Why Is The Function Of The Thermostat Important?
Without the thermostat in an engine cooling system, the engine would take much longer to warm up and reach the optimal operating temperature. The radiator coolant would constantly be flowing through the engine, preventing the engine from warming up and running as efficiently as it was designed to do. Your engine is designed to withstand and function properly with the temperature of the engine. If your engine runs too cool, it will run rich and burn more fuel to run properly. Also running an engine too cold you risk the engine building up carbon deposits because the engine is not warm enough to burn off and expel dirt and gunk that will form in the engine. Also, the cabin HVAC (heating, ventilation, and air conditioning) system will take much longer to warm up, preventing your heat in the car to take much longer to work and may never warm up as hot as it could be. No heat in the car will not be pleasant on those cold days.

Optimal Engine Operating Temperature
Both the LS1 Engine found in the 2004 Pontiac GTO and the LS2 engine found in the 2005-2006 Pontiac GTO’s have an optimal engine temperature range of 195-220º F degrees Fahrenheit (91-104º C degrees celsius). The average being about 210º F. This is for stock engines with the aluminum engine block and aluminum cylinder heads.

When you start your engine cold, the thermostat valve will be closed, preventing the coolant from cooling down the engine. Once the engine reaches 187º F, the valve on the thermostat will open allowing coolant to run through the engine preventing it from overheating. This does not mean the engine will stay at 187º F because that is the temperature the thermostat opens. The engine temperature will continue to rise slightly. In my experience, the engine temperature will stabilize between 190-210º F depending on the outside weather temperatures. Should your engine go above temperatures of 219º F, the cooling fans will turn on and help to reduce the engine temperature.

2004-2006 PONTIAC GTO ENGINE TEMPERATURES

Which Thermostat Should I Use?
The factory O.E.M thermostat is an AC Delco, part number 131-156, and is a 187º F thermostat. There are also other companies that make a replacement thermostat and most should also be a 187º F valve opening. Thermostats will begin to open before the temperature rating they are designed for. Usually 3º F before the rating sometimes sooner, and will be fully open at 15-20º F past its temperature rating. The stock 187º F thermostat will begin to open at 184º F, allowing coolant to flow through the engine and begin the cooling process. The thermostat will fully open between 202-207º F should the engine temperature reach this point. This is for a stock engine with an aluminum engine block and aluminum cylinder heads. Both the LS1 and LS2 engines are designed to run at temperatures between 195-220º F. I do not recommend using any other thermostat than what was designed for the engine.

The following problems could occur if anything other than the stock thermostat is used:

• USING NO THERMOSTAT – This is just foolish. With no thermostat installed, this also means there is no valve to regulate the operating temperature of the engine and no chance for the engine coolant to stay cool. The second you start your vehicle coolant is being run through the engine, getting hotter and hotter as the engine heats up. By the time your engine reaches its optimal operating temperature, the coolant will also be the same temperature. The purpose of the radiator is the cool the coolant, but the coolant never received a chance to cool down. The coolant temperature will continue to increase and get even hotter, and eventually, your engine will overheat.
• USING A 160º F DEGREE THERMOSTAT – This is another wonderful internet myth. Using a 160º F thermostat does not keep your engine cooler. Yes, the valve on the thermostat will open faster to allow the coolant to run through the engine and begin the cooling process. The problem is, your engine does not know that is what you are trying to do. The engine is going to get hot no matter what you do. A 160º F thermostat will begin to open at 157º F, which isn’t much for an engine. The 160º F thermostat will be fully open between 175-180º. The coolant originally was not supposed to get hot until 187º F. Now you put a cooler thermostat in and the coolant starts getting hot at 160º F instead of the intended 187º F it was designed for. Your engine is now prematurely heating up your engine coolant. Again, just like running no thermostat, the coolant is trying to play catch up by running through the radiator to cool, but it’s too late because the engine already made the coolant hotter than it should be. The radiator can only cool so much, the cooling fans don’t come on until 226º F, and the end result is your engine is running hotter than it was with the stock thermostat.
  

  Note: Tuners can recommend a 160º F thermostat for tuning reasons. But the tuners will also adjust the tune for the cooling fans to come on much sooner than the factory settings, and also adjust the air-fuel ratios accordingly. I know many high-performance parts websites will recommend the 160º F thermostat as a “performance part” upgrade. But this upgrade is only for advanced tuners and not made to be just thrown on the vehicle. Unfortunately, that is not made clear to the consumer, and there have been many testimonials of consumers damaging their engine by switching to a 160º F thermostat without the proper knowledge. The correct way is to use the stock thermostat and have the cooling fans come on sooner, which can also be performed by a professional tuner.

   

THERMOSTAT REPLACEMENT – 2004-2006 Pontiac GTO

Replacing your thermostat is a fairly easy process. It can be done with very basic knowledge of hand tools and can be done in about 1 hour. The thermostat is located in the thermostat housing which is attached to the water pump. See the diagrams below for location.

WHAT YOU WILL NEED:

PART	EXPLANATION
	Antifreeze Cooloant 2 Gallons of Prestone DexCool “Ready To Use” This is the “Ready To Use” 50/50 premixed coolant. It is already mixed so you do not need to add any water. I am a fan of the Prestone brand, but you can use any DexCool brand of your choice. This will be used to refill the radiator. The radiator must be drained of coolant to replace the thermostat.
	AC Delco 131-156 Thermostat This is the O.E.M. (original equipment manufacturers) 187º F thermostat. Again, I am a fan of using O.E.M. genuine parts. You are welcome to use another companies thermostat if you like. Just be sure it is the correct part number for your car, and make sure it is a 187º F thermostat.
	AC Delco Thermostat Seal 131-169 This is the seal that goes around the thermostat to prevent leaking from the thermostat housing. Again I am a fan of O.E.M. parts. Other company’s seals can be used. Be sure to check for the correct part number. It works much like a gasket, but is made of rubber and sits in the recessed area of the thermostat housing. Always replace this part, even if you think your current one is fine. Avoid leaks right from the start.
	Fluid Drain Pan Drain pan capable of holding 2 gallons of fluid. Needed to catch the coolant drained from the radiator.
	Adjustable Pliers Groove Joint, Adjustable, or Channel Lock Pliers. Used for removing the hose clamp holding the lower radiator hose to the thermostat housing.
	Flat Head Screwdriver Can be used to remove the worm gear hose clamps should you have them, and also loosening the radiator hose from the necks they attach to. Your vehicle may have a combination of both spring hose clamps and worm gear hose clamps.
	1/4″ Drive Ratchet 1/4″ (quarter inch) drive ratchet. Will be used to remove the thermostat housing bolts.
	10mm Deep Well 1/4″ Drive Socket 10mm 1/4″ (quarter inch) drive deep well socket. This will eliminate the need for any extensions when removing the thermostat housing bolts. Will make the job much easier. Used to remove the 2 bolts holding the thermostat housing to the water pump.
	3M Very Fine Hand Sanding Pad This item is also known as a “red scuff pad”. Will be used for very fine sanding and cleaning of the thermostat housing and water pump where they meet and connect. Will ensure proper sealing to prevent coolant leaks.
	Permatex Blue Thread Lock Blue Thread Lock. Only use the “blue” medium strength thread lock. Will be used on the thermostat housing bolts during the installation procedure.
	Torque Wrench 1/4″ (quarter inch) drive torque wrench capable of torque settings of 10 lb-ft or 120 in-lbs (inch-pounds). This will be used to accurately tighten the thermostat housing bolts without over-tightening them which can cause coolant leaks or damage the parts.

Once you have everything you need, follow the procedures below:

1. Remove the radiator shroud/air baffle. Make sure the engine is cold. Do not work on a hot engine. Pop the hood open and start removing the air baffle/radiator shroud (plastic piece covering the radiator). You will need to remove this to access the radiator cap, and it will give you more room to work when removing the thermostat.
   
   Use a small flathead screwdriver to remove the 5 push pin clips holding the air baffle in place. There is one more push clip on the far right side of the picture above (not shown). Just pull out the center part of the push clips to release the pins. Once the center of the clip is raised, you can pull out the push clips. Remove the radiator shroud/air baffle very carefully. There is a metal clip in the center of the piece underneath the shroud that you can not see. Pull the shroud/air baffle up from the center carefully to release the metal clip holding it down.
2. Drain the coolant from the radiator. Next, you will need to drain the radiator of all the coolant. On the 2004 Pontiac GTO, there is no drain plug on the radiator. So to drain the fluid you must remove the lower radiator hose located on the right side (facing the front of the engine). On 2005-2006 Pontiac GTO’s there is a drain plug that can be removed on the radiator to drain the fluid. You can find this on the right side (facing the engine) at the bottom of the radiator. Before draining the radiator be sure the engine is cool. You do not want to drain the hot coolant. You are going to need your fluid drain pan for this step. Approximately 1-2 gallons will be drained from the radiator. Place the drain pan underneath the draining area.
   
   2004 Pontiac GTO – Use channel locks, adjustable pliers, or groove joint pliers to release the spring-type hose clamp from the outlet of the lower radiator hose. Slide the clamp away from the area it was holding as much as possible. If your hose clamp is not the factory spring clamp, you can simply use a flat head screwdriver to loosen the worm gear clamp and slide it away from the lower radiator outlet. Gently start pulling the radiator hose off the lower radiator outlet neck. You may need to use a flat head screwdriver to work the hose loose. Do this gently. The radiator is made of plastic and can break. Once the fluid is draining you can also loosen the radiator reservoir cap to allow faster draining. The factory 2004 Pontiac GTO does not have a radiator cap on the radiator. The coolant reservoir is used to fill the radiator. Once all the fluid is drained you can reinstall the radiator hose to the radiator.
   
   2005-2006 Pontiac GTO’s – Loosen the drain plug found on the lower right side (facing the engine) to drain the coolant. This is a wing-style plastic drain plug so use care when removing it. Gently use a set of pliers to loosen the drain plug, once it is loose, unscrew the plug by hand and completely remove it. Once the fluid is draining, go back to the top of your radiator and remove the radiator cap. The fluid should be draining much faster now. Once all the fluid is drained you can reinstall the drain plug. Tighten by hand, then use the pliers to turn the plug a quarter to a half tun more.

   Note: Antifreeze coolant is poisonous to animals. As little as 2 tablespoons can be fatal to dogs and even less for cats. Please dispose of Antifreeze Coolant safely and away from animals and your pets. Clean up all spills and dispose of any rags or towels used to clean up Antifreeze Coolant.

3. Remove the lower radiator hose from the thermostat housing. Now the fluid is removed from the radiator, you can remove the lower radiator hose from the thermostat housing. Again using the adjustable joint pliers, or flat head screwdriver depending on which hose clamp is being used, loosen the hose clamp and move away from the thermostat housing neck so you can remove the radiator hose from the thermostat housing. Gently start pulling the radiator hose off the thermostat housing by hand. You may need to use a flat head screwdriver to loosen the hose free. Do this gently and carefully, you do not want to put a hole or tear the radiator hose.
   
4. Remove the thermostat housing. There are two bolts that hold the thermostat housing on to secure it to the water pump. Use your 10mm deep well socket with the 1/4″ drive ratchet. Loosen the 2 bolts. The other bolt is located diagonally just on the other side of the water neck of the housing (not pictured). Remove the bolts by hand being careful not to drop the bolts. With both bolts removed, gently pull on the thermostat housing to remove the housing along with the thermostat. You may need to use slight force, but it will come off. Be prepared for more coolant to drip, this is normal.
   
5. Remove the thermostat from the thermostat housing. Take note of the direction and the way it sits in the housing. The thermostat will come out most of the time with the seal still attached to the thermostat. If the seal is still sitting in the recessed area of the backside of the housing, remove this as well. Before installing the new thermostat we are going to do slight preparation to prevent any coolant leaks. Taking a red scuff pad, gently sand the back of the thermostat housing that seats against the water pump. Remove any dirt and debris and make the surface clean and smooth. You do not need to sand hard, we are cleaning it more than sanding the part. Do the same to the surface of the water pump where the thermostat housing sits. Gently sand dirt and debris off of the surface leaving it clean and smooth.
   
6. Install the new seal on the new thermostat. There is no right or wrong way here. Just be sure the thermostat is sitting in the grooved portion of the seal all the way around.
   
7. Install the thermostat into the thermostat housing. There is a right and wrong way here. Be sure the tabs on the seal of the thermostat match up with the recessed tabs on the back of the thermostat housing. The thermostat seal must fit perfectly in the recessed area of the housing. This sounds much harder than it is. Line up the seal with the recessed area of the housing, much like a jigsaw puzzle piece, there is only one way it will fit properly. There are tabs on the seal that match the tab area of the recessed area on the housing. If lined up correctly the thermostat and seal will seat firmly in place and will be ready to be installed back onto the water pump. The pictures below show the tabs of the seal lining up with the tab area of the housing.
   
8. Install the thermostat housing and thermostat. Place the thermostat housing with the new thermostat installed onto the water pump. There is only one way it can go on, the water neck must be facing outward toward the fenders. Put a small dab of blue thread lock on each thermostat housing bolt before installing. This will keep the bolts from loosening and stay torqued correctly to prevent coolant leaks.
   
   The housing will probably not fit flush because the thermostat is sprung in the closed position, so get it as close as you can and install the two housing bolts by hand. Using a ratchet and the 10mm socket, gently and evenly tighten the bolts down. Do not use a lot of force to tighten the bolts just get it flush with the water pump and stop there. The thermostat housing and the water pump are both made of aluminum and can crack with excess force on the bolts.
9. Torque down the bolts. For the next step, you will be using a torque wrench. You can use either foot-pounds or inch-pounds setting. Using a 1/4″ torque wrench, tighten the thermostat housing bolts to 10 lb-ft (14 N.m). You can also use the inch-pounds measurement torquing the bolts to 120 in-lbs. This is not very hard to achieve, which is why I recommend using a torque wrench to assure you do not over-tighten the bolts. If done properly you will not receive any coolant leaks.
   
10. Reinstall the lower radiator hose. Now that the thermostat housing is tightened down, you can place the lower radiator hose back onto the housing. Use the adjustable joint pliers or flat head screwdriver, depending on which hose clamp you are working with, and place the clamps back in place. Be sure you are placing the clamps far enough on the necks that the hose clamp is holding the radiator hose fully into place.
11. Fill the radiator with coolant. Once the hoses are securely back in place, you can begin filling the radiator with the new antifreeze coolant. Use the DexCool “Ready To Use” Antifreeze.
    
    2004 Pontiac GTO – To fill the radiator you will actually be filling the coolant reservoir tank. Fill the coolant reservoir tank until the fluid is slightly above the “cold” fill level.
    
    2005-2006 Pontiac GTO – Fill the radiator using the radiator cap hole. Completely fill the radiator until it can not take any more fluid. Do this slowly. Pour some coolant in and then wait a few seconds in between pours. This will force any air bubbles in the radiator to rise to the top. As you get closer to being full, you will see bubbles rising. Fill the radiator completely and do not put the radiator cap back on until you see no more air bubbles in the fluid.
12. Start the vehicle and check for leaks. While the vehicle is running check for any drips and leaks. If you followed all the steps correctly, you should see no leaks. Let the car run for a few minutes to allow the coolant to run through the water pump. Shut the car off and check your coolant levels. Add more if needed. Start the car again and let run until the engine is warm. Check your temperature gauge and make sure the engine is not overheating Reinstall the radiator shroud/air baffle and you are done.

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The post Thermostat first appeared on Mark Quitter Racing.

There are three different cooling systems that are used on gasoline engines.

1. Air Cooled
2. Oil Cooled
3. Water Cooled

• Air Cooled systems work by expanding the surface area or increasing the flow of air over the object to be cooled, or both. An example of the former is to add cooling fins to the surface of the object, either by making them integral or by attaching them tightly to the object’s surface (to ensure efficient heat transfer). In the case of the latter, it is done by using a fan blowing air into or onto the object one wants to cool. The addition of fins to a heat sink increases its total surface area, resulting in greater cooling effectiveness. This type of cooling can be found mostly on small engines used in lawnmowers and lawn and garden tractors and some motorcycles. Motorcycles however use a combination of air and oil cooling.

Air Cooled Engine

• Oil Cooled system uses engine oil as a coolant, typically to remove surplus heat from an internal combustion engine. The hot engine transfers heat to the oil which then usually passes through a heat exchanger, typically a type of radiator known as an oil cooler. The cooled oil flows back into the hot object to cool it continuously. This type of cooling is found mostly in motorcycles where space is limited to run a water cooling system. Motorcycles will use a combination of air and oil-cooled systems to reduce engine heat.

• Water Cooled systems use a method of heat removal from components and industrial equipment by using fluid to run through the passages of the engine block and cylinder heads to cool and remove heat. In the case of an automobile engine, the fluid is run through the radiator and then into the passages of the engine. In the engine, the fluid will absorb heat and then returns to the radiator where the heat is removed before traveling through the engine again. This constant travel of fluid is what keeps the engine cool and prevents overheating.

Water Cooled Engine

All of today’s automobiles will use water-cooled systems. Of course, there are more parts involved to keep this system running properly and efficiently. Also using the correct fluid in your automobile’s cooling system is a vital part of the engine cooling process. The use of Antifreeze as the liquid coolant is extremely important to keeping your car running cool and efficiently without the risk of overheating the fluid or the risk of the coolant liquid freezing in cold temperatures. Hence the name Antifreeze.

The Coolant Paradigm
In today’s modern internal combustion engines using a water-cooled system, having the proper engine coolant is an extremely important part of your engine’s cooling system. The engine cooling system uses liquid to cool the engine. Common sense would tell us that a water-cooled system must use water as the cooling fluid. This is somewhat correct which will be explained further down in this article.

Using just water would seem like the logical choice to add to a water-cooled system. Water itself as an engine coolant could lead to some serious problems as will be discussed. Water will boil at 212º F (100º C) at normal atmospheric pressure. Using just water as engine coolant means you are in danger of actually boiling the engine coolant should your engine’s temperature rise above 212º F. While sitting in traffic on a hot day your engine can easily reach temperatures of 220-230º F which would cause the water coolant to boil. When any liquid boils, the fluid will turn into vapor. The vapor will actually push the coolant away from the metal it is trying to cool. Coolant vapor has zero cooling properties, so your engine will absolutely begin to overheat. As the temperature of the engine rises, the metal parts of your engine will become damaged including pistons, valves, water pump, and can include warping the cylinder heads and cracking the engine block.

Using just water as an engine coolant in cold climates will also lead to some serious engine problems and mechanical failures. Water freezes at 32º F (0º C). If you live in a cold climate where temperatures reach below 32º F (0º C), your water engine coolant will turn into ice, and when water freezes it expands. This means once your water coolant has frozen to ice, your radiator will crack, the coolant reservoir will crack, the water pump will crack, radiator hoses will crack, and anywhere else in the engine water coolant is being stored. This includes the engine block. Frozen water in an engine can easily crack an engine block. You may think your engine is made of strong iron or aluminum, but ice will prove it is stronger especially when trapped in an area.

Lastly, straight water in the cooling system can cause rust and corrosion. Metal and water never have and never will play well together. Water on metal causes rust. With water comes dirty water. Water doesn’t stay clean forever. The water will become dirty over time causing metal parts to form rust on them. The radiator, the engine, and cylinder heads, all contain metal parts that can become rusted over time, especially if the car has been sitting for a while not being run or driven. Corrosion and rust are something no car enthusiast ever wants to see.

The Importance of Antifreeze
We know liquid or fluid is used in a water-cooled system, but what fluid should be used? This is where Antifreeze or otherwise known as engine coolant comes in. Antifreeze unlike water has very different chemical properties. Antifreeze engine coolant actually raises the boiling point of the fluid and lowers the freezing point of the fluid. The irony is, Antifreeze actually mixes with water to accomplish this. Water has amazing qualities for cooling and is still nature’s greatest gift. Water has a high boiling point, low freezing point, and collects heat fast, and removes heat fast. Unfortunately, internal combustion engines also create a great deal of heat and need to be cooled slightly faster than what water can offer, and nature can give us extremely cold weather that can freeze water very quickly.

Antifreeze engine coolant solves the problem of both boiling and freezing points to accommodate the extreme heat of the internal combustion engine while battling the rigors of severe freezing weather. Antifreeze is made of distilled water along with a chemical called ethylene-glycol. Antifreeze can be purchased as a concentrate meaning it must be mixed with water, or as a ready-to-use fluid that is already mixed as a 50/50 (50% antifreeze, 50% distilled water) fluid. The use of Antifreeze coolant drastically improves the boiling and freezing points of the water as seen by the image below:

As stated earlier, just plain water by itself boils at 212º F (100º C) and freezes at 32º F (0º C). The use of a 50/50 mix of Antifreeze raises the boiling point to 265º F (129º C) and lowers the freezing point to negative -34º F (-37º C). The big difference is in the freezing protection which keeps the fluid from freezing inside your radiator and engine which will cause damage. It not only ensures your engine stays within a safe operating temperature range, but it also keeps the coolant from freezing.

Lastly, Antifreeze helps to keep the engine clean and rust and corrosion-free. The chemical makeup of antifreeze helps to keep the radiator, water pump, and engine corrosion-free and prevents the build-up of “gunk” that can form over time. This of course makes all the cooling system parts last much longer and optimally prevents pre-mature repair.

Orange Antifreeze vs. Green Antifreeze

The 2004-2006 Pontiac GTO uses orange Dex-Cool Antifreeze. Some of you may be asking yourself why can’t I use the green antifreeze, it’s the same stuff? Well, actually they are not the same. I’m going to sum this up as easily as possible.

• Green Antifreeze: Green engine coolants are designed for use in older cars (pre-2000), ones that contain a lot of steel and copper components in the cooling system. To protect these metallic parts from rust and corrosion, Inorganic Additive Technology (IAT) gets added to the mix.
• Orange Antifreeze: Orange antifreeze, which also defends against corrosion is made for newer cars with more aluminum and nylon parts in the cooling system. The transition from steel and copper to aluminum and nylon in engines started back in the 1990s. Due to this change, GM introduced DexCool. DexCool is a type of coolant that uses a mix of different Organic Acid Technologies (OAT) to help to help inhibit the buildup of rust and corrosion.

The 2004-2006 Pontiac GTO comes with an aluminum engine block with aluminum cylinder heads. This is why it is so important to use the correct coolant for your vehicle. DexCool antifreeze is specially designed to be used on aluminum engine parts. I recommend just using the “ready to use” 50/50 mix. It costs a little bit more than if you purchase the concentrate version, but it is already mixed from the factory using distilled water. Also using the ready-to-use version ensures you have the correct mixture in your vehicle for optimal cooling and antifreeze performance.

Components Of The Cooling System
The cooling system’s main function is to regulate the operating temperature of the engine and prevent it from overheating. The cooling system is operated by using many different parts to properly maintain the operating temperature of the engine while it is running. If any of these parts were to fail or break, it would result in the overheating of the engine which can lead to mechanical or catastrophic failure of the engine. The following parts are used in a gasoline engine water-cooled system:

PART	DESCRIPTION
Radiator:	The radiator stores the engine coolant as well as removing the heat from the coolant fluid by utilizing a combination of air and cooling fans. Air is passed through the fins of the radiator reaching the radiator core which passes the engine coolant through the cooling area before making its return to run back through the engine to repeat this procedure.
Radiator Hoses:	The radiator hoses attach to the radiator and carry the engine coolant through the water pump and make its return through the thermostat housing. One hose is for the coolant exit from the radiator, the other hose would be the coolant return back to the radiator from the engine.
Coolant Reservoir:	The coolant reservoir stores extra engine coolant to feed the radiator should the coolant level of the radiator become low. It also works as an overflow should the coolant level of the radiator become too full. You can add new coolant to the system by filling the coolant reservoir should the level of the reservoir become low.
Water Pump:	The water pump does exactly what it says, pumps water (coolant). The water pump propels or “pumps” the coolant used in the engine back into the radiator to be cooled, then through the lower radiator hose and through the thermostat to return through the engine. This is a continuous cycle to cool the engine. On the 2004-2006 Pontiac GTO, the water pump also houses the thermostat.
Thermostat:	The thermostat sits in the thermostat housing which connects to the lower radiator hose coming from the radiator. It acts as a valve to prevent engine coolant from running through the engine until it reaches a certain temperature. Once the thermostat reaches the given temperature, the valve on the thermostat will open, allowing the coolant to pass through the thermostat and make its return to cool the engine. By letting the engine warm-up as quickly as possible, the thermostat reduces engine wear, deposits, and emissions.
Cooling Fans:	The cooling fans sit in front of the radiator and push air through the radiator cooling fins and to the radiator core to help cool the coolant release heat before it enters the engine. The cooling fans are set to come on when a certain temperature is reached. The fans will not always be running. The cooling fans act as a backup to further cool the engine coolant when above normal engine temperatures are reached. The cooling fans will come on for example if sitting in stop-and-go traffic on an extremely hot day, and also when using the air conditioning because the engine works a little harder to run the air conditioning system.
Antifreeze/Coolant:	Antifreeze engine coolant is used as the fluid to cool the engine. Antifreeze has much lower freezing points to prevent the coolant from turning to ice or freeze in cold temperatures and also has higher boiling points to prevent the engine coolant from overheating and not cooling the engine as it should. Antifreeze also keeps engine parts from rusting and forming corrosion, which prolongs the life of the engine and the cooling system parts that are used by it.

How The Cooling System Works
We already know using engine coolant is what helps to keep the engine running at the optimal temperature. Running an engine too cool can result in a loss of power and efficiency. Gas, Oil, and even some of the parts in the engine require heat to work properly. Running an engine too cold can result in the engine becoming gummed up and gunk and deposits forming in the engine because the engine does not get hot enough to burn and expel these deposits. Running an engine too hot can result in engine failure from the engine parts becoming overheated and damaged such as seals and gaskets. Also, aluminum engine parts such as the engine block and cylinder heads can warp and even crack if the temperature exceeds what the parts can handle.

The diagram below will show you exactly how the cooling system works and the importance of its function for a water-cooled engine:

1. The radiator holds and stores the engine coolant
2. Blue represents the path of the cool coolant entering the water pump through the thermostat housing. This coolant will enter through the lower radiator hose.
3. Yellow represents the coolant get warming as it runs through the engine block
4. Orange represents the coolant picking up more heat and getting hotter
5. Red represents the hot coolant running through the engine before it is passed through the water pump and back to the radiator.
6. Once the coolant reaches the radiator, the hot coolant is cooled down and expels the heat it has picked up, and then the process is repeated.
7. Coolant is also run through the heater core which is how your vehicle brings heat to the cabin area inside your vehicle.

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The post Cooling System first appeared on Mark Quitter Racing.