• The thermostat when closed prevents coolant from leaving the engine and circulating through to the radiator until correct engine temperature is reached. Usually between 80'C (180'F) and 95'C (200'F) for most engines. When  optimum temperature is reached, the spring valve in the thermostat opens, allowing coolant to circulate through to the radiator, where it is cooled.

• The engine should take 5 to 15 minutes to warm up, depending on weather conditions. If your engine takes longer to warm up, or if it operates hot, you might need to check the thermostat.

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• The water pump is a vital part of the cooling system, it has a rotating impeller (something like a fan) which moves the coolant through the bottom radiator hose, to the inlet at the bottom of the water pump. The coolant flows through the engine block to the outlet at the top of the engine, into the top radiator hose and top radiator tank. The flow then goes  through the radiator tubes, to be cooled by air passing over / around the tubes, then back to the bottom of the radiator ready to be pumped around again.

• Moving air is required to keep the radiator tubes functioning efficiently.

• Impeller type water pumps must turn rapidly to be efficient. So a worn or loose drive belt(s) can cause slippage (which may not be easily detected) and reduce coolant flow, this increases engine temperature above optimum.

• Poor water quality, foreign particles or tired (passed expect life) coolant can also degrade the impeller, pitting its pumping surface and reducing efficiency, thus reducing flow and increasing temperature above optimum.

• The water pump should be check as per your vehicle's handbook or sooner if poor quality products or poor quality water have been used. The few dollars you save on cheaper radiator products can cost $100's of dollars in replacement parts & labour later. So is the cheaper product really worth the saving?

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• The radiator cap is designed to hold the coolant at a predetermined amount of pressure in your radiator. If the coolant was not kept under pressure it would boil away. Demineralised water (the original 1900's coolant) boils at 100'C (212'F) but if the pressure is increased, the boiling temperature is also increased and the coolant can then be heated to above 100'C.

• The radiator cap can be checked with a cooling system pressure tester, to ensure that it is keeping the correct pressure within the cooling system. Your mechanic can advise if the cap is faulty and needs replacing.

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• A small version of the radiator that is used to warm the interior of the vehicle. It is usually mounted under the dash board and placed in the vehicle's internal air-conditioning system. The heat from this heater comes from the coolant circulating in the engine's cooling system, it is not an electric heater. Although there are some vehicles that do have electric air heaters but these are not the norm.

• You'll notice on your dash board an environmental control panel, it refers to the cabin environment. It is a series of heat (red) and cold (blue) sliders or buttons, with air flow indicators for fresh air or recirculated cabin air, to your feet, face, windscreen and a fan speed control.

• Their functions are quite obvious, fresh air (external air) opens a vent and as the car moves air flows into the cabin. Similarly recirculated air blocks the external vent and just pushes air in the cabin around with the fan.
• A feature I'm sure you've found useful when stuck behind a smoke or bad smell emitting vehicle, it is also useful on dirt tracks, pressurising the cabin from dust contamination...

• Both air flows use the same internal air vents and can pass air over the heater coil.
• The air passing over the heater coil, cools the coolant by convection, thus heating the air. The fan or breeze blows that air into the cabin via the vents. Adjusting the slider or button between the hot and cold setting varies the amount of air that passes over the heater coil or the amount of coolant that flows through the coil.
• As about 75% of fuel in a combustion engine is converted to heat, the coolant can get hot very quickly, a matter of minutes. 

• Coolant is passed through a radiator to be cooled by means of convection with the air. As you drive air passes through the grill of the car and through the radiator core / fins. If there is not enough air flow a heat sensor detects the lack of heat dissipation and activates the radiators cooling fan.

 
• In some cars the fan is operated directly off the engine, usually mounted on the water pump shaft, and is turned by the same fan belt that drives the water pump and the alternator. Which can prove to be inefficient in some city operations at low speeds and belt slippage problems apply...

• Some belt driven fans can be thermostatically controlled as mentioned above. This is basically a fan clutch, which reduces drive torque when it isn't needed. There are many variations on this theme from flexible fan blades, variable angles of blades and different number of blades, all depending upon the design and needs of each cooling system, each has their own merit.

• Independently mounted fans are usually electrically driven and thermostatically operated. There are no fan belts to worry about, usually quieter, less power drain on the engine and therefore less heat generated, less to cool and it can keep cooling after the engine stops. Battery power is the only concern and electric batteries are quite efficient and robust now days, so it is not that much a worry as it once was.

• Fan Belts also called V-Belts are essential to many parts of your engine.
• You should check their condition periodically, look for cracking or fraying usually when their is a seasonal change from cold to hot or hot to cold weather.
• The howling you sometimes hear from your engine can be the belt slipping, reasons being:
• Adjustment is needed of associated pulleys, usually general wear and tear on the parts.
• The belt is contaminated with road grime or wear or age.

• You should follow the vehicle manufacturer's handbook and specifications on belt properties.
• To loose it slips, meaning inefficient function of systems and too tight places excessive strain & wear on the associated pulleys and bearings.
• Generally it is also wise to replace fan belts every three years, even if they appear ok.

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• This is a sensor on the engine block in the cooling system coolant flow, it is connected to either a small red light on the side, or a small needle meter at the bottom of your dash instrument panel. Where your speedometer and other vehicle vital indicators are. Digital display vehicles actually have a temperature value, impressive!

• Red light indicators: are not as informative as the needle meter. Once the light is on you should stop as soon as practicable or you run the risk of seizing the engine. Not nice if you're a long way from help...

• Needle meter indicators are a bit more informative, you get to see a level that the needle usually sits at during normal operations. When you notice the needle is higher than usual you can take some action in a slightly more relaxed time frame. You might even be able to work out why it is so high without leaving the cabin. (hot day?)

• The digital display vehicle's are a bit more pro-active, depending on model, you might even get a verbal warning to check coolant level or status. Are the modern wonder of computers, they're only as clever as they've been programmed and they can get it wrong.

• The temperature sensor is used to determine the temperature of the coolant in your engine.
• As the coolant heats up, the temperature sensor sends this information to the temperature gauge on the dashboard. Which in turn displays that to you in some form.
• If the temperature sensor is not working properly, you will never know if your engine is running too hot.
• Your mechanic or service specialist will know the best way to test the sensor.

• The sensor is usually metal that varies its electrical resistance with heat. The dashboard gauge sends a known voltage to the sensor and expects to see a value within a predetermined range come back, the gauge display's the difference as either a light on or off, a needle sitting at a particular scale, or a value converted to a digital level and displayed. A computer can read that value and announce any special actions the driver needs to do.

• A vital part of the cooling system, connecting all the parts together to form the "cooling system" and is one of the most overlooked parts in the system. A hose is a hose, is a hose, not so ! The interconnecting hoses from radiator to engine and from engine to cabin heater and back again are very special. if not maintained correctly vital coolant can be lost and cooling system efficiency compromised.

• Radiator to engine hoses are metal coil reinforced hoses, designed to carry very hot liquids at high pressures. Poor coolant or water quality can accelerate the electrolysis of metal components, eating away the metal coil of the hose and weakening it. Resulting in burst hoses or inefficient flow of coolant around the system.

• The bottom hose usually has coolant being sucked out by the water pump to the engine, while the top hose is pressurised. So a failure of the reinforcement coil would see the bottom hose collapse and the top hose expand sideways.

• Engine to cabin heater hoses are narrower, thick walled hoses designed to carry hot liquids to the heater coil in the cabin's dash board and out again. If not properly maintained can crack and leak coolant.

• Hose clamps, these little things hold the hose onto the neck of the components they attach to and over time, by heating and cooling and vibration can become loose, slowly leaking coolant and eventually releasing the hose, usually under pressure and while your driving. These should be checked at every service period.

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• Is the centre of the cooling system, without it your automobile wouldn't go very far and without the rest of the cooling system the radiator is next to useless.  There is a whole industry just for radiator constructions, it must be one of the most interesting, if somewhat confusing to be in...

• Basically the radiator is two tanks, a top and a bottom tank, interconnected to each other by tubes. These tubes are located in the core of the radiator and have fins arranged in a way to gain maximum exposure to the air and dissipate heat from coolant passing along the tubes. Using simple convection, transferring heat absorbed by the radiator metal from the coolant to the air.

• Radiators are made out of several different metals to increase the efficiency of cooling and lighter construction. The tanks may be made out of one type of metal, the tubes another, the fins something else and so on. It is the different metals used that leads to other problems, usually electrolysis, the electrical difference between metals. Remember the science classes or TV shows about atoms, their electrons etc. that is the basis of electrolysis. It is also why metals are different from each other. Aluminum, Copper, Tin, Nickel, Steel, Cast iron, and other alloy metals can be found in the cooling system. All are required for some special function, taking advantage of the metal's special properties for engine cooling or fuel efficiency. Electrolysis is the major problem that all cooling systems must deal with.

• To arrest electrolysis your coolant should have an inhibitor built in. Some brands may need a boost and Young's manufactureCORROSION INHIBITOR FORMULA 96  for such needs. Our range of coolants all have inhibitor: Young's ANTIFREEZE/ANTI BOIL ECP583 and Young's  COOLANT PRE-MIX

• Over time (years) or through poor maintenance, the cooling system may have particles floating in the coolant and circulating around the system. These particles, minute as they are, are from metal fatigue of engine and radiator components and may also be from foreign material introduced by poor quality water, which can block the tubes of the radiator and reduce the cooling efficiency. In such circumstances a radiator flush is required.

• Young's manufacture a "Clean-A-Core" suitable for such situations.
• To boost the inhibitor function of your coolant use: Young's CORROSION INHIBITOR FORMULA 96
• To replace your coolant use: Young's ANTIFREEZE/ANTI BOIL ECP583 or  COOLANT PRE-MIX
• Always FLUSH the system before changing brands, Never Mix Coolant Brands.

• Note: Inhibitor by itself in the cooling system is NOT a coolant, they may be the same colour, feel the same viscosity but they are not the same thing. Don't be fooled by the mis-information agents...
• Your automobile's cooling system is engineered to protect your investment and it deserves the best!

• Coolant is usually a green colour liquid that really has to do more than just "cool", it must protect the different metals by arresting electrolysis, lubricate any moving parts and transfer heat in the cooling system to the radiator efficiently. Water alone can no longer serve as coolant in the system, you MUST use a glycol based coolant.

• Note: Red coloured coolant may not actually be coolant but an inhibitor fluid only. Check your handbook carefully, if it states that coolant has been installed at factory then it is probably is coolant, if it is an option available from your car dealer then ask your dealer. If the fluid must be changed with 15,000Km or 12 months then it is most likely only an inhibitor fluid. Change to a coolant as soon as practicable, its probably twice as expensive but can last 3 times longer.

• Ethylene glycol has very good heat transfer properties and is used for this reason.
• Young's Manufacture a concentrate and a premix (ready to use) coolant:
• ANTIFREEZE/ANTI BOIL ECP583  and COOLANT PRE-MIX

• Over time (years) or through poor maintenance, the cooling system may have "rust type particles" floating in the coolant and circulating around the system. These particles are from metal fatigue of engine and radiator components and may also be from foreign material introduced by poor quality water at service top ups.

• To remove these unsightly particles you have two options:
• 1. Cheap, fast and effective Young's Go Clear / Rust Buster will convert the rust and turn the water clear.
• 2. Replace the coolant. (If it really looks bad or if option 1 hasn't done a complete conversion.)

• Flush the system first. Young's Clean-A-Core is recommended, follow the instructions on bottle.
• Drain and replace with new coolant.

• Young's Antifreeze/Anti Boil ECP583 or our Coolant PreMix is recommended.
• Any top up later should be with the same brand coolant. e.g. Young's. 

• Coolant does have a operational life, which is usually years or in 1000'sKm, see our Cool' Hints Page.
• Test the current status of your coolant with Young's Test Strips which measure the glycol content.

• As coolant expands when heated (or frozen) the excess needs to be stored, not thrown away, that is the function of the overflow tank. As the coolant heats up and expands from engine operation or air / steam pockets, the excess is stored. When the weather or engine operation conditions change, the required volume in the cooling system may vary requiring more coolant which the overflow tank supplies.

• In very cold climates (Snow field areas in Australia) and when the engine has been off for a while, parts of the coolant / system can reach freezing point. As it does, it expands, pushing a sluggish fluid in to the overflow tank. Remember those science experiments at school or the ice cubes in the freezer, water expands when frozen, it is the only substance that does, everything else contracts. The glycol in the coolant can only lower the freezing point, it can't arrest it. It is also possible to burst the radiator if a very cold climate is encountered. Although in Australia heat expansion is the normal condition for the overflow tank to handle. 

• A cooling system with an overflow tank is virtually a closed system, coolant can flow between the system and the overflow tank as it expands and contracts. If the system is functioning properly, no coolant is lost and there is no costly top ups every few days. If you are having to top up, see if you can find any leaks around hose clamps, radiator tubes, water pump, engine block or heater. You are looking for a green slime trail.

 

 
 
 
 
 
 
 
 
 
 
 
 
 

If you do find a leak, Young's Super Sealwill plug it until you can get it repaired.