SUBARU LEGACY 1999 Service Repair Manual

2. CYLINDER AND PISTON
1) The cylinder bore size is stamped on the cylin-
der block's front upper surface.
CAUTION:
Measurement should be performed at a tem-
perature 20ÉC (68ÉF).
NOTE:
Standard sized pistons are classified into two
grades, ªAº and ªBº. These grades should be used
as a guide line in selecting a standard piston.
Standard diameter:
A: 96.905 Ð 96.915 mm (3.8151 Ð 3.8155
in)
B: 96.895 Ð 96.905 mm (3.8148 Ð 3.8151
in)
H2M1732A
2) How to measure the inner diameter of each
cylinder
Measure the inner diameter of each cylinder in
both the thrust and piston pin directions at the
heights shown in the figure, using a cylinder bore
gauge.
CAUTION:
Measurement should be performed at a tem-
perature 20ÉC (68ÉF).
Taper:
Standard
0.015 mm (0.0006 in)
Limit
0.050 mm (0.0020 in)
Out-of-roundness:
Standard
0.010 mm (0.0004 in)
Limit
0.050 mm (0.0020 in)
G2M0170
3) When piston is to be replaced due to general or
cylinder wear, determine a suitable sized piston by
measuring the piston clearance.
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6. Cylinder Block

4) How to measure the outer diameter of each
piston
Measure the outer diameter of each piston at the
height shown in the figure. (Thrust direction)
CAUTION:
Measurement should be performed at a tem-
perature of 20ÉC (68ÉF).
Piston grade point H:
40.0 mm (1.575 in)
Piston outer diameter:
Standard
A: 96.885 Ð 96.895 mm (3.8144 Ð 3.8148
in)
B: 96.875 Ð 96.885 mm (3.8140 Ð 3.8144
in)
0.25 mm (0.0098 in) oversize
97.125 Ð 97.135 mm (3.8238 Ð 3.8242 in)
0.50 mm (0.0197 in) oversize
97.375 Ð 97.385 mm (3.8337 Ð 3.8340 in)
B2M1305A
5) Calculate the clearance between cylinder and
piston.
CAUTION:
Measurement should be performed at a tem-
perature of 20ÉC (68ÉF).
Cylinder to piston clearance at 20ÉC (68ÉF):
Standard
0.010 Ð 0.030 mm (0.0004 Ð 0.0012 in)
Limit
0.050 mm (0.0020 in)
6) Boring and honing
(1) If the value of taper, out-of-roundness, or
cylinder- to-piston clearance measured exceeds
the specified limit or if there is any damage on
the cylinder wall, rebore it to use an oversize
piston.
CAUTION:
When any of the cylinders needs reboring, all
other cylinders must be bored at the same
time, and use oversize pistons. Do not perform
boring on one cylinder only, nor use an over-
size piston for one cylinder only.(2) If the cylinder inner diameter exceeds the
limit after boring and honing, replace the crank-
case.
CAUTION:
Immediately after reboring, the cylinder diam-
eter may differ from its real diameter due to
temperature rise. Thus, pay attention to this
when measuring the cylinder diameter.
Limit of cylinder enlarging (boring):
0.5 mm (0.020 in)
3. PISTON AND PISTON PIN
1) Check pistons and piston pins for damage,
cracks, and wear and the piston ring grooves for
wear and damage. Replace if defective.
2) Measure the piston-to-cylinder clearance at
each cylinder. If any of the
clearances is not to specification, replace the pis-
ton or bore the cylinder to use an oversize piston.
3) Make sure that piston pin can be inserted into
the piston pin hole with a thumb at 20ÉC (68ÉF).
Replace if defective.
Standard clearance between piston pin and
hole in piston:
Standard
0.004 Ð 0.008 mm (0.0002 Ð 0.0003 in)
Limit
0.020 mm (0.0008 in)
B2M1401
B2M0084A
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6. Cylinder Block

4) Check circlip installation groove on the piston
for burr. If necessary, remove burr from the groove
so that piston pin can lightly move.
B2M0420A
5) Check piston pin circlip for distortion, cracks
and wear.
4. PISTON RING
1) If piston ring is broken, damaged, or worn, or if
its tension is insufficient, or when the piston is
replaced, replace piston ring with a new one of the
same size as the piston.
CAUTION:
IªRº is marked on the end of the top and sec-
ond rings. When installing the rings to the
piston, face this mark upward.
G2M0623
IThe oil ring is a combined ring consisting of
two rails and a spacer in between. When
installing, be careful to assemble correctly.
G2M0624
2) Squarely place piston ring and oil ring in
cylinder, and measure the piston ring gap with a
thickness gauge.
Unit: mm (in)
Standard Limit
Piston
ring gapTop ring0.20 Ð 0.35
(0.0079 Ð 0.0138)1.0 (0.039)
Second
ring0.37 Ð 0.52
(0.0146 Ð 0.0205)1.0 (0.039)
Oil ring
rail0.20 Ð 0.50
(0.0079 Ð 0.0197)1.0 (0.039)
G2M0174
3) Measure the clearance between piston ring and
piston ring groove with a thickness gauge.
CAUTION:
Before measuring the clearance, clean the pis-
ton ring groove and piston ring.
Unit: mm (in)
Standard Limit
Clearance
between pis-
ton ring and
piston ring
grooveTop ring0.040 Ð 0.080
(0.0016 Ð
0.0031)0.15 (0.0059)
Second
ring0.030 Ð 0.070
(0.0012 Ð
0.0028)0.15 (0.0059)
B2M1402A
5. CONNECTING ROD
1) Replace connecting rod, if the large or small
end thrust surface is damaged.
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6. Cylinder Block

2) Check for bend or twist using a connecting rod
aligner. Replace connecting rod if the bend or twist
exceeds the limit.
Limit of bend or twist per 100 mm (3.94 in) in
length:
0.10 mm (0.0039 in)
B2M1005A
3) Install connecting rod fitted with bearing to
crankshaft and measure the side clearance (thrust
clearance). Replace connecting rod if the side
clearance exceeds the specified limit.
Connecting rod side clearance:
Standard
0.070 Ð 0.330 mm (0.0028 Ð 0.0130 in)
Limit
0.4 mm (0.016 in)
G2M0176
4) Inspect connecting rod bearing for scar,
peeling, seizure, melting, wear, etc.
5) )Measure the oil clearance on individual con-
necting rod bearings by means of plastigauge. If
any oil clearance is not within specification, replace
the defective bearing with a new one of standardsize or undersize as necessary. (See the table
below.)
Connecting rod oil clearance:
Standard
0.010 Ð 0.038 mm (0.0004 Ð 0.0015 in)
Limit
0.05 mm (0.0020 in)
Unit: mm (in)
BearingBearing size
(Thickness at cen-
ter)Outer diameter of
crank pin
Standard1.492 Ð 1.501
(0.0587 Ð 0.0591)51.984 Ð 52.000
(2.0466 Ð 2.0472)
0.03
(0.0012)
undersize1.510 Ð 1.513
(0.0594 Ð 0.0596)51.954 Ð 51.970
(2.0454 Ð 2.0461)
0.05
(0.0020)
undersize1.520 Ð 1.523
(0.0598 Ð 0.0600)51.934 Ð 51.950
(2.0446 Ð 2.0453)
0.25
(0.0098)
undersize1.620 Ð 1.623
(0.0638 Ð 0.0639)51.734 Ð 51.750
(2.0368 Ð 2.0374)
6) Inspect bushing at connecting rod small end,
and replace if worn or damaged. Also measure the
piston pin clearance at the connecting rod small
end.
Clearance between piston pin and bushing:
Standard
0 Ð 0.022 mm (0 Ð 0.0009 in)
Limit
0.030 mm (0.0012 in)
B2M0085
B2M0084A
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6. Cylinder Block

7) Replacement procedure is as follows.
(1) Remove bushing from connecting rod with
ST and press.
(2) Press bushing with ST after applying oil on
the periphery of bushing.
ST 499037100 CONNECTING ROD BUSH-
ING REMOVER AND
INSTALLER
G2M0177
(3) Make two 3 mm (0.12 in) holes in bushing.
Ream the inside of bushing.
(4) After completion of reaming, clean bushing
to remove chips.
6. CRANKSHAFT AND CRANKSHAFT
BEARING
1) Clean crankshaft completely and check for
cracks by means of red lead check etc., and
replace if defective.
2) Measure the crankshaft bend, and correct or
replace if it exceeds the limit.
CAUTION:
If a suitable V-block is not available, install #1
and #5 crankshaft bearing on cylinder block,
position crankshaft on these bearings and
measure crankshaft bend using a dial gauge.
Crankshaft bend limit:
0.035 mm (0.0014 in)
G2M0178
3) Inspect the crank journal and crank pin for
wear. If not to specifications, replace bearing with
an undersize one, and replace or recondition
crankshaft as necessary. When grinding crank
journal or crank pin, finish them to the specified
dimensions according to the undersize bearing to
be used.
Crank pin and crank journal:
Out-of-roundness
0.030 mm (0.0012 in) or less
Taper limit
0.07 mm (0.0028 in)
Grinding limit
0.250 mm (0.0098 in)
G2M0179
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6. Cylinder Block

Unit: mm (in)
Crank journal diameter
Crank pin diameter
#1, #5 #2, #3, #4
StandardJournal O.D.59.992 Ð 60.008
(2.3619 Ð 2.3625)59.992 Ð 60.008
(2.3619 Ð 2.3625)51.984 Ð 52.000
(2.0466 Ð 2.0472)
Bearing size
(Thickness at
center)1.998 Ð 2.011
(0.0787 Ð 0.0792)2.000 Ð 2.013
(0.0787 Ð 0.0793)1.492 Ð 1.501
(0.0587 Ð 0.0591)
0.03 (0.0012)
undersizeJournal O.D.59.962 Ð 59.978
(2.3607 Ð 2.3613)59.962 Ð 59.978
(2.3607 Ð 2.3613)51.954 Ð 51.970
(2.0454 Ð 2.0461)
Bearing size
(Thickness at
center)2.017 Ð 2.020
(0.0794 Ð 0.0795)2.019 Ð 2.022
(0.0795 Ð 0.0796)1.510 Ð 1.513
(0.0594 Ð 0.0596)
0.05 (0.0020)
undersizeJournal O.D.59.942 Ð 59.958
(2.3599 Ð 2.3605)59.942 Ð 59.958
(2.3599 Ð 2.3605)51.934 Ð 51.950
(2.0446 Ð 2.0453)
Bearing size
(Thickness at
center)2.027 Ð 2.030
(0.0798 Ð 0.0799)2.029 Ð 2.032
(0.0799 Ð 0.0800)1.520 Ð 1.523
(0.0598 Ð 0.0600)
0.25 (0.0098)
undersizeJournal O.D.59.742 Ð 59.758
(2.3520 Ð 2.3527)59.742 Ð 59.758
(2.3520 Ð 2.3527)51.734 Ð 51.750
(2.0368 Ð 2.0374)
Bearing size
(Thickness at
center)2.127 Ð 2.130
(0.0837 Ð 0.0839)2.129 Ð 2.132
(0.0838 Ð 0.0839)1.620 Ð 1.623
(0.0638 Ð 0.0639)
O.D. ... Outer Diameter
4) Measure the thrust clearance of crankshaft at
center bearing. If the clearance exceeds the limit,
replace bearing.
Crankshaft thrust clearance:
Standard
0.030 Ð 0.115 mm (0.0012 Ð 0.0045 in)
Limit
0.25 mm (0.0098 in)
G2M0180
5) Inspect individual crankshaft bearings for signs
of flaking, seizure, melting, and wear.
6) Measure the oil clearance on each crankshaft
bearing by means of plastigauge. If the measure-
ment is not within the specification, replace defec-
tive bearing with an undersize one, and replace or
recondition crankshaft as necessary.
Unit: mm (in)
Crankshaft oil clearance
Standard#1, #50.003 Ð 0.030
(0.0001 Ð
0.0012)
#2, #3, #40.010 Ð 0.033
(0.0004 Ð
0.0013)
Limit#1, #3, #5 0.040 (0.0016)
#2, #4 0.045 (0.0018)
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6. Cylinder Block

D: ASSEMBLY
1. CRANKSHAFT AND PISTON
B2M1320J
(1) Connecting rod bearing
(2) Connecting rod
(3) Connecting rod cap
(4) Oil ring(5) Second ring
(6) Top ring
(7) CirclipTightening torque: N´m (kg-m, ft-lb)
T:
44±2 (4.5±0.2, 32.5±1.4)
1) Install connecting rod bearings on connecting
rods and connecting rod caps.
CAUTION:
Apply oil to the surfaces of the connecting rod
bearings.
2) Install connecting rod on crankshaft.
CAUTION:
Position each connecting rod with the side
marked facing forward.
3) Install connecting rod cap with connecting rod
nut.
Ensure the arrow on connecting rod cap faces the
front during installation.
CAUTION:
IEach connecting rod has its own mating cap.
Make sure that they are assembled correctly by
checking their matching number.
IWhen tightening the connecting rod nuts,
apply oil on the threads.
4) Installation of piston rings and oil ring
(1) Install oil ring spacer, upper rail and lower
rail in this order by hand. Then install second
ring and top ring with a piston ring expander.(2) Position the top ring gap at (A) or (B) in the
figure.
B2M2635A
(3) Position the second ring gap at 180É on the
reverse side for the top ring gap.
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6. Cylinder Block

(4) Position the upper rail gap at (C) or (D) in
the figure.
B2M2636A
(5) Position the expander gap at 180É of the
reverse side for the upper rail gap.
(6) Position the lower rail gap at (E) or (F) in the
figure.
CAUTION:
IEnsure ring gaps do not face the same direc-
tion.
IEnsure ring gaps are not within the piston
skirt area.
B2M2636A
5) Install circlip.
Install circlips in piston holes located opposite ser-
vice holes in cylinder block, when positioning all
pistons in the corresponding cylinders.
CAUTION:
Use new circlips.
B2M1403A
CAUTION:
Piston front mark faces towards the front of the
engine.
B2M2800A
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6. Cylinder Block

2. CYLINDER BLOCK
B2M2407A
(1) Crankshaft bearing
(2) Crankshaft
(3) Cylinder block(4) Rear oil sealTightening torque: N´m (kg-m, ft-lb)
T1:
25±2 (2.5±0.2, 18.1±1.4)
T2:47±3 (4.8±0.3, 34.7±2.2)
1) Install ST to cylinder block, then install crank-
shaft bearings.
ST 499817000 ENGINE STAND
CAUTION:
Remove oil in the mating surface of bearing
and cylinder block before installation. Also
apply a coat of engine oil to crankshaft pins.
2) Position crankshaft on the #2 and #4 cylinder
block.3) Apply fluid packing to the mating surface of #1
and #3 cylinder block, and position it on #2 and #4
cylinder block.
Fluid packing:
THREE BOND 1215 or equivalent
CAUTION:
Do not allow fluid packing to jut into O-ring
grooves, oil passages, bearing grooves, etc.
G2M0185
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6. Cylinder Block

4) Temporarily tighten 10 mm cylinder block con-
necting bolts in alphabetical sequence shown in
figure.
B2M0088D
5) Tighten 10 mm cylinder block connecting bolts
in alphabetical sequence.
Tightening torque:
47
±3 N´m (4.8±0.3 kg-m, 34.7±2.2 ft-lb)
B2M0088D
6) Tighten 8 mm and 6 mm cylinder block connect-
ing bolts in alphabetical sequence shown in figure.
Tightening torque:
(A) Ð (G): 25
±2 N´m (2.5±0.2 kg-m,
18.1
±1.4 ft-lb)
(H): 6.4 N´m (0.65 kg-m, 4.7 ft-lb)
B2M0089F
7) Install rear oil seal using ST1 and ST2.
ST1 499597100 OIL SEAL GUIDE
ST2 499587200 OIL SEAL INSTALLER
G2M0186
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6. Cylinder Block