Jeep Grand Cherokee

1993-1999 of release

Repair and operation of the car



Jeep Grand Cherokee
+ Cars of the Jeep Grand Cherokee brand
+ Settings and routine maintenance
+ Line six-cylinder engine
+ V8 engine
- Procedures of the general and capital repairs of the engine
   General information
   Capital repairs of the engine - the general information
   Check of compression pressure in cylinders
   The diagnostic checks made by means of the vacuum gage
   Methods of removal of the engine and necessary precautionary measures
   Removal and installation of the engine
   Options of restoration of the engine
   Order of dismantling of the engine
   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 of the engine
   Honingovaniye of cylinders
   Check of a condition of conrod and piston assemblies
   Check of a condition of a bent shaft
   Check of a condition of radical and conrod bearings
   Engine assembly order after completion of its capital repairs
   Installation of a bent shaft and check of gaps of radical bearings
   Installation of piston rings
   Installation of conrod and piston assemblies and check of gaps in conrod bearings
   The first start of the engine after capital repairs
+ Cooling systems, heating and air conditioning
+ A power supply system and production of the fulfilled gases
+ System of electric equipment of the engine
+ Systems of decrease in toxicity of the fulfilled gases and engine management
+ Manual box of gear shifting
+ Automatic transmission
+ Transfer case
+ Coupling and transmission line
+ Brake system
+ Suspension bracket and steering
+ Body
+ System of onboard electric equipment
+ Governing bodies and methods of operation



Cleaning and check of a condition of a head of cylinders

Cleaning

 PERFORMANCE ORDER

  1. Carefully clear a head (i) of cylinders and components of the valvate mechanism, then make check of its state that will allow to determine the volume of necessary recovery work by the valvate mechanism during performance of capital repairs of the engine.

It must be kept in mind that if during operation of the car strong overheats of the engine took place, then the head of cylinders will be perhaps deformed (planeness of its interfaced surface is broken).

  1. Scratch out all traces of material of old laying and sealant from the interfaced surfaces of a head, the inlet pipeline and a final collector. Try not to damage at the same time a head. Special solvents which use allows to soften laying material are produced - ask in shops of automobile accessories.
  2. Remove all traces of a scum from cooling channels.
  3. Clean small openings by means of a special rigid brush - the brush.
  4. Banish all carving openings a tap of the corresponding size, having removed traces of corrosion and sealant and having restored the damaged rounds. In the presence of access to a source of compressed air blow openings, having removed shaving and small garbage from a bottom.

When using of compressed air surely put on goggles!

  1. Rigid brush clean carvings of basic bolts of yokes.
  2. Wash out a head solvent and carefully dry it. Use of compressed air will allow to reduce significantly process of drying of a head and will give a guarantee of a qualitative clearing of all channels, openings and remote cavities.

Useful when cleaning a head and components of the valvate mechanism will be a use of dekarboniziruyushchy structures. Remember that such structures are usually very aggressive and it is necessary to use them with extra care. Try to adhere strictly to instructions of the manufacturers enclosed on packing.

  1. Wash out yokes, their basic bolts, or spherical support, fixing nuts or bolts and bars of pushers in solvent, then carefully dry them (you remember need of installation of all components at assembly on the former places - try not to mix details during cleaning). Use of compressed air will help to reduce process of drying of components and will provide care of a purge of openings and channels.
  2. Wash out in solvent all valvate springs, their saddles, crackers, plates (or rotary support), then carefully dry them. You make cleaning of components of each of valves serially for the purpose of providing a guarantee of a possibility of their installation at assembly on the former places.
  3. Scratch out the thickest layers of deposits from surfaces of plates of valves, then absolutely smooth out valves (both plates and cores) by means of a wire nozzle on the electric drill. Again you watch to mixing components.

Check of a state

Before coming to conclusion about need of carrying out machining of components it is necessary to execute everything from the listed checks. Make the list of the components demanding especially attentive relation.

Head of cylinders

 PERFORMANCE ORDER

  1. Carefully check a head for existence of cracks, traces of leakages of a cooler and other damages. In case of detection of cracks the head should be replaced (in case of impossibility of its restoration - consult in a workshop of car service).
  2. By means of the planeness measuring instrument (an edge of a steel ruler) and the probe of lezviyny type estimate extent of deformation of the interfaced head surface. If not planeness exceeds value, admissible on Specifications, the head should be given to a pro-point in a workshop of car service.

If machining of heads of cylinders of the V8 engine is made, it is also necessary to subject to processing and flanges of the inlet pipeline.


  1. Check the interfaced surface of a head of cylinders for planeness violation, filling for this purpose an edge of the probe of the required thickness under an edge of the steel ruler (the planeness measuring instrument) attached to a surface (the probe thickness corresponding to the maximum admissible value of not planeness can be determined according to Specifications).
  1. Carefully survey saddles of valves in each of combustion chambers. In case of identification on them of cavities, cracks or progar, the head demands carrying out service of valves which performance lies outside qualification of the average amateur mechanic.
  2. Define a gap between cores of valves and walls of the directing plugs, having measured for this purpose the size of a cross side play of a core of the valve by means of the dial measuring instrument of plunger type fixed on a head. The valve has to be in the directing plug and at distance about 1,6 mm from the saddle. The measured value of size of a side play for definition of a gap has to be divided into two. If after performance of measurements there are any doubts in correctness of assessment of a condition of the directing plugs of valves, they have to be brought for more exact check in a workshop of car service (the cost of such check has to be insignificant). If the gap is excessive, the directing plugs are subject to replacement.
  1. For determination of size of a gap between a core of the valve and walls of the directing plug the dial measuring instrument of plunger type can be used (determine core side play size in the directions specified by shooters).

Valves

 PERFORMANCE ORDER

  1. Carefully check a working surface of a plate of each of valves for existence of signs of uneven wear, deformations, cracks, cavities and progar. Check cores of valves for existence of zadir, agnails and the wiped sites, check necks of cores for existence of cracks. Having rotated the valve, make sure of lack of signs of a bend of a core. Check a core end face for existence of cavities and signs of excessive wear. Existence of any of the listed defects speaks about need of carrying out service of the valvate mechanism for a workshop of car service.

Check each of valves for existence of signs of wear and damages to the specified points

1 — a core End face
2 — the Flute under installation of crackers of the cutting lock
3 — the Core (the least subject to wear a part)
4 — the Core (the most subject to wear of a part)
5 — the Working surface of a plate of the valve
6 — the Cylindrical part (corbel) of the forming plate surface of the valve
  1. Measure width (height) of a cylindrical part (corbel) of the forming plate surface of the valve. If width of a corbel any of valves lies below a limit, admissible on Specifications, the valve is subject to replacement without fail.
  1. Width of a cylindrical part (corbel) of a plate of each of valves has to meet requirements of Specifications (if the corbel is absent, the valve cannot be subject to further use).

Components of valves

 PERFORMANCE ORDER

  1. Check end faces of valvate springs for existence of cavities and signs of wear. Measure the free length of springs and compare results of measurements to requirements of Specifications to this Chapter. If any of springs is shorter than admissible value, then it is considered "sunk" and is not subject to further use. To recognize springs fit for the restored engine it is necessary to make check of effort of their compression for installation (in a workshop of car service by means of the special equipment).
  1. Measure the free length of each of valvate springs by means of a vernier or dial caliper.
  1. Establish each of springs on a flat surface and check quality of its tortsovka. All deformed or "sunk" springs are subject to replacement without fail. Installation of springs with the broken tortsovka leads to the accelerated wear of the directing plugs.
  1. Check a tortsovka of all valvate springs.
  1. Check plates of springs (or rotary support) and crackers for existence of cracks and signs of wear. All components which are in a doubtful state have to be replaced new in order to avoid development of defects during operation of the restored engine.

Components of yokes

 PERFORMANCE ORDER

  1. Check working surfaces of yokes (the field of contact with end faces of bars of pushers and cores of valves) for existence of cavities, attritions, zadir, roughnesses and signs of wear. Also examine contact surfaces of yokes and their spherical support. Check everyone their yokes with a bolt and a nut of its fastening for existence of cracks.
  2. Check end faces of bars of pushers for existence of protertost and traces of excessive wear. Take for a drive pushers on a flat surface (a large splinter of a windowpane) for identification of their bend.
  3. Check bolted openings on fastening of yokes in heads of cylinders for existence of damage of rounds of a carving.
  4. All damaged or excessively worn-out components are subject to replacement.
  5. If in the course of survey the bad general condition of the valvate mechanism and wear of its components over admissible limits are revealed that is the normal phenomenon in the engine demanding capital repairs, install components of the valvate mechanism back in a head and study recommendations about carrying out service of valves (Section Service of Valves).