The engine cooling system is liquid, closed type, with forced circulation of liquid.

The system consists of a cooling jacket in the cylinder block and cylinder head, radiator with electric fan, heater radiator, expansion tank, water pump, thermostat and hoses

The circulation of the liquid in the system is created by a water pump. From the pump, the liquid is supplied to the engine cooling jacket, washes the cylinders, combustion chambers, throttle assembly, heater radiator (at low temperatures) and then flows to the thermostat.

Depending on the position of the thermostat valve, liquid enters the cooling jacket (at low temperature) or the radiator (at high temperature).

Radiator with horizontal fluid flow, with tubular-strip aluminum core and plastic tanks. There is a drain cock at the bottom of the left radiator tank.

 Особенности системы охлаждения двигателя Hyundai SolarisОсобенности системы охлаждения двигателя Hyundai Solaris

In the tanks are made inlet and outlet branch pipes of the hoses to the water jacket of the engine and the filler neck.

The expansion tank serves to compensate for the changing volume of the coolant depending on its temperature.

It is made of translucent plastic. The reservoir body is marked "F" (full) and "L" (low) to check the coolant level.

The reservoir is connected with a hose to the radiator filler neck.

A centrifugal water pump provides forced circulation of fluid in the cooling system, is installed on the front surface of the cylinder block and is driven by a poly V-belt from the crankshaft pulley.

 Особенности системы охлаждения двигателя Hyundai Solaris

The pump has sealed bearings that do not require relubrication.

The pump is replaced when a radial play of the pump shaft or a coolant leak from the control hole appears

The pump cannot be repaired, therefore, in case of failure (fluid leakage or damage to bearings), it is replaced as an assembly.

A thermostat with a solid heat-sensitive filler maintains a normal operating temperature of the coolant and shortens the engine warm-up time.

The thermostat is installed in a housing fixed to the cylinder head.

 Особенности системы охлаждения двигателя Hyundai Solaris

At a coolant temperature of up to (82 ± 1.5) ° C, the thermostat is completely closed and the liquid circulates in a small circuit, bypassing the radiator, which speeds up the engine warm-up.

At a temperature of (82 ± 1.5) ° С, the thermostat begins to open, and at 95 ° С it opens completely, providing circulation of liquid through the radiator.

Usually the thermostat is replaced when the valves are stuck, either in open position or in closed position.

In the closed position, if the valve gets stuck, the engine overheats, the coolant flows in a small circle, bypassing the engine cooling radiator

If the thermostat is stuck open, the engine does not warm up enough or takes a long time to warm up.

The electric fan of the cooling system (with a plastic impeller) serves for additional airflow to the radiator; it is switched on and off by a signal from the electronic engine control unit.

Moreover, depending on the intensity of the thermal regime and the operation algorithm of the air conditioner, the electric fan can rotate at low and high speeds.

Changing the fan speed is provided by the engine control unit by connecting an additional resistance.

 Особенности системы охлаждения двигателя Hyundai Solaris

The electric fan assembly with a casing is fixed to the radiator of the cooling system.

The system is filled with a liquid (antifreeze) that does not freeze at ambient temperatures down to –40 ° C.

Cooling system capacity 5.3 liters

Possible malfunctions of the cooling system and methods of elimination

The engine gets very hot

Low coolant level in expansion tank - Add coolant

Faulty thermostat (valve stuck closed) - Replace thermostat

Water pump defective - Check the pump and replace if defective

Radiator core clogged with dirt and insects - Wash the outside of the radiator core

Radiator pipes, hoses and engine cooling jacket clogged with scale and sludge - Flush the cooling system and refill with fresh coolant

The electric fan does not start due to an open circuit in the sensors, failure of sensors, relay or fan motor - Check and repair the electrical circuits. Replace sensors, relay or electric fan assembly if necessary

Damage to the valve in the radiator filler cap (the valve is constantly open, causing the system to be under atmospheric pressure) - Replace the filler cap

Constant decrease in coolant level in the expansion tank

Expansion tank leaking - Replace expansion tank

Radiator leaking - Replace the radiator

Coolant leaks from leaking connections on pipes and hoses - Retighten the hose clamps

Water pump seal damaged - Replace water pump

Water pump housing gasket damaged - Replace gasket

Cylinder head bolts are not tightened enough (during long-term parking on a cold engine, a coolant leak appears at the junction of the cylinder head with the cylinder block, in addition, traces of coolant may appear in the engine oil) - Tighten the cylinder head bolts to the required torque (see How to replace the cylinder head gasket of the Hyundai Solaris engine).

Replace the damaged gasket, restore the tightness of the plugs

Heater radiator leaking - Replace heater radiator

The engine overheats, cold air comes from the heater

Excessive coolant level drop due to leakage or damage to the cylinder head gasket causing vapor lock in the engine water jacket - Repair the coolant leak.

Replace damaged cylinder head gasket

The engine does not warm up to operating temperature for a long time

Thermostat defective (valve stuck open) - Replace thermostat

Replacing the coolant

We prepare the car and install it on a lift or a viewing ditch

Before changing the coolant, you must wait until the engine has cooled down so as not to burn yourself with vapors or the liquid itself

 Замена охлаждающей жидкостиЗамена охлаждающей жидкости Hyundai Solaris

We turn the filler cap of the radiator of the engine cooling system by 90 °

And remove the plug

 Замена охлаждающей жидкости Hyundai SolarisЗамена охлаждающей жидкости Hyundai Solaris

We substitute the container for draining the liquid under the radiator valve of the cooling system, which is located in the lower left part of the radiator

We unscrew the drain valve plug by two or three turns and drain the liquid and the radiator

Tighten the drain valve plug

 Замена охлаждающей жидкости Hyundai SolarisЗамена охлаждающей жидкости Hyundai Solaris

We squeeze the clamp of the lower radiator hose with pliers and move the clamp along the hose

Remove the hose from the radiator tank nozzle and drain the fluid from the engine into the prepared container

Install the lower radiator hose

 Замена охлаждающей жидкости Hyundai SolarisЗамена охлаждающей жидкости Hyundai Solaris

We open the cap of the expansion tank and remove the remaining coolant from the tank using a rubber bulb or a technical syringe.

We fill the engine cooling system by pouring coolant into the filler neck of the radiator until it begins to overflow from the neck into the hose to the expansion tank.

Close the filler cap tightly

 Замена охлаждающей жидкости Hyundai Solaris

Fill the expansion tank with liquid up to the "F" mark on the tank wall

We start the engine and warm it up to operating temperature (before turning on the fan)

Then we stop the engine and, if necessary, add liquid to the expansion tank to the mark "F"

When the engine is running, observe the coolant temperature on the gauge.

If the pointer reaches the red zone, and the radiator fan does not turn on, turn on the heater and check what air passes through it.

If the heater supplies heated air, most likely the fan is faulty, and if it supplies cold air, then an air lock has formed in the engine cooling system.

To remove it, stop the engine, let it cool down and unscrew the filler cap. Start the engine, let it run for 3-5 minutes and close the filler cap.

 Замена охлаждающей жидкости Hyundai Solaris

To better fill the system without air pockets, periodically squeeze the radiator hoses with your hand.

After a few days of car operation after changing the coolant, check its level. Refill the level if necessary.

If, after a very short time, the color of the fresh liquid turns brown, it means that you have poured a fake into which the manufacturer “forgot” to add corrosion inhibitors.

In addition, one of the signs of a fake is a sharp complete discoloration of the liquid. Good quality coolant dye is highly durable and will only darken over time.

Liquid tinted with linen blue becomes discolored. This "antifreeze" must be replaced as soon as possible.