Pic. 2.147. Valve seat width measurement
Measure the width of the valve seat contact surface. If necessary, rework the valve seat or valve disc using the appropriate tool (pic. 2.147).
Standard width: 1.2-1.6 mm.
Pic. 2.148. Ways of processing a valve seat with a cutting tool
Check the alignment of the contact surface with respect to the valve seat (pic. 2.148).
If the contact surface is outwardly displaced, machine the valve seat with a cutting tool with a working angle of 70° (Inlet) or 65° (Release) and a cutting tool with an angle of 45°.
If the contact surface is displaced inwards, machine the valve seat with a cutting tool with a working angle of 30° (Inlet) or 0° (Release) and a cutting tool with an angle of 45°.
Pic. 2.149. Valve seat protrusion measurement
Check valve seat depth. Measure protrusion (size L) valve stem (pic. 2.149).
If the measured height is not correct, replace the cylinder head.
Standard size L:
- Intake: 40.64–42.24 mm;
- Outlet: 40.50–42.10 mm.