Inspection / Repair - Cylinder Head / Valve Mechanism

B2-74spec table

3
Inspect for the following and repair or replace the cylinder head if necessary: (1) Sunken valve seats; (2) Damaged intake and exhaust manifold contact surfaces; (3) Excessive camshaft oil clearances and end play.
4
If the cylinder head distortion exceeds the specification, replace the cylinder head or grind the cylinder head surface.
5
If the cylinder head height is not within the specification, replace it.
6
Measure the intake and exhaust manifold contact surfaces for distortion in the six directions as shown.
7
If distortion exceeds the specification, grind the surface or replace the cylinder head.

Specification	Value
Grindingmax.	0.15 {0.006}mm {in}
Height	133.4-133.6 {5.252-5.259}mm {in}
Distortion (manifold contact surfaces)max.	0.10 {0.004}mm {in}

Grindingmax.

0.15 {0.006}mm {in}

Height

133.4-133.6 {5.252-5.259}mm {in}

Distortion (manifold contact surfaces)max.

0.10 {0.004}mm {in}

VALVE MECHANISM

1
Inspect each valve for the following. Replace or resurface the valve as necessary: (1) Damaged or bent stem; (2) Rough or damaged face; (3) Damaged or unevenly worn stem tip.
2
Measure the valve head margin thickness. Replace the valve if necessary.
3
Measure the valve length. Replace the valve if necessary.
4
Measure the valve stem diameter. Replace the valve if necessary.
5
Measure the valve guide inner diameter. Replace the guide if necessary.

Margin thicknessIN: min.

0.9 {0.035}mm {in}

Margin thicknessEX: min.

1.0 {0.039}mm {in}

LengthStandard IN

94.11 {3.7051}mm {in}

LengthStandard EX

95.19 {3.7476}mm {in}

LengthMinimum IN

93.61 {3.6854}mm {in}

LengthMinimum EX

94.69 {3.7279}mm {in}

DiameterStandard IN

5.970-5.985 {0.2351-0.2356}mm {in}

DiameterStandard EX

5.965-5.980 {0.2349-0.2354}mm {in}

DiameterMinimum IN

5.920 {0.2331}mm {in}

DiameterMinimum EX

5.915 {0.2329}mm {in}

Inner diameterIN

6.01-6.03 {0.2367-0.2374}mm {in}

Inner diameterEX

6.01-6.03 {0.2367-0.2374}mm {in}