Service Infiniti QX4 since 1996 of release
1. Introduction
2. The maintenance instruction
3. Routine maintenance
4. The engine
4.1. Specifications
4.2. Check компрессионного pressure in cylinders
4.3. Diagnostics of a condition of the engine with vacuum gauge application
4.4. Removal and engine installation
4.5. Removal and installation of the inlet pipeline
4.6. Replacement of a belt of drive ГРМ
4.7. Removal, check of a condition and installation of a head of cylinders
4.8. Replacement of a forward epiploon of a cranked shaft
4.9. Removal, check of a condition and installation of components клапанного the mechanism
4.10. Replacement of epiploons of camshafts
4.11. Replacement of a back epiploon of a cranked shaft
4.12. Removal and pallet installation картера
4.13. Removal, service and installation of the oil pump
4.14. Alternative variants of schemes of regenerative repair of the engine
4.15. An order of dismantling of the engine by its preparation for major repairs
4.16. Dismantling and check of a condition of a head of cylinders and components клапанного the mechanism
4.17. Recommendations about service of valves
4.18. Assemblage of a head of cylinders
4.19. Removal of shatunno-piston assemblages
4.20. Removal of a cranked shaft
4.21. Cleaning of the block of the engine
4.22. Check of a condition of the block of the engine
4.23. Хонингование mirrors of cylinders
4.24. Check of a condition of components of shatunno-piston group
4.25. Check of a condition of a cranked shaft
4.26. Check of a condition and selection of loose leaves radical and шатунных bearings of a cranked shaft
4.27. An engine assembly order
4.28. Installation of piston rings
4.29. Installation of a cranked shaft and check of working backlashes of radical bearings
4.30. Installation of shatunno-piston assemblages and check of size of working backlashes in шатунных bearings of a cranked shaft
4.31. Trial start and обкатка the engine after major repairs
5. Cooling and heating systems
6. Power supply systems and managements
7. Start and charge systems
8. A transmissionnaja line
9. Brake system
10. A suspension bracket and a steering
11. A body
12. An electric equipment
 












4-16-razborka-i-proverka-sostoyaniya-golovki-cilindrov-i-komponentov-klapannogo-mekhanizma.html

4.16. Dismantling and check of a condition of a head of cylinders and components клапанного the mechanism


Design of a head of cylinders

 

During dismantle of components try to fix their adjusting positions.


Dismantling of a head of cylinders

The new or restored head of cylinders always can be ordered in a workshop of car-care centre or in a warehouse firm HUNDRED Infiniti. In view of necessity of use during dismantling and check of a condition of a head of some special tools, composers of the given Management consider that to the mechanic-fan will get easier and more cheaply a replaceable head, than to be got involved in difficult enough regenerative repair worn out.

Dismantling of a head of cylinders demands preliminary dismantle клапанного the mechanism (inlet and final valves with accompanying components). It is meant that коромысла with axes and camshafts are already taken from a head (Removal, check of a condition and installation of components клапанного the mechanism see).

 PERFORMANCE ORDER

  1. By means of the special tool compress springs of the first valve and take from a flute on a core crackers of the cutting lock of a plate. Cautiously release the tool and remove from the valve a plate of springs, springs and their saddle (depending on a complete set). For extraction of crackers of the cutting lock after compression клапанных springs it is convenient to take advantage of nippers or a small magnet.
  1. The removed components клапанных assemblages put in accurately numbered separate polyethylene packages (an inscription on a label: components of the inlet valve of the third cylinder).
  1. Further, take the valve from a head of cylinders and remove from the directing plug маслоотражательный a cap. If there is a valve jamming in the directing plug, push it back in a head and оселком or a file with a small tooth accurately smooth out flute edges under installation of crackers.
  1. Operating in a similar manner, remove remained клапанные assemblages. Put removed components of each of valves in the separate package equipped with a corresponding label, — at assemblage each detail should be established strictly on the former place.
  2. After all components клапанного the mechanism will be taken and combined in the organised order, it is possible to start performance of procedures of cleaning and check of a condition of a head (at full-scale regenerative repair of the engine before finish its dismantling).


Cleaning

Careful clearing of a head of cylinders and components клапанного the mechanism with the subsequent detailed check of their condition will help to define approximate volume of a forthcoming recovery work.

Strong overheats of the engine can lead to deformation of a head of cylinders and infringement of planeness of its interfaced surfaces (see more low).


 PERFORMANCE ORDER

  1. Scratch out from interfaced surfaces of a head of cylinders, the inlet pipeline and a final collector all traces of a material of an old lining and hermetic — try not to damage a surface. Will essentially facilitate work application special размягчителя to which should impregnate stuck adjournment preliminary.
  2. Remove from walls of water channels all traces of a scum.
  3. Rigid wire brush carefully clean all accessible cavities and apertures. At strong pollution of channels it is necessary to charge head procleaning to experts.
  4. "Banish" a tap approaching on the size each of болтовых apertures, having removed from a carving corrosion products, traces of old hermetic and having restored the damaged coils. In the presence of access to a source of compressed air, blow apertures, having removed from them a shaving and small dust.

At use of compressed air do not forget to put on goggles!

  1. Wire brush smooth out a carving of hairpins of fastening of the inlet pipeline and a final collector.
  2. Wash out a head solvent and carefully dry it. Use of compressed air will allow to reduce essentially term of drying and will give the quality assurance of procleaning of badly accessible cavities and apertures.

For removal of traces of the deposit, procedures of cleaning essentially facilitating performance, it is possible to get any structures in many shops of automobile accessories. Remember that such means usually are chemically aggressive and should be applied with observance of corresponding safety measures, — strictly adhere to instructions of the manufacturers usually resulted on a label of container.

  1. Wash out solvent коромысла a drive of valves, then carefully dry them. Use of compressed air will essentially facilitate procedure performance (do not forget to put on goggles). Wash out in solvent and carefully dry клапанные springs, their plates and crackers of cutting locks. Try not to mix components.
  2. Scratch out a great bulk of the valves of adjournment generated on surfaces, then a wire nozzle to an electrodrill definitively smooth out surfaces of cores and plates of valves — watch, that valves have not appeared are mixed.


Check of a condition and service of components


Head moulding

 PERFORMANCE ORDER

  1. Having taken advantage of the tool for compression клапанных springs (J-39773), remove components клапанных assemblages.
  1. By means of a steel ruler and щупа лезвийного type estimate size неплоскостности an interfaced surface of a head, — in case of need give moulding in проточку.

Проточка it is supposed only in case the height of a head will not fall outside the limits the bottom admissible border (Specifications see).


The total thickness of the ground off layer of interfaced surfaces of a head and the block should not exceed 0.20 mm!


Klapannye springs

A.

B.

The free length, perpendicularity concern number of parametres subject to check клапанных торцовки and developed effort (Specifications see).

A — Check торцовки клапанной springs (limiting admissible size S makes: 2.2 mm for external springs and 1.9 mm for internal)
B — Check developed клапанной an effort spring with the help динамометрического the press


External клапанные springs are established by the party with the reduced step of a carving to a head.


Maslootrazhatelnye caps — an installation order

 PERFORMANCE ORDER

  1. Establish a saddle of an internal spring, grease a new cap with pure impellent oil and by means of approaching send accurately plant it on directing plug of the valve.

    A — Landing маслоотражательного a cap on directing plug
    B — the landing Scheme маслоотражательного a cap on the directing plug

A.

B.


Directing plugs — replacement

 PERFORMANCE ORDER

  1. Heat up a head of cylinders to temperature 150—160С. The head should be warmed up in an oil bath.
  1. Then by means of a press or a hammer and выколотки squeeze out / beat out directing plugs of valves subject to replacement from a head of cylinders in I will shift combustion chambers. Having finished dismantle of plugs, allow to a head to cool down to a room temperature.
  1. Way расточки achieve reduction of internal diameters of landing nests of directing plugs in conformity with standard requirements. The repair sizes make: 11.175—11.196 mm for plugs of inlet valves and 12.175—12.196 mm for the final.
  1. Again heat up a head to temperature 150—160С and запрессуйте new directing plugs in a head on demanded depth, — basic parametre is the size выступания plugs over surfaces of saddles external клапанных springs (the rating value makes 13.2—13.4 mm).
  1. Way расточки achieve reduction of internal diameters of plugs in conformity with standard requirements (the repair sizes make: 7.000—7.018 mm for plugs of inlet valves and 8.000—8.011 for final), — track conformity to norms of landing backlashes in plugs of cores of valves (the subsection "Valves" see).


Saddles of valves — replacement


Under control parametres of saddles of inlet valves


Under control parametres of saddles of final valves

Replacement клапанных saddles should be made after performance of procedures of service of directing plugs.

Extraction of saddles is made by them протачивания before destruction, track, that the cutter has not passed a head wall through.

 PERFORMANCE ORDER

  1. Take saddles and chisel landing nests under the repair size (the repair size with excess 0.5: 44.500—44.516 for saddles of inlet valves and 37.500—37.516 mm for final — under control geometrical parametres of saddles of valves — see illustrations Under control parametres of saddles of inlet valves and Under control parametres of saddles of final valves).
  2. Warm up a head of cylinders to temperature 150—160С and запрессуйте repair saddles in reception nests, — track completeness of landing of saddles. By a countersink and polishing achieve reduction of width and size of a corner of working facets of saddles in conformity with standard requirements:

Angle of slope facets (alpha), degrees:

  • Saddles of inlet and final valves

45

Width of a facet, mm

  • Saddles of inlet valves

1.75

  • Saddles of final valves

1.70

  1. In summary make grinding in of valves with application of special abrasive pastes of various granularity.


Valves


Geometrical parametres of valves subject to measurement

D — Diameter of a plate
a — the Angle of slope of a working facet
Т — Width of a cylindrical part plates (corbel)

d — Diameter of a core
L — Full length


 PERFORMANCE ORDER

  1. Make check of the under control sizes of valves (geometrical parametres of valves Subject to measurement see an illustration). Compare results of measurement to requirements of Specifications. In case of need make replacement.

Performance проточки cores of valves, but no more than 0.2 mm is in case of need supposed.

  1. Measure size люфта acting on 30 mm from plugs of valves in a plane perpendicular to camshafts, — if the result of measurement exceeds 0.20 mm, check up landing backlashes of valves in directing plugs.
  1. The size of a landing backlash can be defined by measurement of diameters of cores of valves and internal diameters of corresponding directing plugs, or by valve landing in the plug and direct gauging with the help циферблатного a measuring instrument плунжерного type. Compare results of check to requirements of Specifications, in case of need make replacement of valves / of directing plugs.

    A — Measurement of size of a backlash of landing of the valve in the directing plug
    B — Calculation of size of a backlash of landing of the valve in the directing plug

A.

B.
  1. At installation track size выступания cores of valves.

    A — the Scheme of installation of the inlet valve
    B — the Scheme of installation of the final valve

A.

B.


Components of a drive of valves


Assemblages of axes коромысел

 PERFORMANCE ORDER

  1. Remove axis assemblage коромысел.
  1. Mark adjusting positions коромысел on an axis. Check up components on presence of deep scratches, задиров and signs of excessive deterioration.
  1. Remove коромысла and check up landing backlashes коромысел on axes. In case of need make corresponding replacements.

    A — Measurement of external diameter of an axis коромысел (the rating value makes: 17.979-18.000 mm)
    B — Measurement of diameter of a landing aperture коромысла (the rating value makes: 18.007—18.028 mm, size of a landing backlash: 0.007—0.049 mm)

A.

B.


Hydraulic pushers

 PERFORMANCE ORDER

  1. Check up landing nests of pushers in a head of cylinders on presence of deep scratches, задиров and signs of excessive deterioration.
 
  1. Measure external diameters of pushers and internal diameters of their landing nests and by subtraction of results of the first measurement from results of the second define size of landing backlashes. Compare results of calculations to requirements of Specifications, in case of need make replacement of components.

    A — Measurement of external diameter of a pusher (arrows the surfaces which condition should be checked up are shown); the rating value makes: 15.947—15.957 mm
    B — Measurement of diameter of a nest under pusher landing

A.

B.
  1. Having established pushers, check up serviceability of their condition in free position (without an emphasis in коромысло). For check firmly press a pusher a finger (size of a landing backlash: 0.043—0.066 mm). If the moving size by pressing exceeds 1 mm, means in a pusher air has got, — air removal occurs automatically after approximately 10 minutes of work of the engine without loading on turns 1000 in a minute. If after prorolling published клапанным the mechanism the noise background does not decrease, it is necessary to replace pushers (prorolling of new pushers is made in a similar manner).


On page back
4.15. An order of dismantling of the engine by its preparation for major repairs
On the following page
4.17. Recommendations about service of valves