4.1. Features of a design

The cooling system – liquid, the closed type, with compulsory circulation. Tightness of system is provided with valves in a stopper of a broad tank. The inlet valve is normally open (a gap between it and rubber laying of 0,5-1,1 mm) – at the same time the system is reported with a broad tank. When heating the engine liquid, extending, it is forced out in a tank, when cooling – comes back. The inlet valve is closed at sharp increase in pressure in system (liquid boiling), at the same time the final valve is also closed. It opens, when pressure in system reaches about 0,5 kgfs/cm2 that increases temperature of boiling of liquid and reduces its losses. Thermal power setting is supported by the thermostat and the fan of a radiator. On the carburetor engine the fan – with the mechanical drive, is installed on a pulley of the pump of cooling liquid. On the engine equipped with system of injection, two electric fans are installed before a radiator and turn on at the command of an electronic control unit the engine.

The pump of cooling liquid – bladed, centrifugal type, is given from a pulley of a bent shaft by a maple belt. A pump housing – aluminum. The roller rotates in the two-row bearing with a lifelong reserve of lubricant. The external ring of the bearing is stopped by the screw. On the forward end of the roller of a napressovan a pulley nave, on back – a plastic krylchatka. For the correct provision of a stream of a pulley of the pump the distance from a privalochny surface of a cover of the pump to an external end face of a nave has to be 84,4±0,1 mm. At installation of a cover with laying check also a gap of 0,9-1,3 mm between blades of a krylchatka and a pump housing. For this purpose it is possible to use rollers from plasticine: they are imposed on equidistant blades of a krylchatka, establish a cover, tighten nuts of its fastening, then uncover and measure the remained plasticine thickness – it is equal to a gap.

The axial and radial side play in the pump bearing is not allowed notable by a hand. At failure of the bearing or a samopodzhimny epiploon of the pump it is recommended to replace a pump cover assembled with the roller and a krylchatka.

Redistribution of streams of liquid the thermostat with a firm thermosensitive element operates. On the cold engine the valve of the thermostat blocks the branch pipe conducting to a radiator, and liquid circulates only on a small circle (through a bypass branch pipe of the thermostat), passing a radiator. The small circle includes a heater radiator, an inlet collector, the block of heating of the carburetor (on the engine 21213) or throttle knot (on the engine 21214). At a temperature of 78-85 °C the valve begins to move, opening the main branch pipe; at the same time a part of liquid circulates on a big circle, through a radiator. At a temperature about 90 °C the main valve completely opens, and bypass – is closed, and all liquid circulates through an engine radiator. The course of the main valve has to make not less than 6,0 mm.

It is possible to estimate serviceability of the thermostat on heating of the lower branch pipe of a radiator: it has to be cold until liquid temperature (according to the index) reaches 80–85 °C, and we heat when it rises to 85–90 °C. The thermostat is not maintainable. At malfunction, loss of tightness, deformation of branch pipes it is replaced.

The radiator consists of two vertical plastic tanks (left – with a partition) and two horizontal rows of round aluminum tubes with the napressovanny cooling plates. For increase in efficiency of cooling of a plate are stamped with a notch. Tubes are connected to tanks through rubber laying. Liquid moves through the top branch pipe, and is taken away through lower. In the lower part of the left tank there is a stopper for discharge of cooling liquid.

The casings directing air streams from the fan (fans) are intended for the best obduv of a radiator. On the engine 21213 the main casing of the fan consists of two half (lower and top), the lower half has a rubber sealant from a radiator. Before a radiator the additional directing casing is established. On the engine 21214 electric fans rotate in a casing before a radiator.

The broad tank is made of translucent polyethylene that allows to control visually liquid level (3-5 cm higher than a tag of "MIN" on the cold engine).

For control of temperature of cooling liquid will screw the sensor connected with the index of temperature on the dashboard in a head of cylinders of the engine. In a final branch pipe of the engine 21214 the additional sensor of temperature issuing information for an electronic control unit the engine is installed (see the Control system of the vpryskovy engine).

Sistema of heating is described in the head Sistema of heating and ventilation.