Service of the Infiniti QX4 since 1996 of release
1. Introduction
2. Maintenance instruction
3. Routine maintenance
4. Engine
4.1. Specifications
4.2. Check of compression pressure in cylinders
4.3. Diagnostics of a condition of the engine with use of the vacuum gage
4.4. Removal and installation of the engine
4.5. Removal and installation of the inlet pipeline
4.6. Replacement of a belt of the GRM drive
4.7. Removal, check of a state and installation of a head of cylinders
4.8. Replacement of a forward epiploon of a bent shaft
4.9. Removal, check of a state and installation of components of the valvate mechanism
4.10. Replacement of epiploons of camshafts
4.11. Replacement of a back epiploon of a bent shaft
4.12. Removal and installation of the pallet of a case
4.13. Removal, service and installation of the oil pump
4.14. Alternative versions of schemes of recovery repair of the engine
4.15. An order of dismantling of the engine by preparation it to capital repairs
4.16. Dismantling and check of a condition of a head of cylinders and components of the valvate mechanism
4.17. Recommendations about service of valves
4.18. Assembly of a head of cylinders
4.19. Removal of conrod and piston assemblies
4.20. Removal of a bent shaft
4.21. Cleaning of the block of the engine
4.22. Check of a condition of the block of the engine
4.23. Honingovaniye of mirrors of cylinders
4.24. Check of a condition of components of conrod and piston group
4.25. Check of a condition of a bent shaft
4.26. Check of a state and selection of inserts of radical and conrod bearings of a bent shaft
4.27. Engine assembly order
4.28. Installation of piston rings
4.29. Installation of a bent shaft and check of working gaps of radical bearings
4.30. Installation of conrod and piston assemblies and check of size of working gaps in conrod bearings of a bent shaft
4.31. Trial start and a running in of the engine after capital repairs
5. Cooling system and heating
6. Feed and control systems
7. Systems of start and charge
8. Transmission line
9. Brake system
10. Suspension bracket and steering
11. Body
12. 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 of the valvate mechanism


Design of a head of cylinders

 

During dismantle of components try to fix their adjusting provisions.


Dismantling of a head of cylinders

The new or restored head of cylinders can always be ordered in a workshop of car service or in a warehouse branded HUNDRED Infinitis. In view of need of use during dismantling and check of a condition of a head of some special tools, authors of this manual consider, than to be got involved what to the amateur mechanic more simply and cheaper will be to get a replaceable head in rather complex recovery repair of worn-out.

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

 PERFORMANCE ORDER

  1. By means of the special tool squeeze springs of the first valve and take from a flute on a core crackers of the cutting lock of a plate. Carefully 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 of valvate springs it is convenient to use nippers or a small magnet.
  1. Put the removed components of valvate assemblies in accurately numbered separate plastic bags (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 a maslootrazhatelny cap from the directing plug. If there is a jamming of the valve in the directing plug, push it back in a head and an oselok or a file with small tooth accurately smooth out edges of a flute under installation of crackers.
  1. Working in a similar manner, remove the remained valvate assemblies. Put the removed components of each of valves in the separate, equipped with the corresponding label package — at assembly each detail has to be established strictly on the former place.
  2. After all components of the valvate mechanism are taken and put in an organized order, it is possible to start performing procedures of cleaning and check of a condition of a head (at full-scale recovery repair of the engine before finish its dismantling).


Cleaning

Careful cleaning of a head of cylinders and components of the valvate mechanism with the subsequent detailed check of their state will help to determine the approximate volume of the forthcoming recovery work.

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


 PERFORMANCE ORDER

  1. Scratch out all traces of material of old laying and sealant from the interfaced surfaces of a head of cylinders, the inlet pipeline and a final collector — try not to damage surfaces. Application of a special razmyagchitel which should impregnate previously stuck deposits will significantly facilitate work.
  2. Remove all traces of a scum from walls of water channels.
  3. Rigid wire brush carefully clean all available cavities and openings. At strong pollution of canals the clearing of a head should be charged to experts.
  4. "Banish" the tap suitable by the size each of bolted openings, having removed corrosion products, traces of old sealant from a carving and having restored the damaged rounds. In the presence of access to a source of compressed air, blow openings, having removed from them shaving and small garbage.

When using 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 significantly the term of drying and will give a quality assurance of a clearing of badly available cavities and openings.

Different structures for removal of traces of a deposit significantly facilitating implementation of the procedure of cleaning can be got in many shops of automobile accessories. Remember that such means usually are chemically aggressive and have to be applied with observance of the appropriate measures of precaution — strictly adhere to instructions of the manufacturers who are usually given on the label of a container.

  1. Wash out solvent of a yoke of the drive of valves, then carefully dry them. Use of compressed air will significantly facilitate implementation of the procedure (do not forget to put on goggles). Wash out in solvent and carefully dry valvate springs, their plates and crackers of cutting locks. Try not to mix components.
  2. Scratch out the bulk of the valves of deposits created on surfaces, then a wire nozzle to the electric drill finally smooth out surfaces of cores and plates of valves — you watch that valves were not mixed.


Check of a state and service of components


Casting of a head

 PERFORMANCE ORDER

  1. Having used the tool for compression of valvate springs (J-39773), remove components of valvate assemblies.
  1. By means of a steel line and the probe of lezviyny type estimate the size of not planeness of the interfaced head surface — in case of need give casting to a pro-point.

The pro-point is allowed only in case height of a head does not go beyond the lower admissible bound (see Specifications).


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


Valvate springs

A.

B.

Valvate the free length, perpendicularity of a tortsovka and the developed effort are among the parameters which are subject to check (see Specifications).

A — Check of a tortsovka of a valvate spring (extreme admissible size S makes: 2.2 mm for external springs and 1.9 mm for internal)
B — Check of the effort developed by a valvate spring by means of a dynamometer press


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


Maslootrazhatelny caps — an installation order

 PERFORMANCE ORDER

  1. Establish a saddle of an internal spring, oil a new cap pure motive and by means of a suitable mandrel accurately put him on the directi