Subaru Legacy IV (2008 year). Manual - part 272

ME(H4DOTC)-68

Cylinder Head

MECHANICAL

D: ASSEMBLY

(1)

Exhaust valve

(5)

Intake valve oil seal

(9)

Valve lifter

(2)

Intake valve

(6)

Valve spring

(10)

Exhaust valve oil seal

(3)

Cylinder head

(7)

Retainer

(11)

Intake valve guide

(4)

Valve spring seat

(8)

Retainer key

(12)

Exhaust valve guide

(3)

(1)

(2)

(11)

(4)

(5)

(6)

(7)

(8)

(9)

(11)

(12)

(12)

(10)

(4)

(4)

(5)

(6)

(6)

(7)

(7)

(8)

(8)

(9)

(9)

(10)

(4)

(6)

(7)

(8)

(9)

ME-03077

ME(H4DOTC)-69

Cylinder Head

MECHANICAL

1) Install the valve spring and valve.

(1) Coat the stem of each valve with engine oil
and insert the valve into the valve guide.

NOTE:
When inserting the valve into valve guide, use spe-
cial care not to damage the oil seal lip.

(2) Set the cylinder head on ST1.

ST1

498267600

CYLINDER HEAD TABLE

(3) Install the valve spring and retainer.

NOTE:
Be sure to install the valve spring with its close-
coiled end facing the seat on cylinder head.

(4) Set the ST2 on valve spring.

ST2

499718000

VALVE SPRING REMOVER

(5) Compress the valve spring and fit the valve
spring retainer key.
(6) After installing, tap the valve spring retainers
lightly with a plastic hammer for better seating.

2) Apply oil to the surface of valve lifter.
3) Install the valve lifter.

E: INSPECTION

1. CYLINDER HEAD

1) Check for cracks or damage. Use liquid pene-
trant tester on the important sections to check for
fissures. Check that there are no marks of gas leak-
ing or water leaking on gasket installing surface.
2) Measure the warping of the cylinder head sur-
face that mates with cylinder block using a straight
edge (A) and thickness gauge (B).
If the warping exceeds the limit, correct the surface
by grinding it with a surface grinder.

Warping limit:

0.035 mm (0.0014 in)

Grinding limit:

0.3 mm (0.012 in)

Standard height of cylinder head:

127.5 mm (5.02 in)

NOTE:
Uneven torque for the cylinder head bolts can
cause warping. When reinstalling, pay special at-
tention to the torque so as to tighten evenly.

ME-03142

ST1

ST2

ME-00126

(A)

(B)

ME(H4DOTC)-70

Cylinder Head

MECHANICAL

2. VALVE SEAT

Inspect the intake and exhaust valve seats, and
correct the contact surfaces with a valve seat cutter
if they are defective or when valve guides are re-
placed.

Valve seat width W:

Standard

Intake

0.6 — 1.4 mm (0.024 — 0.055 in)

Exhaust

1.2 — 1.8 mm (0.047 — 0.071 in)

3. VALVE GUIDE

1) Check the clearance between valve guide and
valve stem. The clearance can be checked by mea-
suring respectively the outer diameter of valve
stem with a micrometer and the inner diameter of
valve guide with a caliper gauge.

Clearance between the valve guide and valve 
stem:

Standard

Intake

0.030 — 0.057 mm (0.0012 — 0.0022 in)

Exhaust

0.040 — 0.067 mm (0.0016 — 0.0026 in)

2) If the clearance between valve guide and valve
stem exceeds the standard, replace the valve
guide or valve itself, whichever shows the greater
amount of wear or damage. See the following pro-
cedure for valve guide replacement.

Valve guide inner diameter:

6.000 — 6.012 mm (0.2362 — 0.2367 in)

Valve stem outer diameters:

Intake

5.955 — 5.970 mm (0.2344 — 0.2350 in)

Exhaust

5.945 — 5.960 mm (0.2341 — 0.2346 in)

(1) Place the cylinder head on ST1 with the
combustion chamber upward so that valve
guides fit the holes in ST1.
(2) Insert the ST2 into valve guide and press it
down to remove the valve guide.

ST1

498267600

CYLINDER HEAD TABLE

ST2

499767200

VALVE GUIDE REMOVER

ME-00127

W

ME-00287

ME-00128

ST1

ST2

ME(H4DOTC)-71

Cylinder Head

MECHANICAL

(3) Turn the cylinder head upside down and
place the ST as shown in the figure.

ST

18251AA020

VALVE GUIDE ADJUSTER

(4) Before installing a new valve guide, make
sure that neither scratches nor damages exist
on the inner surface of valve guide holes in cyl-
inder head.
(5) Put a new valve guide, coated with sufficient
oil, in the cylinder head, and insert the ST1 into
valve guide. Press in until the valve guide upper
end is flush with the upper surface of ST2.

ST1

499767200

VALVE GUIDE REMOVER

ST2

18251AA020 VALVE GUIDE ADJUSTER

(6) Check the valve guide protrusion.

Valve guide protrusion L:

15.8 — 16.2 mm (0.622 — 0.638 in)

(7) Ream the inside of valve guide using ST.
Put the ST in valve guide, and rotate the ST
slowly clockwise while pushing it lightly. Bring
the ST back while rotating it clockwise.

NOTE:
• Apply engine oil to the ST when reaming.
• If the inner surface of valve guide is damaged,
the edge of ST should be slightly ground with oil
stone.
• If the inner surface of valve guide becomes lus-
trous and the ST does not chip, use a new ST or
remedy the ST.
ST

499767400

VALVE GUIDE REAMER

(8) After reaming, clean the valve guide to re-
move chips.
(9) Recheck the contact condition between
valve and valve seat after replacing the valve
guide.

ME-00757

ST

L

ME-00130

ST1

ST2

ME-00294