Yanmar 4JH4E - Engine Body; Cylinder Head

13. Service standards
319
13.2 Engine body
13.2.1 Cylinder head
(1) Cylinder head
(2) Intake/exhaust valve and guide
(3) Valve spring
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 -
Inspection item Standard Limit
Reference
page
3JH4E
4JH4E
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 -
4JH4-TE
4JH4-HTE
Intake
Guide inside diameter 6.000-6.015 6.1
5.2.3
Valve stem outside diameter 5.960-5.975 5.90
Clearance 0.025-0.055 0.16
Exhaust
Guide inside diameter 6.000-6.015 6.1
Valve stem outside diameter 5.945-5.960 5.90
Clearance 0.040-0.070 0.18
Valve guide projection from cylinder head 8.2-8.5 -
5.2.3(4)
Valve guide driving-in method Cold-fitted -
mm
Inspection item Standard Limit Reference page
Free length
3JH4E/ 4JH4E 44.4 43.0
5.2.4(1)4JH4-TE/ 4JH4-HTE 37.4 36.9
Inclination - 1.1