Nissan Maxima QX

since 1993 release

Repair and operation of the car


Nissan Maxima QX
+ Cars of the Nissan Maxima brand
+ Maintenance instruction
+ Settings and routine maintenance
- Engine
   + SOHC engines
   + DOHC engines
   - General capital repairs of the engine
      General information
      Check of pressure of oil
      Check of compression pressure in cylinders
      Diagnostics of a condition of the engine with use of the vacuum gage
      Alternative versions of schemes of recovery repair of the engine
      Removal of the power unit from the car - preparation and precautionary measures
      Removal and installation of the engine
      Order of dismantling of the engine by preparation it to capital repairs
      Dismantling of a head of cylinders
      Cleaning and check of a condition of a head of cylinders
      Service of valves
      Assembly of a head of cylinders
      Removal of conrod and piston assemblies
      Removal of a bent shaft
      Cleaning of the block of the engine
      Check of a condition of the block
      Honingovaniye of mirrors of cylinders
      Check of a condition of components of conrod and piston group
      Check of a condition of a bent shaft
      Check of a state and selection of inserts of radical and conrod bearings of a bent shaft
      Check of a condition of camshafts, pushers of valves and bearings
      Engine assembly order
      Installation of piston rings
      Installation of a bent shaft and check of working gaps of radical bearings
      Installation of a back epiploon of a bent shaft
      Installation of conrod and piston assemblies and check of size of working gaps in conrod bearings of a bent shaft
      Trial start and running in of the engine after capital repairs
+ Cooling systems, heating
+ Power supply system and release
+ Engine electric equipment
+ Control systems of the engine
+ Transmission
+ Coupling and power shafts
+ Brake system
+ Suspension bracket and steering
+ Body
+ Onboard electric equipment

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 company service center of the company manufacturer of the car. In view of need of use during dismantling and check of a condition of a head of some special tools, authors of the present 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.


 PERFORMANCE ORDER

1. Dismantling of a head of cylinders demands preliminary dismantle of elements of the valvate mechanism (inlet and final valves with the accompanying components). On SOHC engines remove assemblies of yokes with axes. Take from heads camshafts with pushers of valves (the description of procedures of check of a condition of components see in the Section Check of a Condition of Camshafts, pushers of valves and bearings).

On SOHC engines the removed pushers in order to avoid hit in them air traffic jams should not turn over on one side (see the Part SOHC Engines of the present Chapter). Alternatively it is necessary to put the removed pushers in the container filled with oil.

2. Prepare a set of accurately marked polyethylene bags for organized warehousing of the removed components of the valvate mechanism.

3. 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 of springs. Carefully release the tool and remove from the valve a plate of springs, springs and their saddle (depending on a complete set).

Try not to damage internal walls of a nest under landing of a pusher when tightening valvate springs.

4. 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 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.

5. Working in a similar manner, dismantle 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.
6. 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 the engine (at full-scale recovery repair before finish dismantling of the unit).