Service of Nissan Sunny from 1991 to 1997 release in n-14 body.
1. Maintenance instruction
2. Maintenance
3. Engines
3.1. 1,4 and 1,6 liters petrol engine
3.2. 2,0 liters petrol engine
3.2.1. Types of repair of the engine without dismantle from the car
3.2.2. Dismantle and capital repairs of the engine
3.2.2.1. Capital repairs of the engine
3.2.2.2. Dismantle of the power unit
3.2.2.3. The power unit from the manual transmission
3.2.2.4. The power unit with automatic transmission
3.2.2.5. Head of the block of cylinders
3.2.2.6. Head of cylinders and valves
3.2.2.7. The piston assembled with a rod
3.2.2.8. Crankshaft
3.2.2.9. Block of cylinders and crankshaft
3.2.2.10. Conrod and piston group
3.2.2.11. Radical and conrod bearings
3.2.2.12. Piston rings
3.2.2.13. Launch of the engine after capital repairs
3.3. Diesel engine
4. Cooling system
5. System of heating and ventilation
6. Fuel and exhaust system
7. System of launch of the engine
8. Coupling
9. Transmissions
10. Half shafts
11. Brakes
12. Suspension brackets and steering
13. Body
14. Electric equipment
 







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3.2.2.6. Head of cylinders and valves

Careful cleaning of a head of the block of cylinders and details of the valvate mechanism with the subsequent check will allow to estimate amount of works on repair of valves and the mechanism of the drive of valves at capital repairs of the engine.


Prevention

If the engine often overheated, then most likely the head of cylinders could warp, carefully check existence of signs of deformation of a head.


Cleaning

PERFORMANCE ORDER
1. Remove from demountable surfaces of a head of the block with the block of cylinders which is soaking up and final collectors all remains of material of laying.
2. Scrape off a deposit from combustion chambers, clear all openings and channels of a deposit, then wash out a head of the block of cylinders solvent.
3. Scrape off massive deposits of a deposit from all sites of valves, by means of a brush with the electric drive remove a deposit from heads and cores of valves.

Check


Prevention

Before drawing a conclusion on need of regrinding of details for a workshop surely perform all checks described below than the procedure. Make the list of what requires especially close attention.


PERFORMANCE ORDER
Head of cylinders
1. Attentively examine a head, check existence of cracks, traces of penetration of cooling liquid and other damages. At detection of cracks replace a head of cylinders.
2. Check a deviation of a demountable surface of a head of cylinders from the plane by means of the probe and calibration whetstone. If the curvature of the demountable plane is revealed, then the head should be proshlifovat. If deformation of the demountable plane such is that head height after grinding will become less specified in subsection 3.2.1.1, then replace a head.
3. Check a condition of saddles of valves in each combustion chamber. In the presence of pitting (poles), cracks, traces of a progar repair of a head in a workshop of car service will be required. Insignificant defects can be removed with grinding in of the valve to a saddle on fine structure.
4. Check wear of the directing plugs. For this purpose insert the valve into the corresponding directing plug and shake here and there. Small, hardly notable side play is admissible. If a valve side play in the plug considerable, then measure diameter of the valve. If diameter of the valve considerably decreased owing to wear, then replace the valve. If diameter of a core of the valve meets standard, then it is necessary to replace the directing plug. It is the best of all to perform this work in a workshop of car service, or to charge to the qualified mechanic.
5. If the directing plugs change, then saddles of valves should be pereshlifovat (or to perezenkovat) only after a press fitting of new plugs.
Valves
6. Attentively examine a head of each valve, check existence of cracks, degrees of wear and traces of a burn-out. Check existence on cores of valves of zadir and the fillet formed owing to wear. Turn of the valve check its bend. Check development at end faces of cores of valves. At detection of any signs of wear and damages replace the valve.
7. If as a result of this check it becomes clear that a condition of the valve satisfactory, then measure diameter of the valve in several places. Noticeable distinction of diameters indicates wear of a core of the valve. At detection of noticeable distinction of diameters at least in two places replace the valve (or valves).
8. If a condition of valves satisfactory, then them it is necessary to grind in to saddles to provide the tight contact excluding break of gases. If on saddles there are only insignificant damages, or the saddle was exposed to regrinding, then grinding in can be executed on fine abrasive structure. The coarse pritirochny structure should be applied only in case of detection of traces of deep development or a strong burn-out of saddles. In this case the head of cylinders and valves should be handed over on check to the skilled expert to define whether it is necessary to perezenkovat saddles, or even to replace inserts of saddles (if are provided).
9. Grinding in of valves is carried out as follows. Put a head of cylinders on a plain surface that combustion chambers were turned up.
10. Apply a thin film of pritirochny paste (the corresponding dispersion) on a saddle facet and press a sucker of device for grinding in of valves to a valve head.
11. Carry out grinding in, turning adaptation on 180 ° in both parties. In the course of grinding in sometimes raise the valve, for uniform redistribution of abrasive material. Grinding in is significantly facilitated if under a head of the valve to enclose not really rigid spring.
12. Grinding in on rough abrasive structure, it is necessary to finish after formation of a monotonous opaque corbel on facets of the valve and a saddle, then wipe the valve and a saddle from the remains of paste and continue grinding in on fine structure. Grinding in is considered complete at education on facets of the valve and a saddle of a uniform continuous corbel of grayish color. Further grinding in is not allowed as because of excessive development of a saddle the subsequent its repair can become impossible.
13. After the end of grinding in of all valves remove the remains of abrasive material, having carefully washed out all details kerosene or solvent.
Details of the valvate mechanism
14. Check existence on springs of traces of a vykrashivaniye and damages. The manufacturer recommends to check springs of valves by measurement of force which causes compression of a spring to a certain length. Such technique is possible only when using the special equipment. Therefore, check of springs should be carried out in service of car service of the dealer. A rough inspection of a condition of a spring can be carried out by comparison of length of a spring in a free state with specified in subsection 3.2.1.1.
15. Put each spring on a flat surface and put a square nearby. Measure distance between a round of a spring and a square in the top part and compare to the size specified in subsection 3.2.1.1.
16. If at least one of springs is damaged, has the raised deviation from a vertical, or lost elasticity, then replace all springs in a set. In general at capital repairs of a spring of valves it is recommended to change irrespective of their state.
17. Oil scraper caps change irrespective of their state.


3.2.2.5. Head of the block of cylinders

3.2.2.7. The piston assembled with a rod