Citroen Xantia

since 1993 of release

Repair and car operation

�� : 6 �� !

The repair procedures which are not demanding extraction of the engine from the car - diesel engines

This part of Head Repair of the engine is devoted to procedures of repair of diesel engines of the XUD series, not connected with unit extraction from the car (in situ). If the engine is already removed and prepared for dismantling for the purpose of performance of the general major maintenance (see. Removal and major maintenance of the engine), all preparatory procedures which were mentioned below can be lowered.

Despite basic possibility of performance of in situ of repair of such components as shatunno-piston assemblies, it is necessary to remember that this sort of works are accompanied always by a set of additional procedures (without speaking about need of carrying out cleaning of components and маслотоков). In view of told, such works are classified as procedure of the general major maintenance of the engine and are considered in the section Removal and major maintenance of the engine where the detailed description of procedures of removal and installation of the power unit also is provided.

Diesel engines of the XUD series - the general description

Perfectly proved throughout rather long term well-known in the world modern diesel engines of the XUD series are used for a complete set of a wide range of models of cars of the Citroёn brand. XUD units belong to family of ryadny 4-cylinder diesel engines with the top arrangement of a camshaft (OHC) and are established cross-section in a forward part of the car. Assemblies transmission assembly fastens in the left part of the unit.

Zubchatoremenny transfer is used for a drive of a camshaft, the fuel pump of a high pressure (TNVD) and the oil pump. Under each of ekstsentrikovy cams of a camshaft the individual pusher through which the drive of valves of chambers of combustion is carried out is established. Installation of klapanny gaps is carried out by selection of the adjusting washers established between pushers and end faces of cores of valves. The camshaft rotates in three bearings which beds are pierced directly in a body of a head of cylinders.

The cranked shaft is planted in five radical bearings of sliding. Supervising axial люфт a shaft persistent washers are established from both parties of the second radical bearing.

Pistons carefully picked up for weight fasten on the top heads of rods by means of piston fingers with floating landing. For fixing fingers from both parties are equipped with lock rings.

The internal pressure in system of greasing is created by the oil pump put in action from the forward end of a cranked shaft by means of chain transfer. All models are completed with a maslookhladitel.

On a design equipped with turbo-supercharging system engines a little than differs from engines with usual absorption of air. The cranked shaft and shatunno-piston group are applied only strengthened. Besides, the special masloraspylitel providing supply of oil on the bottom surfaces of pistons for the purpose of more effective cooling of the last are used.

In the course of the description of many of procedures of maintenance there is a need for division of engines not only on their working volume, but also on an identification code. The three-value code of the engine is formed by two letters of the Latin alphabet and one figure (D9B) and beaten out on шильде, attached to a forward wall of the block of cylinders.

The list of the procedures, which performance does not demand engine extraction from the car

To number of the procedures which are not demanding extraction of the engine from the car, the following belongs:
   a) Removal and installation of a head of cylinders;
   b) Removal and installation of a gas-distributing belt and cogwheels;
   c) Removal and camshaft installation;
   d) Removal and installation of the pallet of a crater of the engine;
   e) Removal and installation of shatunno-piston assemblies; *
   f) Removal and installation of the oil pump;
   g) Replacement of support of the power unit;
   h) Removal, check of a condition and flywheel installation / driving disk.
* In practice originators of the real Management do not recommend to perform these works of in situ in view of extreme limitation of working space and complexity of maintenance of purity.