Removal
1. Insert adapter 1 into the spark plug hole and apply air pressure to the combustion chamber (minimum 5 bar), only if the cylinder head is installed on the cylinder block (see figure 2.37).
Figure 2.37. Insert adapter 1 into the spark plug hole and apply air pressure to the combustion chamber (minimum 5 bar).
2. Install guide sleeve 3 into the cylinder head, screw fastening tool 2 into the cylinder head.
3. Install the guide device 5 (see figure 2.38).
Figure 2.38. Install guide device 5.
4. Install cartridge 4 into guide sleeve 3, attach guide device 5 to fastening tool 2 and lightly tighten it onto the two bolts of cartridge 4. Using light pressure of the guide device, slowly rotate the knurled bolt on the cartridge to the right (arrow) until the felt is correctly installed in the slot between the valve sleeves.
5. Press the guide device 5 down until it stops completely (arrow) (see figure 2.39). After this, press your finger on the knurled bolt of the chuck 4 (arrow). The guide device 5 must be installed vertically (if possible) on cartridge 4 to avoid jamming of cartridge 4.
Figure 2.39. Press guide device 5 down until it stops completely (arrow).
6. Loosen chuck 4 and guide device 5 and remove them. The valve crackers are removed automatically.
7. Check that crackers 6 are in cartridge 4, repeat steps 4 through 6 if necessary (see figure 2.40).
Figure 2.40. Check that the crackers are in the chuck.
8. Remove guide bush 3, spring retainer 7 and spring 8 (see figure 2.41).
Figure 2.41. Remove guide sleeve 3, spring retainer 7 and spring 8.
9. Remove the valve stem seal 1 using pliers 9 (see figure 2.42).
Figure 2.42. Remove the valve stem seal using pliers.
10. Remove the spring plate, check for damage and, if necessary, replace it and install a new one.
11. Install the protective cover 11 on the valve stem (see figure 2.43).
Figure 2.43. Install the protective cover on the valve stem.
12. Install the new retainer 10 on the valve stem and press it in using tool 12.
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13. Remove the protective cover 11.
14. Install spring 8 and spring retainer 7 (see figure 2.44).
Figure 2.44. Install the spring and spring retainer.
15. Install guide sleeve 3 into the cylinder head (see figure 2.45).
Figure 2.45. Installing valve crackers.
16. Install cartridge 4 with valve crackers and insert them into guide sleeve 3, hooking lever 5 to fastening tool 2, and lightly tighten it onto two bolts of cartridge 4. Press guide device 5 down until it stops completely (arrow). Then remove the knurled bolt from cartridge 4 (arrow) and after a while loosen guide device 5 (see figure 2.45). The crackers are installed automatically.
17. Remove all additional tools from the cylinder head, except for the adapter with connector 1.
18. Check the correct installation of crackers 6. Remove the air supply hose from the cylinder head with the adapter (see figure 2.46).
Figure 2.46. Checking the installation of valve crackers.