Mitsubishi 4G9 Automobile User Manual


 
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4G9 ENGINE (E-W) -
Cylinder Head and Valves
11A-9-9
PWEE9502-C
E
July 1997MitsubishiMotors Corporation
Revised
INSPECTION
CYLINDER HEAD
(1) Check the cylinder head gasket surface for flatness by
using a straightedge and thickness gauge.
Standard value: 0.03 mm
Limit: 0.2 mm
(2) If the service limit is exceeded, correct to meet the
specification.
Grinding limit:*0.2 mm
*Includes/combined with cylinder block grinding
Cylinder head height (Specification when new):
119.9 - 120.1 mm <SOHC>
131.9 - 132.1 mm <DOHC>
119.8 - 120.0 mm <DOHC-MIVEC>
131.9 - 132.1 mm <DOHC-GDI>
VALVE
(1) Check the valve face for correct contact. If incorrect,
reface using a valve refacer. Valve should make a uniform
contact with the seat at the centre of valve face.
(2) If the margin is smaller than the service limit, replace
the valve.
Standard value
mm
Limit mm
Intake 1.0 0.5
Exhaust SOHC 1.3 0.8
DOHC 1.2 0.7
(3) Measure the overall height of the valve. If the specified
limit is exceeded, replace the valve.
Standard value
mm
Limit mm
Intake SOHC 110.15 109.65
DOHC 104.19 103.69
DOHC-MIVEC 115.63 115.13
DOHC-GDI 104.19 103.69
Exhaust SOHC 113.70 113.20
DOHC 103.87 103.37
DOHC-MIVEC 115.63 115.13
DOHC-GDI 103.87 103.37
Valve seatcontact
Margin