Yanmar 3JH4CE - Engine Body; Cylinder Head

13. SERVICE STANDARDS
192
13.2 Engine Body
13.2.1 Cylinder head
(1) Cylinder head
(2) Intake/exhaust valve and guide
(3) Valve spring
(4) Rocker arm and shaft
(5) Push rod
Inspection item Standard Limit Reference page
Combustion surface distortion mm 0.05 or less 0.15 5.2.1(1)
Valve sink
mm
Intake
Exhaust
0.30-0.50 0.8 5.2.3(3)
Valve seat Seat angle Deg.
Intake 120 -
5.2.1(3)
Exhaust 90 -
mm
Inspection item Standard Limit Reference page
Intake
Guide inside diameter 8.010-8.025 8.10
5.2.3
Valve stem outside diameter 7.955-7.975 7.90
Clearance 0.035-0.070 0.18
Exhaust
Guide inside diameter 8.015-8.030 8.10
Valve stem outside diameter 7.955-7.970 7.90
Clearance 0.045-0.075 0.18
Valve guide projection from cylinder head 14.7-15.0 -
5.2.3(4)
Valve guide driving-in method Cold-fitted -
mm
Inspection item Standard Limit Reference page
Free length 44.4 43.0
5.2.4(1)
Inclination - 1.1
mm
Inspection item Standard Limit Reference page
Arm shaft hole diameter 16.000-16.020 16.090
5.2.7(1)Shaft outside diameter 15.966-15.984 15.955
Clearance 0.016-0.054 0.140
mm
Inspection item Standard Limit Reference page
Bend Less than 0.03 0.03 5.6.2(3)