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
- Systems of cooling, heating
   + System of cooling of the engine
   + Heating/ventilation/air conditioning systems
+ 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

Systems of cooling, heating

The general information and safety measures

System of cooling of the engine

The scheme of circulation of a cooling liquid on an example of the 6-cylinder engine

1 — the Water pump
2 — Masloohladitel
3 — the Right head of cylinders
4 — the Block of cylinders

5 — the Left head of cylinders
6 — the throttle Case
7 — the Thermostat

The scheme of the organisation of heating/ventilation of salon

1 — Forward дефлектор an air line blowing a windscreen
2 — Lateral deflectors an air line blowing a windscreen
3 — Deflektory of the central air line of the panel of devices
4 — Deflektory of lateral air lines of the panel of devices
5 — Lobbies deflectors the bottom air line
6 — Back deflectors the bottom air line
7 — Fresh air
8 — air circulation Streams
9 — Ventilating заслонка

10 — Zaslonka of the bottom air line
11 — Zaslonka of an air line blowing a windscreen
12 — Mixing заслонка
13 — Inlet заслонки
14 — the heater Heat exchanger
15 — the Evaporator (models with К/В)
16 — the heater Fan
17 — the Filter (an additional complete set)

The servo-driver of management of functioning regime заслонок

1 — Having blown in a windscreen
2 — Having blown in salon glass/heating

3 — salon Heating
4 — salon Ventilation/heating

All models of cars considered in the present Management are equipped by system of cooling of the engine working at superfluous pressure with thermostatic management of circulation of a working liquid. The water pump роторного type is fixed on the left semiblock of the engine (model 2.0 and 2.5), or placed in a casing, образуемый with deepenings in a back cover of drive ГРМ and the top section of the pallet картера (models 3.0) and provides prorolling of a cooling liquid through охладительный a path of the power unit (see Has undressed the Water pump - the general information). The drive of the water pump is carried out from газораспределительного a belt/chain. The liquid stream washes areas of an arrangement of each of cylinders in the block, laid in moulding of semiblocks and heads of cylinders охладительные channels provide intensive cooling of inlet and final ports, areas of installation of spark plugs and directing plugs of final valves. The system of cooling from the moment of engine start passes through three modes of functioning: at the first stage while that пература a cooling liquid has not risen above 76 С, the thermostat remains closed and the liquid circulates on a small circle from which working contour the radiator is excluded that provides a fast warming up of the engine; at temperature 76 80 С the thermostat opens and the circulation contour joins a radiator; on reaching temperature of a cooling liquid of value 95С (4-cylinder engines)/91S (6-cylinder engines) ECM, being guided by indications of the gauge of temperature of a cooling liquid (ECT), gives out the command on fan activation (ов) the cooling systems, forced which () an additional air stream appreciably is raised by efficiency of functioning of the heat exchanger of a radiator.

The voskozapolnennyj thermostat is built in an inlet branch pipe of the water pump and supervises working temperature of the engine in the course of its warming up. First minutes after start of the cold engine the thermostat remains closed, preventing thereby circulation of a cooling liquid through a radiator. In process of approach of temperature of the engine to normal working value, the thermostat valve gradually opens, connecting to a contour of cooling a radiator providing the maximum intensity of a heat-conducting path from a working body (cooling liquid).


The cooling system has a tight design and is densely closed by a cover of the radiator, capable to maintain superfluous pressure that provides increase of a boiling point of a cooling liquid and, accordingly, efficiency of a heat-conducting path through a radiator. At excess by internal pressure in system of some certain value, подпружиненная the plate of the radiator of a safety valve built in in a cover rises over the saddle, providing an overflowing of surplus of a cooling liquid on connecting (переливной) to a tube in a broad tank. In process of cooling of system the liquid automatically comes back from a tank in a radiator.

Доливание a cooling liquid in system it is made through a mouth of a broad tank which simultaneously acts also in a role of the receiver accumulating in superseded from radiator surplus of a liquid extending at a warming up.

In view of the listed features of a design, such system of cooling has received the name closed as in it any functional losses of a working body are excluded.

Heating/ventilation/air conditioning systems (HVAC)

System of heating/ventilation of salon

The basic components of system of heating/ventilation of salon are placed in fixed under the panel of devices a box-shaped casing of a heater the electric fan and the heat exchanger, and also system of air lines of distribution of an air stream. Разогретая in the engine the cooling liquid circulates through the heater heat exchanger, giving the to air warmly filling a casing, at fan inclusion крыльчатка air submitted to salon through the heat exchanger starts to banish the last, providing its intensive warming up. Fan activation is possible only at the included ignition, the choice of a high-speed mode of the fan is provided with the special resistive assemblage connected to operating switch drive the electromotor.


The heat exchanger by means of rubber hoses is connected to system of cooling of the engine. Assemblage of management by functioning of a heater/conditioner of air is built in in an average part of the panel of devices of the car and by means of change of positions corresponding заслонок allows to carry out adjustment of temperature and a choice of a direction of distribution of an air stream. The electromotor of a drive inlet заслонки is located in the top part of inlet section of assemblage of a heater and, depending on position of the switch of modes of circulation provides giving in salon of fresh air, or its circulation in volume of salon of the car. The management servo-driver regime заслонками is fixed on the left side of assemblage of a heater and on the signals arriving from operating switches, provides demanded moving corresponding заслонок.

As an additional complete set in a contour of system of heating/ventilation it can be established салонный the filter providing clearing of air submitted to salon from a dust. The filter is located directly behind the fan, ahead of the evaporator module.

1 — Filtering elements
2 — Evaporator K/V

Air central air (К/В)

The central air structure includes the condenser established ahead of a radiator close to the heat exchanger of a heater the evaporator, fixed on the block of the engine the compressor, and the filtering receiver-dehumidifier (accumulator) equipped редукционным with the valve of a high pressure. All components are connected among themselves by refrigerator lines. Circulating in a path of a central air the coolant leaves the compressor, is banished through the condenser, a receiver-dehumidifier and the evaporator, then again comes back in the compressor, the expense of a coolant arriving in the evaporator is regulated by the broad valve built in the evaporator.


The evaporator temperature is constantly supported at some set level at the expense of management of compressor activation. When the evaporator temperature falls below a preset value, the special thermosensitive actuation mechanism makes a compressor stop, at evaporator rise in temperature the same device starts again the compressor.

For protection of working contour К/В against excessive increase or pressure drop the special gauge-switch on which signal compressor blocking also is made is provided.

The fan banishes air arriving in salon through the heat exchanger of the evaporator working in a mode, the return to a mode of functioning of a radiator. The coolant pumped over through the heat exchanger begins to boil and, evaporating, selects at air surplus of heat. The temperature in salon thus decreases to demanded comfortable value (for choice the operator). The compressor supports coolant circulation in system, pumping over разогретую a liquid through the condenser where it is cooled and arrives back in the evaporator.

Elements of management of functioning of a central air are a part of the same assemblage from which the choice of working parametres of systems of heating and ventilation is carried out.

Automatic central air of air (climate control)

On some models the centralised management of functioning of systems of heating, ventilation and air-conditioning by air (climate control system) is organised. At such complete set environmental conditions in car salon are supported automatically according to the installations entered by the user. Assemblage of management HVAC is located in the central part of the panel of devices of the car on a standard place where the control panel of systems of heating/ventilation and air-conditioning of models of a standard complete set usually is located.

Maintenance of the set temperature is carried out at the expense of the organisation in a control system of the climate control of a feedback with ECM through additional information gauges. Number of such gauges concern working on a principle термистора gauges of temperature of air inside and outside of the car and the sunlight gauge.


For air giving on a sensitive element of the gauge of temperature of air in car salon depression created by an air stream owing to what the gauge functions only at the included fan of a heater is used.

The gauge of temperature of external air is fixed on a rack of a radiator behind a decorative lattice of the last that provides good it having blown in a running stream. For the purpose of increase of thermal capacity the gauge case is made of plastic that reduces speed of reaction термистора on temperature change, thus, the gauge fixes only an average ambient temperature and is not capable to register its sharp changes.

The basis of a design of the gauge of a sunlight is made by the photo diode which is giving out on ECM electric, proportional intensity of a sunlight.

On the basis of the analysis of data ECM continuously arriving from information gauges operates functioning built in in mixing демпфер the servomotor, by means of draught connected with демпферным the valve. The potentiometer a part of the servomotor informs ECM on current position of the valve, closing thereby a feedback contour on temperature of air submitted to salon.

The similar image organises management демпферными by valves of a choice of a direction of distribution of an air stream, and also the valve of switching of modes of air circulation.

Base pressure of the powerful transistor drive fan K/V electromotor changes at the command of ECM that allows to regulate in steps speed of rotation крыльчатки. The remark: For protection of a chain against an overload the special thermosafety lock working at temperature 119С and providing отсечку of a food from the fan is included in it.

The evaporator temperature is supervised special established on an exit of assemblage by the gauge.


Thus, ECM, being based on the analysis of the entering information, it is capable to calculate quantity of air forced in salon (ТАО), demanded for maintenance of the temperature mode chosen by the user.

 At input of extreme values of a working range (18 and 32 С) the system is translated in the fixed condition of the maximum intensity of cooling/heating (on ТАО). In a range of values from 18.5С to 31.5С optimum value ТАО is calculated by the management module.

Instructions on application

 The Section of System of heating, ventilation and air conditioning see also.

Hand-operated models functioning of a central air of air

The principle of management is illustrated by functioning of systems of hand-operated ventilation/heating/air conditioning in the table resulted more low. On an illustration schemes of directions of distribution of air depending on switch position are presented


The percentage parity of the expense of air through corresponding air lines in various positions of the operating switch can be estimated on resulted on сопр. Illustrations to the diagramme.


Computer-controlled models functioning of a central air of air (climate control)

The Section of System of heating, ventilation and air conditioning see.

Safety measures

 In avoidance ошпаривания, do not uncover at all a broad tank and do not disconnect any components охладительного a path at the hot engine. If there is a necessity for removal of a cover of a broad tank before full cooling of a cooling liquid, (though such situations should be avoided whenever possible), it is necessary to dump preliminary superfluous pressure in system. Wrap up a tank cover a thick layer of rags, then slowly turn on before hissing occurrence. When specifying in release of steam hissing will stop, slowly turn away a cover up to the end. If at last stage отворачивания hissing does not renew, the cover can be removed. In the course of performance of all procedure do not incline the person over a tank mouth, for protection of hands put on rubber gloves!

Try to avoid antifreeze hit on open sites of a skin and a paint and varnish covering кузовных panels. Casual splashes should be washed off immediately plentiful quantity at its finest. At all do not leave merged of the engine or a fresh cooling liquid stored in open container. Passage traces at once collect rags. Remember that the sweetish smell of antifreeze is capable to draw attention of children and animals. Hit even insignificant quantity of a cooling liquid in a digestive path live to an organism is fraught with the most serious consequences, up to a lethal outcome!

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