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Disassembly, repair and assembly of the cylinder head of the engine
If you need a repair cylinder head of the engine mounted on the car, remove the head (see. "Replacing cylinder head gasket"). In most cases, repair of the cylinder head is lapped or valve replacement, grinding or replacement of the valve seats. In these faults, as a violation of tightness channels shirt cooling and warpage mating surface of the cylinder block, cylinder head replaced. You will need: the keys "10", "12", "13" candle key, a magnetic screwdriver (or tweezers), devices for compressing the valve springs and remove the valve stem seals. 4. specially adapted for removing and installing valve springs compress the valve spring and remove crackers, holding the valve spring retainer. Remove tool, compress the spring. |
| Fig. 5.8. Cylinder head: 1 - tappet; 2 - rusk; 3 - valve spring plate; 4 - valve spring; 5 - the valve stem seal; 6 - bearing washer valve spring; 7 - the exhaust valve; 8 - inlet valve
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5. Remove the valve spring plate 3 (Fig. 5.8), 4 valve spring thrust washer 6 and the valve spring, then remove the valve. |
6. Similarly remove the remaining valves of the cylinder head. |
7. The special tool, remove the valve seals valve. |
8. Carefully clean the valve plate with a wire brush. |
| Fig. 5.9. Designated check valve: A - end of the stem; B - the contact point of the stem from the bottom edge of the valve guide; S - thickness of the valve disc
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9. Check all valves for wear, damage and deformation of the rod at the contact point with the bottom edge of the valve guide (Fig. 5.9). And if at the end of the valve stem has signs of wear, replace the valve. |
10. Replace the valve if the valve with a plate thickness of less than the limit. |
NOTE The nominal value of the thickness of the plate: - Intake valve - 1.0 mm; - Exhaust valve - 1.0 mm. |
| 11. Check the length and elasticity of the valve springs. If they exceed the maximum permissible value, replace spring. |
NOTE Nominal value of the length of the valve spring in the unloaded condition - 39.0 mm, the maximum allowable - 38.8 mm. |
12. gon check the deviation of each spring from the rectangular shape. If the deviation exceeds the limit, replace the spring. |
NOTE The deviation from the rectangular shape should be no more than 1,5 ?�. |
13. Remove the resinous sediments on the upper surface of the head and of the inlet channel. These deposits can be softened and rinse with kerosene or diesel toplivom.14. Clean carbon deposits from the combustion chamber and the exhaust ports. Remove carbon deposits round metal brush installed in the chuck of an electric. |
HELPFUL HINTS Pre-soak soot kerosene. Be careful: Avoid breathing dust generated during cleaning of combustion chambers. To prevent dust periodically moisten with kerosene soot. |
15. Check valve seat for the presence of heat and full contact with the beveled working valve. If necessary, repair or replace the seat. |
NOTE Replace or repair the valve seats should be in the service station, equipped with special equipment. |
16. Clean the inside surface of the valve guides a thin cylindrical copper wire brush clamped in the chuck of an electric. |
17. Remove the contact surface of the head to the cylinder block burnt remains of the gasket. |
18. Determine the valve guide wear by measuring the internal diameter of the sleeve hole and the diameter of the valve stem; the difference between these values determines the gap. If the clearance exceeds the limit, replace the valve guide to repair (larger). |
NOTE The nominal gap between the rod and the guide bush: - Inlet valve - 0,020-0,050 mm; - Exhaust valve - 0,050-0,085 mm. |
NOTE Replace valve guides should be in the service station, equipped with special equipment. |
19. After cleaning, check the cylinder head, to prevent it from operating with damaged threaded holes, cracks (especially between the valve seats and exhaust ducts), corrosion, inclusions of foreign materials, shells and fistulas. |
A WARNING It is forbidden to brew cracks shells and fistulas. Replace defective head. |
20. Test with a metal ruler, fixed to the edge, and the flatness of the probe head contact surface to the block in the longitudinal and transverse directions as well as diagonals. If the gap between the edge line and the head surface exceeds 0.1 mm, replace head. |
21. Clean the gasket from the remnants of soot and flange surfaces of the head for the installation of an inlet pipe and katkollektora. |
22. Check for deformation of the flanges to the inlet tube and katkollektora deformed head replace. |
23. Repair the damaged threaded holes sweep thread taps or installation repair sleeve (vvertysha). |
| | 24. Check the condition of the valve seats. On working facets of saddles should not be signs of wear, pitting, corrosion, etc. Saddle valves can be replaced in a specialized workshop. Minor damage (small risks, scratches, etc.) Can be derived lapping valve (see. "Lapping valves"). | 25. More significant valve seats eliminate defects by grinding. Saddles must be sanded by a specialist workshop, as it requires special tools and equipment. If major defects saddles eliminate grinding persists, replace the seat. |
26. Remove carbon from valves and inspect them. Deformation of the valve stem, and a crack on his plate is not allowed. If damaged, replace the valve. Make sure there are not too worn out and damaged working facet. Allowed grinding working facet of valves (in the repair shops have the appropriate equipment). After grinding the thickness of the cylindrical part of the plates must be at least 0,97-1,57 mm for the inlet and exhaust valves. Minor scratches on the risks and chamfer can be displayed to the lapping of the valve seat (see. "Lapping valves"). |
A WARNING In order for valve stems are not formed risks do not clean their wire brush and metal scraper. |
27. Check the concentricity of the location of the valve disc and seat: put on a facet of the valve head a thin layer of paint (for example, Prussian Blue), insert it into the guide sleeve and lightly pressed against the seat, turn. On the trail of paint on the facet of a saddle can judge the concentric valve and seat. |
28. Check the grooves of the valve stem by crackers. If you find traces of chipping the edges of grooves of the cylindrical part and wear, replace the valve. |
29. Replace the valve seals, regardless of their status. |
30. Check the condition of the spring plates. Replace the dish with a considerable wear grooves for supporting the spring. |
31. Install all removed parts and components of the cylinder head in the reverse order of removal. |
32. Always replace with new cylinder head gaskets, intake pipe (receiver), and the exhaust manifold as taken with the engine not even look damaged pads can be highly compacted and ensure tightness of the seal. |
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