VW Sharan repair. Diesel engines: 1,9 l of TDI.
+ 1. Introduction
- 2. VR6 engine
+ 2.1. Cнятие and installation
+ 2.2. Dismantling and assembly
+ 2.3. Head of the block of cylinders and valves
+ 2.4. Pistons and rods
2.5. Block of cylinders
+ 2.6. Cranked shaft and radical bearings
+ 2.7. Drive of the mechanism of a gazoraspredeleniye
2.8. Intermediate shaft
2.9. Compression check in engine cylinders
+ 2.10. System of production of the fulfilled gases
+ 3. Two-liter engine (ADY)
+ 4. System of greasing of the engine
+ 5. Cooling system
+ 6. System of injection of fuel of the VR6 engine
+ 7. Simos system of injection of fuel of the 2,0-liter engine
+ 8. Ignition system
+ 9. Coupling
+ 10. Mechanical 5-step transmission
+ 11. Shaft of a drive of wheels
+ 12. Hydraulic booster of a steering
+ 13. Forward suspension bracket
+ 14. Back suspension bracket
+ 15. Brake system
+ 16. Electric equipment
+ 17. Diesel engine
+ 18. System of greasing of the diesel engine
+ 19. System of cooling of the diesel engine
+ 20. Power supply system of the diesel engine and turbokompressor
+ maintenance Card
+ Specifications and characteristics
Repair Sharan/Sharan Volkswagen>> VR6 Engine
In this section the 6-cylinder engine under the name VR6, having considerable differences from the usual design concept of Volkswagen or Audi engines is considered established for the first time in 1991 on the Volkswagen Passat car. The engine in Volkswagen firm received the name "AAA", but it is better known as VR6. Its six cylinders are located V-shapedly at an angle 15 ° unlike the traditional V-shaped engines having a corner 60 ° or 90 °. The VR6 engine became so compact that allowed to cover both numbers of cylinders with one general head, unlike the ordinary V-shaped engine. As a result the VR6 engine turned out less on length, than ryadny, and it is less on width, than the ordinary V-shaped 6-cylinder engine. On (fig. 15) three types of 6-cylinder engines are schematically represented, and it is visible, on the basis of what the VR6 engine was developed.
At such acute angle of an arrangement of cylinders (15 °) problems with non-uniform rotation of a cranked shaft of the VR6 engine do not arise, it works as exactly, as well as ryadny. The engine has two camshafts which operate twelve vertically located valves (on 2 on the cylinder). Both camshafts of the top arrangement are placed in an aluminum head of the block of cylinders. The camshaft 1, 3 and the 5th cylinders is established on four bearings, and a camshaft for 2, 4 and the 6th cylinders – on three bearings. The surface of a head of the block of cylinders in an installation site of sealing laying is ground. Chambers of combustion are made at an angle to correspond to a V-shaped design of the engine.
The shod cranked shaft rotates on seven radical bearings and is supplied with twelve counterbalances and one quencher of krutilny fluctuations that allows it to rotate without radial palpation. Necks of a cranked shaft for each number of cylinders are displaced by Shatunnye on 22 °. Rather long rods (164 mm) connect a cranked shaft to lungs on weight the pistons having two kompressionny piston rings and one maslootrazhatelny ring. At the majority of the engines developed in recent years by Volkswagen firm the drive of a camshaft is carried out by a gear belt. However in the VR6 engine the drive of two camshafts is carried out by one general dvukhryadny chain (fig. 16) which is actuated from the asterisk of an intermediate shaft connected by a single-row chain to a gear wheel of a cranked shaft.
Two natyazhitel with boots (unattended) provide a demanded tension of chains, and tarelchaty self-regulating hydraulic pushers actuate valves. The design of the driving mechanism allowed to make more compact a head of the block of cylinders.
The special attention when designing addressed on a supply of an air and fuel mix as in one head of the block of cylinders with gas mixture two numbers of cylinders should be provided. The engine was designed with a cross-section purge — inlet channels settle down on one, and final channels on other party, and gas mixture in it should get at the same time to 3 cylinders on each party of the engine, and inlet pipes should be equal length.
For the solution of this problem the case of an air inlet established on the top part of a head of the block of cylinders from which to each cylinder there is the separate inlet pipe. Three pipes go directly to cylinders in a forward part of the engine, and other three pipes pass over the engine and incorporate to cylinders on the back party of the engine. Each inlet pipe is supplied with a nozzle, and spark plugs are located on outer side of cylinders.
In spite of the fact that designers tried to make inlet pipes as far as it is probably equal on length, after all there is a difference in speed of compression at two ranks of cylinders. However this difference is nullified, thanks to system of injection of Motronic fuel made by Bosch firm which regulates an injection and ignition operating mode depending on load of the engine and conditions of its work. The electronic control unit (EBU) defines amount of fuel injected into cylinders and an exact advancing of ignition, thanks to information received in the form of electric signals from sensors, namely: data on temperature, situation and frequency of rotation of a cranked shaft, a consumption of air arriving in the engine, extents of compression, advancing coal. The system of injection of "Motronic" is supplied with the detonation sensor in each number of cylinders that allows EBU to coordinate precisely management of injection and ignition for cylinders in each row and respectively to synchronize the compression moments.
Today for «Volkswagen» is almost a commonplace to establish on the cars converter and the sensor of oxygen which provide feedback. The sensor traces concentration of oxygen in the fulfilled gases, and EBU on its signals supports such ratio air/fuel which provides the most effective work of converter. The general view of the VR6 engine is assembled presented on (fig. 17) .