Illustration
- 1. Cylinder head height
- 2. Installation height of valve guide
- 3. Installation height of valve
- 4. Valve seat width in cylinder head
- 5. Valve seat angle in cylinder head
- 6. Valve stem diameter
- 7. Valve seat angle at valve
- 8. Valve length
- 9. Valve head – diameter
| Engine | | Z 18 XER |
| Cylinder head height 1) | mm | |
| Valve seat width in cylinder head | | |
| Intake valve | mm | 1.0 - 1.4 |
| Exhaust valve | mm | 1.4 - 1.8 |
| Valve seat angle in cylinder head | | 90° -30' |
| Valve guide inside diameter | | |
| Standard size | mm | 5.000 - 5.016 |
| Oversize (0.075) | mm | 5.075 - 5.091 |
| Oversize (0.150) | mm | 5.150 - 5.166 |
| Length of valve guide | | |
| Intake valve | mm | 36.7 - 37.3 |
| Exhaust valve | mm | 36.7 - 37.3 |
| Installation height of valve guide | | |
| Intake valve | mm | 10.7 - 11.0 |
| Exhaust valve | mm | 10.7 - 11.0 |
| Installation height of valves | | |
| Standard size | mm | 47.75 |
| Engine | | Z 18 XER |
| Valve length | | |
| Standard size | | |
| | Intake valve (GM F) | mm | 117.10 - 117.30 |
| | Exhaust valve (GM B) | mm | 116.16 - 116.36 |
| Oversize (0.075) | | |
| | Intake valve (GM FK1) | mm | 102.52 - 102.92 |
| | Exhaust valve (GM BK1) | mm | 101.62 - 102.02 |
| Oversize (0.150) | | |
| | Intake valve (GM FK2) | mm | 102.52 - 102.92 |
| | Exhaust valve (GM BK2) | mm | 101.62 - 102.02 |
| Ø | Valve stem | | |
| Standard size | | |
| | Intake valve (GM F) | mm | 4.955 - 4.970 |
| | Exhaust valve (GM B) | mm | 4.935 - 4.950 |
| Oversize (0.075) | | |
| | Intake valve (GM FK1) | mm | 5.030 - 5.045 |
| | Exhaust valve (GM BK1) | mm | 5.010 - 5.025 |
| Oversize (0.150) | | |
| | Intake valve (GM FK2) | mm | 5.105 - 5.120 |
| | Exhaust valve (GM BK2) | mm | 5.085 - 5.100 |
| Engine | | Z 18 XER |
| Valve stem play | | |
| Intake valve | mm | 0.030 - 0.061 |
| Exhaust valve | mm | 0.050 - 0.081 |
| Perm. runout of the valve stem | mm | 0.03 |
| Ø Valve head | | |
| Intake valve | mm | 30.7 - 30.8 |
| Exhaust valve | mm | 27.1 - 27.2 |
| Valve seat angle at valve head | | 90° 40' |
| Valve rotator | | |
| Intake valve | | none |
| Exhaust valve | | none |
| Engine | | Z 18 XER |
| Camshaft | | |
| Cam lift | | |
| | Intake | mm | 9.3 |
| | Exhaust | mm | 8.3 |
| Engine | | Z 18 XER |
| Valve clearance | | |
| Nominal values | | |
| | Intake | mm | 0,25 |
| | Exhaust | mm | 0,30 |
| Permitted valve play | | |
| | Intake | mm | 0.21 - 0.29 |
| | Exhaust | mm | 0.27 - 0.35 |
| Valve lifter steps for service |
| Engine | | Z 18 XER |
| Coefficient | | Dimension |
| 04 | mm | 3.030 - 3.050 |
| 08 | mm | 3.070 - 3.090 |
| 12 | mm | 3.110 - 3.130 |
| 16 | mm | 3.150 - 3.170 |
| 20 | mm | 3.190 - 3.210 |
| 24x | mm | 3.230 - 3.244 |
| 27x | mm | 3.258 - 3.272 |
| 30x | mm | 3.286 - 3.300 |
| 32x | mm | 3.314 - 3.328 |
| 35x | mm | 3.342 - 3.356 |
| 38x | mm | 3.370 - 3.384 |
| 41x | mm | 3.398 - 3.412 |
| 43x | mm | 3.426 - 3.440 |
| 47 | mm | 3.460 - 3.480 |
| 51 | mm | 3.500 - 3.520 |
| 55 | mm | 3.540 - 3.560 |
| 59 | mm | 3.580 - 3.600 |
) Flattening the cylinder head is not permitted.