OE
82-58
I8
9. Measure the protruding length (dimension L) of the valve
stem.
Dimension L: 45.0mm (1.7717 in)
(1) If L is 45.0-45.5mm (1.772-l .791 in), no correc-
tion needed.
(2) If L is 45.5-46.5mm (1.791-l .831 in), adjust with
washer on spring seat area of cylinder head.
(3) If L is 46.5mm (1.831 in) or more, replace cylinder
head.
Valve Spring
1. Inspect each valve spring for cracks or damage.
2. Measure the free length and out-of-square. Replace the
valve spring if necessary.
Free length
Standard: 46.26mm (1.821 in)
Minimum:
224-253 N (22.8-25.8 kg, 50-57 lb)/
395mm (1.555 in)
Out-of-square: 1.62mm (0.064 in) max.
CAMSHAFT
1. Set the front and rear journals on V-blocks.
2. Measure the camshaft runout. Replace the camshaft if
necessary.
Runout: 0.03mm (0.0012 in) max.
3. Inspect the camshaft for wear or damage. Replace the cam-
shaft if necessary.
4. Measure the cam lobe heights at the two points as shown.
Height
Standard
IN : 44.094mm (1.7360 in)
EX: 44.600mm (1.7560 in)
Minimum
IN : 43.894mm (1.7281 in)
EX: 44.400mm (1.7480 in)

INSPECTION / REPAIR B2
23UOB2-06
051JOBX.14
05UOBX.14
OWOBX-14
05UOBX-14
5. Measure the journal diameters in X and Y directions at the
two points (A and 8) shown.
Diameter:
25.940-25.965mm (1.0213-l .0222 in)
Out-of-round: 0.03mm (0.001 in) max.
6. Measure the camshaft journal oil clearances.
Caution
l Do not install the HLA when measuring the oil
clearance.
(1) Remove all foreign material and oil from the journals and
bearing surface.
(2) Set the camshaft onto the cylinder head.
(3) Position Plastigage atop the journals in the axial
direction.
(4) Install the camshaft caps according to the cap number
and arrow mark.
(5) Install the camshaft cap bolts and tighten them in two
or three steps in the order shown in the figure.
Tightening torque:
11.3-14.2 N-m (1.15-l .45 m-kg, loo-126 in-lb)
(6) Loosen the camshaft cap bolts in two or three steps in
the order shown in the figure.
(7) Remove the camshaft caps.
82-59

B2 INSPECTION / REPAIR
r--
1
05UOBX-14
I -
L
05UOBX-149
82-60
(8) Measure the oil clearances.
Oil clearance:
0.035-0.081 mm (0.0014-0.0032 in)
Maximum: 0.15mm (0.006 in)
(9) If the oil clearance exceeds specification, replace the
cylinder head.
7. Measure the camshaft end play. If the end play exceeds
specification, replace the camshaft and/or the cylinder head.
End play : 0.07-0.19mm (0.0028-0.0075 in)
Maximum: 0.20mm (0.008 in)
HLA
Caution
l Do not attempt to repair the HLA.
1, Inspect the HLA friction surfaces for wear or damage. Re-
place the HLA if necessary.
2. Hold the bucket body and press the plunger by hand. If
the plunger moves, replace the HLA.
CYLINDER BLOCK
1. Inspect the cylinder block for the following. Repair or re-
place the cylinder block as necessary.
(1) ‘Leakage damage.
(2) Cracks.
(3j Scoring of wall.
2. Measure the distortion of the top surface of the cylinder block
in the six directions shown in the figure.
Distortion: 0.15mm (0.006 in) max.
3. If the distortion exceeds specification, repair by grinding’or
replace the cylinder block.
Height : 221 Smm (8.720 in)
Grinding: 0.20mm (0.008 in) max.