Subaru Legacy III (2000-2003 year). Manual - part 67

ME(H4SO)-80

MECHANICAL

CYLINDER BLOCK

NOTE:
Ensure that the total “re-tightening angle” [in the
former two steps], do not exceed 180º.

30) Install the oil level gauge guide, and then tight-
en the attaching bolt (left side only).
31) Install the rocker cover.

32) Install the crankshaft sprocket. <Ref. to
ME(H4SO)-53, INSTALLATION, Crankshaft
Sprocket.>
33) Install the camshaft sprocket. <Ref. to
ME(H4SO)-51, INSTALLATION, Camshaft
Sprocket.>
34) Install the timing belt assembly. <Ref. to
ME(H4SO)-47, INSTALLATION, Timing Belt As-
sembly.>
35) Install the belt cover. <Ref. to ME(H4SO)-45,
INSTALLATION, Belt Cover.>
36) Install the crankshaft pulley. <Ref. to
ME(H4SO)-43, INSTALLATION, CRANKSHAFT
PULLEY.>
37) Install the generator and A/C compressor
brackets on cylinder head.
38) Install the V-belt. <Ref. to ME(H4SO)-42, IN-
STALLATION, V-belt.>
39) Install the intake manifold. <Ref. to FU(H4SO)-
17, INSTALLATION, Intake Manifold.>

C: DISASSEMBLY

1) Remove the connecting rod cap.
2) Remove the connecting rod bearing.

NOTE:
Arrange the removed connecting rod, connecting
rod cap and bearing in order to prevent confusion.
3) Remove the piston rings using the piston ring ex-
pander.
4) Remove the oil ring by hand.

NOTE:
Arrange the removed piston rings in good order to
prevent confusion.
5) Remove the circlip.

(A) Front

( a )

( b )

( c )

( A )

( d )

( e )

( f )

ME-00309

(1) Connecting rod cap

(3) Top ring

(5) Oil ring

(2) Connecting rod bearing

(4) Second ring

(6) Circlip

( 3 )

( 4 )

( 5 )

( 6 )

( 2 )

( 1 )

ME-00168

ME(H4SO)-81

MECHANICAL

CYLINDER BLOCK

D: ASSEMBLY

1) Apply oil to the surfaces of the connecting rod
bearings.
2) Install the connecting rod bearings on connect-
ing rods and connecting rod caps.
3) Position each connecting rod with the marked
side facing forward, and then install them.
4) Install the connecting rod cap with connecting
rod nut.
Ensure the arrow on connecting rod cap faces the
front during installation.

NOTE:
• Each connecting rod has its own mating cap.
Make sure that they are assembled correctly by
checking their matching number.
• When tightening the connecting rod nuts, apply
oil on the threads.
5) Install the expander, lower rail and upper rail in
this order by hand. Then install the second ring and
top ring with a piston ring expander.

E: INSPECTION

1. CYLINDER BLOCK

1) Visually check for cracks and damage. Especial-
ly, inspect the important parts by means of red lead
check.
2) Check the oil passages for clogging.
3) Inspect the crankcase surface that mates with
cylinder head for warping by using a straightedge,
and correct by grinding if necessary.

Warping limit:

0.05 mm (0.0020 in)

Grinding limit:

0.1 mm (0.004 in)

Standard height of cylinder block:

201.0 mm (7.91 in)

2. CYLINDER AND PISTON

1) The cylinder bore size is stamped on cylinder
block's front upper surface.

NOTE:
• Measurement should be performed at a temper-
ature of 20

C (68

F).

• Standard sized pistons are classified into two
grades, “A” and “B”. These grades should be used
as a guide line in selecting a standard piston.

(1) Connecting rod bearing

(5) Second ring

Tightening torque: N·m (kgf-m, ft-lb)

(2) Connecting rod

(6) Top ring

T: 45 (4.6, 33)

(3) Connecting rod cap

(7) Circlip

(4) Oil ring

(8) Side mark

( 2 )

( 7 )

( 4 )

( 5 )

( 6 )

( 1 )

ME-00392

( 3 )

( 8 )

ME(H4SO)-82

MECHANICAL

CYLINDER BLOCK

Standard diameter:

2000 cc model

A: 92.005 — 92.015 mm (3.6222 — 3.6226
in)
B: 91.995 — 92.005 mm (3.6218 — 3.6222
in)

2500 cc model

A: 99.505 — 99.515 mm (3.9175 — 3.9179
in)
B: 99.495 — 99.505 mm (3.9171 — 3.9175
in)

2) How to measure the inner diameter of each cyl-
inder
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.

NOTE:
Measurement should be performed at a tempera-
ture of 20

C (68

F).

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)

3) When the piston is to be replaced due to general
or cylinder wear, determine a suitable sized piston
by measuring the piston clearance.
4) How to measure the outer diameter of each pis-
ton
Measure the outer diameter of each piston at the
height shown in the figure. (Thrust direction)

NOTE:
Measurement should be performed at a tempera-
ture of 20

C (68

F).

Piston grade point H:

• 2000 cc model

40.0 mm (1.575 in)

• 2500 cc model

37.0 mm (1.457 in)

(A) Main journal size mark

(B) Cylinder block RH-LH combination mark

(D) #2 cylinder bore size mark

(E) #3 cylinder bore size mark

(F) #4 cylinder bore size mark

ME-00170

( B )

( C )

( D )

( E )

( F )

( A )

(A) Piston pin direction

(B) Thrust direction

H1 10 mm (0.39 in)

H2 45 mm (1.77 in)

H3 80 mm (3.15 in)

H4 115 mm (4.53 in)

ME-00171

( A )

( B )

ME(H4SO)-83

MECHANICAL

CYLINDER BLOCK

Piston outer diameter:

Standard:

• 2000 cc model

A: 91.985 — 91.995 mm
(3.6214 — 3.6218 in)
B: 91.975 — 91.985 mm
(3.6211 — 3.6214 in)

0.25 mm (0.0098 in) oversize

92.225 — 92.235 mm
(3.6309 — 3.6313 in)

0.50 mm (0.0197 in) oversize

92.475 — 92.485 mm
(3.6407 — 3.6411 in)

• 2500 cc model

A: 99.485 — 99.495 mm
(3.9167 — 3.9171 in)
B: 99.475 — 99.485 mm
(3.9163 — 3.9167 in)

0.25 mm (0.0098 in) oversize

99.725 — 99.735 mm
(3.9262 — 3.9266 in)

0.50 mm (0.0197 in) oversize

99.975 — 99.985 mm
(3.9360 — 3.9364 in)

5) Calculate the clearance between cylinder and
piston.

NOTE:
Measurement should be performed at a tempera-
ture of 20

C (68

F).

Cylinder to piston clearance at 20

°°°°

C (68

°°°°

F):

Standard

0.010 — 0.030 mm (0.0004 — 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 pis-
ton.

NOTE:
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 cyl-
inder only, nor use an oversize piston for one cylin-
der only.

(2) If the cylinder inner diameter exceeds the
limit after boring and honing, replace the crank-
case.

NOTE:
Immediately after reboring, the cylinder diameter
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 the 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. <Ref. to ME(H4SO)-81, CYLINDER
BLOCK, INSPECTION, Cylinder Block.> If any of
the clearances is not to specification, replace the
piston or bore the cylinder to use an oversize pis-
ton.

ME-00172

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