Subaru Legacy/Outback

1999-2003 of release

Repair and car operation



Subaru Legasi, Autbek
+ Cars Subaru Legacy, Outback
+ The operation manual
+ Routine maintenance
- The engine
   Specifications
   Check компрессионного pressure in cylinders and tightness of the block
   Diagnostics of a condition of the engine with vacuum gauge application
   System of greasing of the engine - the general information
   + The procedures of the repair which has been not connected with extraction of the engine from the car, - four-cylinder engines
   + The procedures of the repair which has been not connected with extraction of the engine from the car, - six-cylinder engines
   + The general and major repairs of engines
+ Systems of cooling, heating
+ The power supply system and release
+ Engine electric equipment
+ Manual box and differential
+ Automatic transmission
+ Coupling
+ Brake system
+ Suspension bracket and steering
+ Body
+ Onboard electric equipment

The engine

The general information

The scheme of an arrangement of the basic components 4-cylinder оппозитного engine SOHC

1 — the Camshaft
2 — the Inlet valve
3 — the Block of cylinders
4 — the Rod
5 — the Spark plug
6 — the Cover of camshafts
7 — Cover ГРМ

8 — the Head of cylinders
9 — the Pallet картера
10 — the Final valve
11 — Koromyslo of a drive of the final valve
12 — the Axis коромысел a drive of the final valve
13 — the Axis коромысел a drive of the inlet valve
14 — Koromyslo of a drive of the inlet valve


Design of a head of cylinders 4-cylinder оппозитного engine SOHC

1 — the Inlet valve
2 — the Inlet channel
3 — turbulence Area
4 — the combustion Chamber

5 — the Final channel
6 — the Final valve
7 — the Spark plug


Design of camshafts 4-cylinder оппозитного engine SOHC

1 — Podshipnikovye of a neck
2 — Maslotoki

3 — Persistent flanges

Design of components of a head of cylinders 6-cylinder оппозитного engine DOHC

1 — Inlet port
2 — the Inlet valve
3 — the Final valve

4 — Final port
5 — the combustion Chamber


Design of camshafts 6-cylinder оппозитного engine DOHC

1 — Podshipnikovye of a neck
2 — Maslotoki
3 — Persistent flanges
4 — the Flange of the gauge of position of a camshaft (CMP)

a — the Right inlet camshaft
b — the Right final camshaft
c — the Left inlet camshaft
d — the Left final camshaft


In the given Chapter the device and procedures of service of engines of two types is described: with one (SOHC) or two (DOHC) camshafts of the top arrangement for each of heads of cylinders.

4-cylinder engines of 2.0 and 2.5 l

On models 2.0 and 2.5 l are established 4-cylinder оппозитные the petrol engines horizontally established in a forward part of the car. Given 4-taktnye engines with liquid cooling and one (on a head) a camshaft of the top arrangement (SOHC) are supplied 16-klapannym by the mechanism timing and made mainly of an aluminium alloy. Fuel moves in the engine a method of the distributed injection (MFIS).

The block of cylinders

The block of cylinders is made of an aluminium alloy by a moulding method under pressure and supplied by pig-iron sleeves of cylinders of the dry type, filled in in unit semiblocks.

The structure of the cast block of cylinders allows to provide effective heat removal and gives it high durability at rather small weight.

The cranked shaft is established in five radical bearings of the raised durability the fifth of which is persistent and limits size axial люфта a shaft.

 


Installation sites of radical bearings of a cranked shaft are developed in such a manner that sufficient rigidity is provided at a minimum level of a working noise background.

The oil pump is located on the centre in a forward part of the block of cylinders, the water pump of system of cooling – in a forward part of the left semiblock. In a back part of the right semiblock the oil separator catching containing in картерных gases an oil suspension is established.

Heads of cylinders

Heads of cylinders are made of an aluminium alloy by a moulding method under pressure.

The head of cylinders forms chambers of combustion of tent type with the central arrangement of spark plugs and four valves (two inlet and two final) on the cylinder. Inlet and final valves are located on the different parties of the cylinder.

The central placing of spark plugs in combustion chambers promotes the distribution of turbulences increasing efficiency of combustion of an air-fuel mix.

For the account оппозитного arrangements of inlet and final valves the cross-section-line scheme timing is realised.

The metal lining of a head of cylinders is generated from steel corrosion-proof sheets and has the three-layer design, different the raised heat resistance and providing reliability of hermetic sealing of a joint of interfaced surfaces for a long time.

The drive of camshafts of the left and right heads of cylinders is carried out by means of one gear belt which also is used for a drive of the water pump located in the left semiblock of the power unit. Tension adjustment газораспределительного a belt is made by an automatic regulator of a tension that excludes necessity of manual updatings.

The camshaft is kept in a head of cylinders on four necks.

Two persistent flanges limit size axial люфта each of camshafts.

In an axial part of shaft greasings providing giving and cooling of components ГРМ are provided маслотоки.

In коромысла a drive of valves the screw and a nut intended for updating клапанных of backlashes are built in.

6-cylinder engines of 3.0 l

L models 3.0 are equipped by the 6-cylinder petrol engine оппозитной the designs, horizontally established in a forward part of the car. Given 4-taktnye engines with liquid cooling and two (on a head) camshafts of the top arrangement (DOHC) are supplied 24-klapannym by the mechanism timing and made mainly of an aluminium alloy. Fuel, as well as on 4-cylinder engines, moves a method of the distributed injection (MFIS).

Level of the vibrations made оппозитными by 6-cylinder engines, appreciably more low, than at engines of a V-shaped design (V6). Besides, the similar design at high compactness allows to organise good dynamic balancing. Decrease in the noise background arising at work of the engine, is helped also by following constructive decisions:

· the Cranked shaft is established in seven radical bearings of the raised durability and has diameter of 64.0 mm that on 4 mm more than on the previous models;
· Chains of drive ГРМ are equipped by a hydraulic regulator of a tension and closed by a cover;
· the pallet Made of an aluminium alloy картера strengthens rigidity of a joint of the left and right semiblocks, giving that additional durability to the zones forming beds of radical bearings of a cranked shaft;
· the Engine is connected to transmission by more rigid 11-boltovym connection in comparison with used in the previous models 8-boltovym connection.

Application of a chain drive of camshafts not requiring service has allowed to reduce full length of the power unit.

One more distinctive feature used on models Subaru Legacy 6-cylinder оппозитных engines is low level of the maintenance in the fulfilled gases of toxic components.

The block of cylinders

The block of cylinders is made of an aluminium alloy by a moulding method under pressure, supplied by pig-iron sleeves of cylinders of dry type and differs in low weight and the raised compactness:

· the Length of the cylinder makes 98.4 mm that is much less than length of cylinders of 4-cylinder engines (113 mm);
· the Parity of the sizes of length of the cylinder and a piston stroke is chosen optimum from reasons of development of necessary capacity at the compact sizes of the power unit, components according to 89.2 mm and 80.0 mm (in comparison with 92 mm and 75 mm for 4-cylinder engines 2.0);
· the Block of cylinders consists of two semiblocks, in each of which is located on three cylinders. The efficiency of heat-removing ability provided with development and an openness of a surface of semiblocks, allows to refuse necessity of the organisation connecting cylinders охладительных channels.

Each of semiblocks is equipped by an independent cooling contour. Water shirts round sleeves of cylinders are opened from outside heads (the open scheme) that appreciably raises efficiency of cooling of components.

The cranked shaft is established in 7 radical bearings the seventh of which is persistent.

 

The special form of the top part of the pallet made of an aluminium alloy картера promotes suppression of considerable fluctuations of level of oil and, besides, forms a part of contours of greasing and cooling, and as the spiral chamber of the water pump and the thermostat chamber.

Heads of cylinders

Heads of cylinders are made of an aluminium alloy by a moulding method under pressure that provides high efficiency of a heat-conducting path at insignificant weight of a product.

The design located in a head газораспределительного mechanism DOHC corresponds to the scheme «four valves on the cylinder». The arrangement of inlet valves provides formation of a falling stream while final valves are connected with each other and form the uniform pass having oval section through passage. The combination of a tent design of chambers of combustion to the central arrangement of spark plugs and the organisation of a falling stream in inlet ports promotes formation of area of an effective turbulence in chambers of combustion of cylinders. Use of such scheme allows to achieve effective combustion of an air-fuel mix and, as consequence, increase of capacity developed by the engine at the low maintenance in the fulfilled gases of toxic components.

The cooling liquid circulates in a direction from a forward part of a head of cylinders of each semiblock to back that increases efficiency of a heat-conducting path.

Between a head of cylinders and the block of cylinders the metal lining is used.

The drive of the right and left camshafts is carried out by different chains while auxiliary units are resulted by individual pulleys by means of the general streaming belt (in engines of the previous models used two belts of a drive of auxiliary units).

The body of a camshaft having composit structure (for the first time in practice Subaru) is formed of a carbonaceous steel. The working ledges of cams made of a ceramic-metal alloy differ the raised wear resistance allowing considerably to increase height of lifting at insignificant массогабаритных characteristics of a product.

Each camshaft is established in four bearings. The neck of the forward bearing is equipped from both parties by the persistent flanges limiting size axial люфта of a shaft.

Greasing to bearings moves from central маслотока through apertures in вейках.

On the back end of the right inlet camshaft the flange which is used by gauge CMP at definition of an angle of rotation of a shaft is located.


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