Removal
1. Remove the valve spring.
2. Remove the valves.
3. Remove the glow plugs.
4. Remove the injector holder.
Examination
5. Check the valve guides (figure 2.27). To do this:
Figure 2.27. Location of the guide bushing in the cylinder head: 1 - Cylinder head; 2 - Valve guide bushing; 3 - Valve seat ring; a - Main diameter of the guide bushing.
- clean the valve guide bore thoroughly (figure 2.28);
Figure 2.28. Clean the valve guide bore thoroughly.
- insert punch 4 into the hole for the guide bushing. If it can be inserted at some distance (for exhaust valves - 9 mm, intake - 8 mm), replace the guide bushing (figure 2.29).
Figure 2.29. Insert punch 4 into the hole for the guide bushing.
Replacement
6. Using punch 5, knock out the old guide bushing 2 from the cylinder head upwards (figure 2.30).
Figure 2.30. Knock out guide bushing 2 using punch 5.
Boring a hole
7. Remove carbon deposits and thoroughly wipe the cylinder head, in particular the side of the valve seat rings.
8. Remove the tabs (arrow) on the valve seat ring (figure 2.31).
Figure 2.31. Remove the tabs (arrow) on the valve seat ring.
9. Select the required boring tool and the required guide bushing according to Table 2.3.
Table 2.3. Selection of boring tool and guide bushing
| Valve seat | Boring tool number | Guide bushing number | Letter on the guide bushing |
| Inlet | 115 589 00 53 00 (14.2 mm) | 102 589 00 63 00 | IN |
| Outlet | 115 589 01 53 00 (14.2 mm) | 102 589 08 63 00 | IN |
| Inlet | 115 589 01 53 00 (14.4 mm) | 601 589 15 63 00 | A |
| Outlet | 115 589 01 53 00 (14.4 mm) | 601 589 15 63 00 | IN |
10. Using a stiff brush or similar tool, scrub the surface to be bored before boring.
11. Generously lubricate the main bore, guide bushing and boring tool with mineral oil.
12. Insert boring tool 6 in the boring direction into the guide sleeve so that the first blade of the boring tool is located in the main hole when the guide sleeve is located on the valve seat ring 3 (figure 2.32).
Figure 2.32. Insert boring tool 6 in the boring direction into the guide sleeve so that the first blade of the boring tool is located in the main hole when the guide sleeve is located on the valve seat ring 3.
13. Center the guide sleeve 7 in the valve seat ring 3 by rotating it.
14. Using a plastic hammer (weighing approximately 250 g) and an aluminum punch, quickly drive in the boring tool (figure 2.33).
Figure 2.33 Using a plastic hammer and an aluminum punch, quickly tap in the boring tool.
Heat
15. Attach cylinder head 1 to the lift and heat it in a water bath (figure 2.34).
Figure 2.34. Attach cylinder head 1 to the lift and heat it in a water bath.
16. Using liquid nitrogen, cool the new guide bushing 2 (figure 2.35).
Figure 2.35. Using liquid nitrogen, cool the new guide bushing 2.
Installation
17. Using punch 8, drive in the new guide bushing until it stops (figure 2.36).
Figure 2.36. Using punch 8, drive in the new guide bushing until it stops.
Examination
18. Check the guide bush diameter using tool 9 (figure 2.37).
Figure 2.37. Check the guide bush diameter using tool 9.
19. Install the reamer cutter and ream the diameter in the directions indicated by the arrows (figure 2.38). Never rotate the reamer in the opposite direction. The dimensions of the valve guide bushing are given in Table 2.4.
Figure 2.38. Install the reamer and ream the diameter in the directions indicated by the arrows.
Table 2.4. Valve guide bushing dimensions
| Parameters | Engines 602.984/985 | |
| Outer diameter of valve guide bushing D, mm | 1st rem size (color - red) | 14.245-14.256 |
| 2nd rem size (color - white) | 14.445-14.456 | |
| Main hole in cylinder head, mm | 1st rem size (color - red) | 14.200-14.211 |
| 2nd rem size (color - white) | 14 400-14.411 | |
| Inner diameter A of the guide bushing, mm | inlet valve | 8.000-8.030 |
| exhaust valve | 9.000-9.050 | |
| Overlap in cylinder head, mm | 0.029-0.051 | |
| Length of guide bushing L, mm | inlet valve | 39.5 |
| exhaust valve | 37.3 | |