General information and sizes of details. Nissan Almera (from 1995 to 1999 of release)
Nissan Almera service from 1995 to 2000 in N15 body
1. General information
2. The general requirements to car repairs
3. Operation and car maintenance
4. Petrol engines
4.1. Removal and installation of the power unit
4.2. Dismantling and engine assembly
4.3. Block of cylinders
4.4. Shatunno-porshnevaya group
4.5. Cranked shaft and flywheel
4.6. Gazoraspredeleniye mechanism
4.6.1. General information and sizes of details
4.7. Head of the block of cylinders of GA14DE and GA16DE engines
4.8. Head of the block of cylinders of the SR20DE engine
4.9. Cooling system
4.10. Greasing system
4.11. System of production of the fulfilled gases
4.12. Power supply system
4.13. Complex control system of the engine (KSUD)
5. Diesel engines
6. Transmission
7. Running gear
8. Steering
9. Brake system
10. Electric equipment
11. Body
12. Appendices
13. Electric equipment schemes
 







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4-6-1-obshhie-svedeniya-i-razmery-detalejj.html

4.6.1. General information and sizes of details

In engines the 16-klapanny mechanism of a gazoraspredeleniye with two located in a head of the block of cylinders camshafts is applied. The drive of shaft is carried out from a cranked shaft by two roller chains on the GA14DE and GA16DE engines, one roller chain on the SR20DE engine.
The head of the cylinder is cast from an aluminum alloy, has on four valves on the cylinder; chambers of combustion of a hemispherical form. In a head of the block of cylinders saddles and directing plugs of valves are pressed. Cases of bearings of camshafts are processed for a single whole with a head of the block of cylinders and have demountable covers. The correct provision of a head on the block of cylinders is fixed by two adjusting plugs.

Fig. 2.13. Details of the mechanism of a gazoraspredeleniye of GA14DE and GA16DE engines: 1 — a pulley of a cranked shaft; 2 — a boot of a natyazhitel; 3 — laying;
4 — a natyazhitel of a chain of a drive of an intermediate asterisk; 5 — an asterisk of an inlet camshaft; 6 — a natyazhitel of a chain of a drive of camshafts; 7 — an asterisk of a final camshaft; 8 — a chain of a drive of camshafts; 9 — a camshaft of inlet valves; 10 — a camshaft of final valves; 11 — an adjusting washer; 12 — a pusher;
13 — crackers; 14 — a plate of a spring; 15 — a spring; 16 — a maslootrazhatelny cap; 17 — a basic washer of a spring; 18 — the valve; 19 — an axis of an intermediate asterisk; 20 — an intermediate asterisk; 21 — an uspokoitel; 22 — the purpose of a drive of an intermediate asterisk; 23 — an asterisk of a cranked shaft; 24 — the plug of a drive of the oil pump; 25 — a forward cover of a drive of camshafts


Fig. 2.14. Details of a drive of the mechanism of a gazoraspredeleniye of the SR20DE engine: 1 — an asterisk of an inlet camshaft; 2 — a bolt of fastening of the top directing chain; 3 — camshafts; 4 — top directing to a chain; 5 — a sealing ring; 6 — the block of cylinders; 7 — an asterisk of a final camshaft; 8 — a bolt of fastening of an asterisk of a camshaft; 9 — a chain of a drive of camshafts; 10 — a lobby directing to a chain; 11 — an asterisk of a cranked shaft; 12 — a bolt of fastening of a forward directing chain; 13 — the plug of a drive of the oil pump; 14 — a bolt of fastening of a cover of a drive of camshafts; 15 — a pulley of a cranked shaft; 16 — a bolt of fastening of a pulley of a cranked shaft; 17 — a cover of a drive of camshafts; 18 — a pin bolt; 19 — laying; 20 — a sealing ring; 21 — a natyazhitel of a chain; 22 — a bolt and a nut of a natyazhitel of a chain; 23 — a boot of a natyazhitel


The mechanism of a gazoraspredeleniye treat: a head of the block of cylinders, camshafts, inlet and final valves, springs of valves with details their installations directing plugs of valves, hydraulic pushers or pushers with adjusting washers, levers, driving chains, asterisks, natyazhitel of driving chains (fig. 2.13 and 2.14).
The height of a head of the block of cylinders of GA engines is measured between a surface of interface to the block of cylinders and the basic plane of bolts of fastening of a head and makes 117,8 — 118,0 mm.
The height of a head of the block of cylinders of SR engines is measured between interfaced surfaces of a head and should make 136,9 — 137,1 mm.
Tolerance from planeness of a surface of interface to the block of cylinders no more than 0,1 mm. When grinding this surface removal of metal no more than 0,2 mm is allowed.
Pig-iron directing plugs of valves are pressed in a head of the block of cylinders. The tightness at a press fitting of plugs in a head of the block of cylinders makes 0,024 — 0,059 mm.
Diameter of openings in a head of the block of cylinders for a press fitting of directing plugs, mm:
new       9,475 — 9,534
repair       9,723 — 9,734
Gap between a core of the valve and the directing plug for inlet valves 0,02 — 0,05 mm, for final valves 0,04 — 0,07 mm.
Vystupaniye of directing plugs of valves 11,5 — 11,7 mm.
Steel saddles of valves are pressed in a head of the block of cylinders.
Diameter of openings in a head of the block of cylinders for a press fitting of repair saddles of valves, mm:
the inlet:
       the engine GA14DE 30,500 — 30,516
       the engine GA16DE 31,500 — 31,516
the final:
for all       engines 25,500 — 25,516
Dimensional characteristics of saddles of valves of GA engines are presented in tab. 2.5.

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
External 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 bottom facet
60 °
-


Laying of a head of the block of cylinders is executed from a synthetic material (without the content of asbestos), has a silicone plait on perimeter and a metal fringing
openings round cylinders. Laying is established by a mark of "TORAHS" towards a head of the block of cylinders.
On GA14DE and GA16DE engines the mechanical pushers of a cylindrical form moving in openings of a head of the block of cylinders are applied. On the top part of pushers there is a dredging for installation of an adjusting washer. External diameter of pushers 29,960 — 29,975 mm. Diameter of openings in a head of the block of cylinders 30,000 — 30,021 mm. A gap between a pusher and an opening wall in a head of the block of cylinders 0,025 — 0,061 mm.
On the SR20DE engine the hydraulic pushers providing bezzazorny operation of the mechanism of a gazoraspredeleniye are established. External diameter of hydropushers 16,980 — 16,993 mm. Diameter of openings in a head of the block of cylinders 17,00 — 17,02 mm. A gap between a pusher and an opening wall in a head of the block of cylinders 0,07 — 0,04 mm.
In each chamber of combustion four steel valves (two inlet and two final), given by camshafts through pushers are established. Dimensional characteristics of valves of GA engines are presented in tab. 2.6.

Table 2.6  Dimensional characteristics of valves of GA14DE and GA16DE engines
Engine
Inlet valves
Final valves
Total length of the valve, mm
GA14DE and GA16DE engines
92,0-92,5
92,37-92,87
SR20DE engine
101,19-101,6
102,11-102,5
Diameter of a core of the valve, mm
GA14DE and GA16DE engines
5,465-5,480
5,445-5,460
SR20DE engine
5,965-5,980
36,945-6,960
Diameter of a cylindrical part of a plate of the valve, mm
GA14DE engine
28,9-29,2
23,9-24,2
GA16DE engine
29,9-30,2
23,9-24,2
SR20DE engine
34,0-34,2
30,0-30,2
Corner of a working facet of the valve
All engines
45°15 '-45°45'
Minimum admissible thickness of a cylindrical part of a plate of the valve, mm
All engines
0,9-1,1


On directing plugs of valves напрессованы maslootrazhatelny caps. On each valve one spring identical to inlet and final valves is established.
Length of a spring in a free condition:
— GA14DE engines and       GA16DE 41,19 mm;
— engine       of SR20DE 49,36 mm.
The length of a spring under loading of 34,5 kg should be equal 25,26 mm.
The most admissible not coaxiality of rounds of springs:
— for GA14DE engines and       GA16DE 1,8 mm;
— for the engine       of SR20DE 2,2 mm.
Camshafts are made of cast iron, inlet shaft — five-basic, final — six-basic.
The height of cams of engines of camshafts makes:
— for the GA14DE engine: 39,38 — 39,57 mm;
— for the GA16DE engine: 39,38 — 39,57 mm for a shaft of inlet valves: 39,88 — 40,07 mm for a shaft of final valves;
— for the SR20DE engine: 28,408 — 38,598 mm for a shaft of inlet valves; 37,92 — 38,11 mm for a shaft of final valves.
The most admissible wear of cams of 0,2 mm.
Gaps in the mechanism of a drive of valves of GA engines on the hot / cold engine make, mm:
inlet valves 0,32 — 0,40/0,25 — 0,33;
final valves 0,37 — 0,45/0,32 — 0,40.
Diameter of basic necks of camshafts, mm:
GA14DE and GA16DE engines:
neck No. 1 (from a camshaft drive)       27,935 — 27,955
necks No. 2 — 5       23,935 — 23,955
       the engine SR20DE 27,935 — 27,955
Radial gap of camshafts, mm:
nominal       0,045 — 0,086
the most admissible       0,15
Axial gap of camshafts, mm:
GA14DE and GA16DE engines:
nominal       0,070 — 0,143
the most admissible       0,2
SR20DE engine:
nominal       0,055 — 0,139
the most admissible       0,2

Fig. 2.15. Marking of camshafts: 1 — a camshaft of inlet valves; 2 — a camshaft of final valves


On camshafts of inlet valves marking of "I", final valves — «Е» (fig. 2.15) is put.

Fig. 2.16. Order of installation and marking of covers of cases of bearings of camshafts: 1 — cover number; 2 — the arrow directed towards a drive of camshafts


Numbering of covers of camshafts is given on fig. 2.16.
Phases of a gazoraspredeleniye of GA engines are specified in tab. 2.7 without a gap between cams of camshafts and pushers.

Table 2.7  of the Phase of a gazoraspredeleniye of GA engines
Characteristic
Engine model
GA14DE
GA16DE
The beginning of opening of the inlet valve to VMT of a step of release, an advancing
0 °
0 °
Closing of the inlet valve after NMT of a step of compression, delay
34 °
34 °
The beginning of opening of the final valve to NMT of a working course, an advancing
38 °
42 °
Closing of the final valve to VMT of a step of release, an advancing
4 °
0 °


The drive of camshafts on GA engines is carried out from a cranked shaft by two chains. One chain having 80 links, rotates the intermediate asterisk, the second, having 54 links, transfers rotation of an intermediate asterisk to camshafts. Camshafts of the SR20DE engine are given by one roller chain. Chains stretch hydraulic natyazhitel.

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4.7. Head of the block of cylinders of GA14DE and GA16DE engines