Subaru 2009 IMPREZA, Руководство по обслуживанию

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ME(H4SO)-68
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.
Contacting width W between valve and valve seat:
Standard:
Intake (A)
0.8 — 1.4 mm (0.03 — 0.055 in)
Exhaust (B)
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
0.035 — 0.062 mm (0.0014 — 0.0024 in)
Exhaust
0.040 — 0.067 mm (0.0016 — 0.0026 in)
2) If the clearance between the valve guide and
valve stem exceeds the standard, replace the valve
guide or valve itself, whichever shows 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
5.950 — 5.965 mm (0.2343 — 0.2348 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.
W
W
(A) (B)
ME-00397
ME-00287
(A) Valve guide
ME-00763
(A)
ME-00289
X
Y