2.7. Removal and installation of a cam-shaft

Cam-shaft and drive of valves of the 4-cylinder petrol engine
1. Covers of radical bearings
2. Nut, 20 N · m
3. The spline (working without inhaling)
4. Cam-shaft
5. Conical crackers of the valve
6. External and internal springs
valve
7. Valve guide. Repair execution with a fillet
8. Head of the block of cylinders
9. Sealing ring		 10. Guides of valves
11. Valves
12. Cap
13. Cap
14. Lower plate of a valve spring
15. Oil scraper cap
16. Top plate of a valve spring.
Designation: wide facet outside, facet inside
17. Hydraulic dish-shaped pusher

4-CYLINDER PETROL ENGINE

Removal

PERFORMANCE ORDER
1. To remove the top casing of a gear belt.
2. To uncover a head of the block of cylinders.
3. To install the crankshaft in the provision of VMT for 1 cylinder (see subsection 2.5.2).
Prevention

Not to change position of the crankshaft of the engine any more.
4. To weaken a gear belt and to remove from above from a cam-shaft cogwheel (see subsection 2.5.1).
5. To jam a cam-shaft in front a thorn. For this purpose to insert a suitable thorn or the strong screw-driver into an opening of a cogwheel of a cam-shaft and to rest against the upper edge of a head of the block of cylinders. To avoid damage of the condensing surface of a head of the block of cylinders, to enclose wooden laying. Strongly holding the screw-driver, to weaken a bolt of fastening of a cam-shaft. To unscrew and remove a cam-shaft cogwheel, to hammer in case of need with easy blows of the rubber hammer. To remove a spline from a cam-shaft.
6. To mark all covers of radical bearings. Four covers, from right to left, depending on the course of the movement to mark with figures from 1 to 4.
7. To uncover 1 and 3. Then to unscrew cross-wise alternately covers 2 and 4.
8. To take out a cam-shaft.
Prevention

If dish-shaped pushers are taken out, they should be marked in order that again it was possible to establish on former places. To put dish-shaped pushers the surface of sliding (displacing towards a cam-shaft) down.

Installation

PERFORMANCE ORDER
1. Before installation if necessary it is possible to check a cam-shaft beating industrially. Limit of wear: 0,01 mm.
2. If on the engine with a big run or noise in the drive of valves the former cam-shaft is established again, it is recommended to check an axial gap. Limit of wear: 0.15 mm. Measurement is taken at the removed dish-shaped pushers and the established first and last covers of radical bearings.
3. To establish a new sealing ring of a cam-shaft. Previously to oil lips and an outer edge of a sealing ring.
4. To make trial installation of covers of the bearing, paying attention to position of the centers. Covers have to be established so that openings of covers and a head of the block of cylinders coincided. At the same time to pay attention to tags.
5. If dish-shaped pushers were removed, to establish them on former places. To grease dish-shaped pushers with a thin butter layer and at installation not to warp.
Prevention

It is impossible to interchange the position of dish-shaped pushers!
6. To oil and establish a cam-shaft.
Prevention

At the same time cams of 1 cylinder have to be directed up. To establish covers of bearings according to tags. To pay attention to position of the centers.
7. To tighten covers 2 and 4 cross-wise the moment of 20 N · m.
8. To establish 1 and 3 covers and to tighten the moment 20 N · m.
9. To establish a cam-shaft spline. To establish a driving gear wheel and to tighten the moment 80 N · m, holding at the same time a cogwheel a thorn.
10. To put on a gear belt a cam-shaft cogwheel, paying attention to the correct provision of an intermediate shaft and a vibroquencher (see subsection 2.5.2).
11. To pull a gear belt (see subsection 2.5.1).
12. To establish new laying of a cover of a head of the block of cylinders, having carefully tightened cover bolts the moment of 10 N · m.
13. To establish a protection of a gear belt.
Prevention

If new dish-shaped pushers are established, the engine within about 30 minutes cannot be started, otherwise the valve will rest against pistons!