Service of Nissan Almera from 1995 to 2000 in N15 body
1. General information
2. General requirements to car repairs
3. Operation and maintenance of the car
4. Petrol engines
4.1. Removal and installation of the power unit
4.2. Dismantling and assembly of the engine
4.3. Block of cylinders
4.4. Conrod and piston group
4.5. Bent shaft and flywheel
4.6. Gas distribution mechanism
4.7. Head of the block of cylinders of GA14DE and GA16DE engines
4.7.1. Removal of a head of the block of cylinders
4.7.2. Installation of a head of the block of cylinders
4.7.3. Dismantling, check of technical condition, repair and assembly of a head of the block tsilindrova
4.7.4. Check and adjustment of gaps in the mechanism of the drive of valves
4.8. Head of the block of cylinders of the SR20DE engine
4.9. Cooling system
4.10. Lubrication system
4.11. System of production of the fulfilled gases
4.12. Power supply system
4.13. Complex Control System of the Engine (CCSE)
5. Diesel engines
6. Transmission
7. Running gear
8. Steering
9. Brake system
10. Electric equipment
11. Body
12. Appendices
13. Schemes of electric equipment
 





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4.7.3. Dismantling, check of technical condition, repair and assembly of a head of the block tsilindrova

Establish a head of the block of cylinders on a support. Apply tags on the removed details that correctly to establish them at assembly. Remove the inlet pipeline together with the fuel highway. Disconnect the pipeline of system of recirculation of the fulfilled gases from a head. Disconnect a final collector, previously having removed from it the thermoisolating screen. Take out adjusting washers and pushers. Remove valves by means of the device for compression of springs like Facom U43LA and lay for each valve separately crackers, a plate springs, a basic washer. Clear all details. Remove maslootrazhayushchy caps from the directing plugs. To remove the laying remains from details from aluminum alloy, it is possible to use a shaber or other sharp tool. However act carefully as it can lead to damage of surfaces of interface. It is preferable to use chemical Loctite — Decaploc 88 solvent or Decapjoint to this purpose.
Repair of a head of the block of cylinders demands the special equipment therefore it is desirable to carry out it in repair shops.
Examine the removed details, be convinced of lack of cracks, chips, considerable wear of a working surface and other defects. Are instructed on check of technical condition of the main details of a head of the block of cylinders below.

The directing plugs of valves

Fig. 2.31. Installation of the directing plugs of valves: and = 11,5 — 11,7 mm


Are pressed in a head of the block of cylinders (fig. 2.31). Repair plugs with increase external and reduced internal by diameters are provided. Vypressovka of worn-out plugs is carried out by means of a press and a mandrel.
Previously warm a head in an oil bathtub up to the temperature of 110 — 120 °C. Then chisel openings under the plug of the repair size. You carry out a press fitting of plugs to a head also after its heating to the specified temperature then develop an internal opening of the pressed plug under diameter of a core of the valve.

Valves

Fig. 2.32. Geometrical sizes of the valve: Е — thickness of a cylindrical part of a plate of the valve; D — diameter of a plate of the valve; d — diameter of a core of the valve; L — the total length of the valve;
a — a corner of a working facet of the valve


The gap between a core of the valve and the directing plug should not exceed admissible size. As valves of the repair sizes are not provided, it is necessary to replace the valve and the plug in couple. Grind a head of the valve and grind in only within the sizes specified in tab. 2.6. After grinding of facets carefully clear a head of the block of cylinders and check tightness of valves. The geometrical sizes of the valve are specified fig. 2.32.

Saddles of valves

Fig. 2.33. Geometrical sizes of saddles of valves: And — inlet; B — final; D1 — the outer diameter of a working facet; D2 — the internal diameter of a working facet; L — width of a working facet; a — a corner of a working facet; b1 — a corner of the top facet; b2 — a corner of the lower facet


Are pressed in a head of the block of cylinders. Saddles can be ground within the sizes specified in tab. 2.5. You make replacement of saddles after heating of a head of the block of cylinders in an oil bathtub up to the temperature of 110 — 120 °C with use of a press and mandrel. After grinding of facets carefully clear a head of the block of cylinders and check tightness of saddles. The geometrical sizes of saddles are given in fig. 2.33.

Table 2.5 Dimensional characteristics of saddles of valves of GA14DE and GA16DE engines
Characteristic
Inlet valves
Final valves
Width of a working facet, mm
1,06-1,34
1,20-1,68
Outer diameter of a working facet, mm
29,5-29,7
23,5-23,7
Internal diameter of a working facet, mm
27,8-28,0
-
Corner of a working facet
45 °
-
Corner of the top facet
30 °
15 °
Corner of the lower facet
60 °
-

Maslootrazhatelny caps
Always are subject to replacement at repair of a head. Replace them after removal of basic washers of valves by means of a mandrel.

Springs of valves
Check a corner of a deviation of rounds of a spring from an axis. At a skalyvaniye of a protective varnish it is recommended to replace springs because of a possibility of a rupture of a spring at operation. Do not clear a spring with use of gasoline or trichlorethylene as these substances can dissolve a protective varnish.

Pushers
Check a condition of a surface and a gap between pushers and walls of their nests. Examine a surface of nests of pushers. In case of the wear exceeding admissible replace pushers or a head of the block of cylinders.

Surface of interface of a head to the block of cylinders
If the deviation from planeness of a surface of interface of a head of the block of cylinders to the block exceeds 0,1 mm and the camshaft freely rotates, carry out grinding of a head of the block of cylinders. Thickness of the removed layer of metal should not exceed 0,2 mm. Otherwise replace a head of the block of cylinders.

Camshafts and asterisks
Examine the surface of camshafts and their support, paying special attention to wear of cams and necks. Check their geometrical sizes. At a considerable deviation of the measured sizes from admissible replace a shaft or a head of the block of cylinders. Check a radial and axial beating of shaft and asterisks. Replace details at considerable wear.

Fig. 2.34. Details of a head of the block of cylinders:
1 — a stopper of an oil filling mouth;
2 — a cover of a head of the block of cylinders; 3 — laying of a cover of a head of the block of cylinders;
4 — a cover of the bearing of the camshaft of inlet valves; 5 — a cover of the bearing of the camshaft of final valves;
6 — a bolt of fastening of a head of the block of cylinders;
7 — a head of the block of cylinders; 8 — the directing valve plug; 9 — a forward cover of a head of the block of cylinders; 10 — laying of a head of the block of cylinders; 11 — a valve saddle


At assembly of a head of the block of cylinders it is necessary to oil engine the recommended quality all adjoining details. During the work be guided by fig. 2.34.
Clear a head of the block of cylinders and all removed details. Blow channels of a head of the block of cylinders, having paid special attention to channels of lubricant of camshafts. When using of earlier removed valves install them on the places.
Carry out assembly of the valvate mechanism in such sequence. Insert the valve into the directing plug, put on the basic washer directing the plug, a napressuyta a new oil scraper cap, put a spring and a plate of a spring. Squeeze adaptation a spring and establish crackers. Put a head of the block of cylinders on an edge and, slightly tapping with the copper or bronze hammer at the edges of cores of valves, achieve the correct landing of crackers. Establish on the places pushers with adjusting washers. Establish the final collector with new laying then thermoisolating the screen. Install the inlet pipeline with new laying. Install the HORN pipeline between the inlet pipeline and a final collector.

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4.7.2. Installation of a head of the block of cylinders
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4.7.4. Check and adjustment of gaps in the mechanism of the drive of valves