Jeep Grand Cherokee

1993-1999 of release

Repair and car operation

Jeep Grandee Cheroki
+ Jeep Grand Cherokee brand Cars
+ Settings and routine maintenance
+ Ryadny six-cylinder engine
+ V8 Engine
- Procedures of the general and major maintenance of the engine
   General information
   Major maintenance of the engine - the general information
   Check of kompressionny 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 engine installation
   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 shatunno-piston assemblies
   Removal of a cranked 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 shatunno-piston assemblies
   Check of a condition of a cranked shaft
   Check of a condition of radical and shatunny bearings
   Engine assembly order after completion of its major maintenance
   Installation of a cranked shaft and check of gaps of radical bearings
   Installation of piston rings
   Installation of shatunno-piston assemblies and check of gaps in shatunny bearings
   The first start of the engine after major maintenance
+ Systems of cooling, heating and air conditioning
+ the 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 operation receptions

Cleaning and check of a condition of a head of cylinders



  1. Carefully clear a head (and) cylinders and components of the klapanny mechanism, then make check of its (their) condition that will allow to determine volume of necessary recovery operations by the klapanny mechanism during performance of major maintenance of the engine.

It is necessary to mean that if during operation of the car strong overheats of the engine took place, the head of cylinders probably will appear is deformed (planeness of its interfaced surface) is broken.

  1. Scratch out all traces of a material of old laying and hermetic from interfaced surfaces of a head, the inlet pipeline and a final collector. Try not to damage thus a head. The special solvents which application allows to soften a laying material are issued - ask in shops of automobile accessories.
  2. Remove from okhladitelny channels all traces of a scum.
  3. Small openings clean by means of a special rigid brush - ершика.
  4. All carving openings banish a tap of the corresponding size, having removed corrosion and hermetic traces and having restored the damaged rounds. In the presence of access to a source of the compressed air blow openings, having removed from a bottom shaving and small garbage.

When using the 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. Application of the compressed air will allow to reduce essentially process of drying of a head and will give a guarantee of high-quality pro-cleaning of all channels, openings and remote cavities.

Useful when cleaning a head and components of the klapanny mechanism there will be an application of dekarboniziruyushchy structures. Remember that such structures are usually very aggressive and to use them follows 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 (remember need of installation of all components at assembly on the former places - try not to mix details during cleaning). Application of the 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 klapanny springs, their saddles, crackers, plates (or rotary support), then carefully dry them. Make cleaning of components of each of valves serially for the purpose of providing a guarantee of 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 an electrodrill. Again watch to mixing components.

Condition check

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

Head of cylinders


  1. Carefully check a head on existence of cracks, traces of leakages of a cooler and other damages. In case of detection of cracks it is necessary to replace a head (in case of impossibility of its restoration - consult in a car-care center workshop).
  2. By means of a planeness measuring instrument (an edge of a steel ruler) and щупа lezviyny type estimate extent of deformation of an interfaced surface of a head. If not planeness exceeds admissible value according to Specifications, it is necessary to give a head to a pro-point in a car-care center workshop.

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

  1. Check an interfaced surface of a head of cylinders on planeness violation, filling for this purpose an edge щупа the demanded thickness under an edge of the steel ruler enclosed to a surface (a planeness measuring instrument) (thickness щупа, corresponding the maximum admissible value of not planeness can determine by Specifications).
  1. Carefully survey saddles of valves in each of combustion chambers. In case of identification on them of cavities, cracks or прогаров, the head demands carrying out service of the valves which performance lies outside the limits of qualification of the average amateur mechanic.
  2. Define a gap between cores of valves and walls of directing plugs, having measured for this purpose size cross-section люфта a valve core by means of the tsiferblatny measuring instrument of plunzherny type fixed on a head. The valve should be in the directing plug and at distance about 1,6 mm from the saddle. The measured value of size люфта for definition of a gap should be divided into two. If after performance of measurements there are any doubts in correctness of an assessment of a condition of directing plugs of valves, they should be delivered for more exact check in a car-care center workshop (cost of such check should be insignificant). If the gap is excessive, 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 tsiferblatny measuring instrument of plunzherny type (define size люфта a core in the directions specified by shooters) can be used.



  1. Carefully check a working surface of a plate of each of valves on existence of signs of non-uniform wear, deformations, cracks, cavities and прогаров. Check cores of valves on existence задиров, agnails and the wiped sites, necks of cores check on existence of cracks. Повращав the valve, make sure of lack of signs of a bend of a core. Check a core end face on existence of cavities and signs of excessive wear. Existence of any of the listed defects speaks about need of carrying out service of the klapanny mechanism for a car-care center workshop.

Check each of valves on 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 part least subject to wear)
4 — the Core (the parts most subject to wear)
5 — the Working surface of a plate of the valve
6 — the Cylindrical part (corbel) of a forming surface of a plate of the valve
  1. Measure width (height) of a cylindrical part (corbel) of a forming surface of a plate of the valve. If the width of a corbel any of valves lies below an admissible limit according to Specifications, the valve is subject to replacement without fail.
  1. The width of a cylindrical part (corbel) of a plate of each of valves should meet requirements of Specifications (if the corbel is absent, the valve cannot be subject to further use).

Components of valves


  1. Check end faces of klapanny springs on existence of cavities and wear signs. Measure free length of springs and compare results of measurements to requirements of Specifications to this Chapter. If any of springs it appears more shortly than admissible value, it is considered "given" and to further use is not subject. To recognize springs suitable for installation on the restored engine it is necessary to make check of effort of their compression (in a car-care center workshop by means of the special equipment).
  1. Measure free length of each of klapanny springs by means of a noniusny or tsiferblatny calliper.
  1. Establish each of springs on a flat surface and check quality of its tortsovka. All deformed or "given" springs are subject to replacement without fail. Installation of springs with the broken tortsovka conducts to the accelerated wear of directing plugs.
  1. Check a tortsovka of all klapanny springs.
  1. Check plates of springs (or rotary support) and crackers on existence of cracks and wear signs. All components being in a doubtful condition should be replaced new in order to avoid development of defects during operation of the restored engine.

Components of yokes


  1. Check working surfaces of yokes (area of contact with end faces of bars of pushers and cores of valves) on existence of cavities, attritions, задиров, roughnesses and wear signs. Also examine contact surfaces of yokes and their spherical support. Check everyone their yokes with a bolt and a nut of its fastening on existence of cracks.
  2. Check end faces of bars of pushers on 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 boltovy openings on fastening of yokes in heads of cylinders on 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 klapanny mechanism and wear of its components over admissible limits that is the normal phenomenon in the engine demanding major maintenance are revealed, establish components of the klapanny mechanism back in a head and familiarize with recommendations about carrying out service of valves (Undressed Service of valves).