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The logic behind replacing the coolant, rather than just topping it off, is to remove impurities. If the reason you have to add to it is that there is a slow leak somewhere, you may get by with just adding some now and then. But if the nature of the problem is that that coolant itself is being depleted, without removing any impurities, then yes, it has to ...


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You shouldn't be constantly replenishing the coolant - if you are, there's probably something wrong with your car! Modern car cooling systems are designed to be almost maintenance free, so you should only need to drain and replace it after a long interval (e.g. the 11 years you quote), rather than every two years with older systems - obviously you should ...


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It's not a totally closed system 100% of the time on most cars that I've seen, but let me explain in detail. The overflow vents to outside air and you can lose some to evaporation over time. The way that could happen is that on most cars the reserve overflow tank is not pressurized. What happens is if the pressure builds up too high in the radiator cap, ...


4

If it is not obvious from where it is leaking, your best bet is to go on a car wash, and clean the engine as much as you can. Leave the car dry, fill up the coolant, and then try to replicate the issue. Also before you try to replicate the leak, it might be a good idea to remove any plastic covers from the top and the bottom of the engine.


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When an engine goes through it's four cycles, one of those cycles is combustion. Combustion creates a lot of pressure, which forces the piston down in the cylinder. Normally, the head gasket helps contain the combustion by creating a seal between the head and the block. If the head gasket is blown and is allowing the combustion to enter into the coolant ...


3

The reason adding straight anti-freeze to a nearly full system is not recommended is because you will have no idea of the actual concentration. Most manufacturers recommend a 50/50 mix of antifreeze concentrate to water. Mixtures with too much water may not provide adequate boil over or freeze protection. Mixtures with too much antifreeze concentrate may ...


3

In general, the easiest way to drain coolant from systems like these is to disconnect the lowest fitting between the coolant hose and the engine block and let the coolant just drain out. Usually, it's near the bottom of the block itself, so it shouldn't be hard to reach from underneath the vehicle.


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The first thing I look for when we see overheat at cruise speed but not at idle is poor heat transfer through the radiator. The heat load at idle is much lower at idle than cruise. Fan generated air flow is adequate to cool the radiator at idle. Air flow over the radiator at low cruise speed is not enough to carry away the much higher heat generated at that ...


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You plug the tube from the radiator into the coolant reservoir There are two plugs on the coolant reservoir Intake Vent Typically, the intake will fill from the bottom of the reservoir and the vent will vent from the top or just near the plastic lid you can open. Brief Explanation The intake plug from the radiator needs to sit at the bottom in order ...


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Firstly, if your coolant is draining every week, then you have a major leak somewhere, and I'd recommend you get that fixed first - otherwise you may find that you run out during a journey and overheat your engine, which could result in total engine failure. Secondly, I would not recommend putting ordinary water directly in the coolant system for any length ...


3

Assuming that there was enough coolant in both the engine block and the radiator to start with (on average cars can store near 5L in each), if you're losing that much coolant at that rate, you are either: leaking it. Inspect the engine drain plug, the radiator drain plug, any bleeder values, the condition of the radiator and the condition of the hoses. If ...


3

The coolant reservoir is located directly behind the driver's seat under the carpet (not in the floor, but in the raised part). Pop open the carpet, take out the black screw, and slide out the metal cover. It's a bit tight back there - but, that's where you'll find it! Happy hunting


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Sounds like an air pocket in the cooling system. Take the cap off of the overflow tank and radiator if possible and start the engine and turn the heat on so it'll circulate fully, allow the engine to reach operating temperature and the coolant level should drop as soon as its flushed the air pocket out, top off the system, replace caps and you're good to go.


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I agree with dlu. I would check the radiator cap next if the thermostat is known to be good and the car doesn't show that it's overheating on the gauge. Here's a picture of the functionality associated with the radiator cap. The cooling system builds up a lot of pressure as it reaches operating temperature, so the radiator cap is designed to relieve this ...


2

It is probably "normal spill" while driving because the cap on this model seems rather crappy. Because if it overflowed due to overheating etc. the liquid would have come out from the pressure vent, not from the cap. (well perhaps from the cap also in this model because caps do not seem to tighten well). See this thread for nice photos and a good ...


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What you are seeing is the residue from coolant. If you look inside the overflow reservoir, you can see the standard "red" Toyota coolant, thus the reason for the red-ish looking residue. Why the residue is there is another story. It could be from someone missing the overflow while trying to pour more coolant into the jug. It looks more like there was a ...


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Start by getting as much of the oil as you can out of the header tank, then do a thorough flush of the cooling system. If you have a plastic overflow tank you may want to clean it with a bit of detergent if any of the oil got into it.


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Shove a garden hose into the plastic jug, and fill it with water such that it floats the oil up and out. Disconnect the small rubber tube, and drain out the water. Replace to the proper level with a 50/50 ratio antifreeze water mix. I wouldn't panic. Oil will neither help nor harm your cooling system. Get it cleaned out, but no panic necessary. It's ...


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If you only poured oil into the overflow, you should not have any issues. If you don't have the tools to drain the reservoir, then take and fold the hose which goes from the radiator to the reservoir, then take some string or something like which can be tied around the hose. This will keep any fluid from flowing into/out of the reservoir. Then drive directly ...


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I would start by replacing the radiator cap. If you can get the system (and the cap) pressure tested, this will help narrow it down. However, I've seen more than once a cap that tests good on a tester, but doesn't seal properly on the radiator neck. Cheap enough to buy a Stant at the parts store and see if it makes a difference.


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Failure of the cooling system? More like failure of the head gasket. Looks like the exact same material as this post, so it may also be a transmission cooler gasket. Even if the head gasket was repaired, I have experienced big problems with the cooling system afterwards. It is difficult to remove 100% of the particles pushed into the coolant when the ...


2

Cooling systems are under pressure to increase the boiling point of the coolant. This allows the system to operate efficiently without boiling off the coolant and overheating the engine. A loose radiator cap will cause the system not to pressurize, resulting in overheating. In this case, the coolant is more likely to be lost to boiling off than by simple ...


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In addition to the other suggestions, it might be a good idea to check to see if there is any coolant coming from the weep hole of the water pump. If your water pump is bad or on its way out, it won't circulate the coolant enough to keep it cool.


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If you have a constant need for coolant for replenishment you either have a problem leaking coolant or your engine is running entirely too hot. Which ever the problem may be, you have to keep the coolant level up in your car. If you don't your engine will overheat and you will be looking at damage 10 fold the price and hassle it would take to fix the coolant ...


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usually the coolant res should be between MAX and MIN mark when the engine is completely cold, but this varies by manufacture, so check your owners manual. Coolant expands when it gets hot, so when your engine is warm, the overflow tank will contain more fluid. whereas when its cold the coolant is more dense, thus lowering the coolant level.


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It’s not... There must be a leak somewhere. There are quite a few spots where you can have small, almost unnoticeable, leaks. Every hose connection in the cooling system is a potential leak as are all the gaskets. There could also be leakage at the pump shaft and at any valve. None needs to be more than a tiny bit to add up over a year or two. On my Jetta ...


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Usually it is the chemicals that prevent freezing / corrosion that evaporate which is why the annual service / test includes checking the Specific Gravity to make sure that the anti-freeze will still do its job. Make sure that the ratio is correct then, in future, add or top-up with the correct mix for the season. Edit to add information due to a comment : ...


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IMO, if the engine is cooling as it should, I would not be concerned with it. What you are seeing is fairly typical in cooling systems as they age. The buildup is either deposits from the water used to mix the coolant (that is why distilled water is recommended) or just the coolant mixture has attracted some contaminants over time. It is possible there ...


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The proper answer to this is that you should use a coolant tester to check the concentration of the chemicals in the coolant, and then top up appropriately to keep them balanced. In practice, however, I'd usually top up with the same coolant/water mix - in general, it's better to have too much coolant in the mix than too little. The amount you're topping up ...


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If you have a standard overflow tank and not a surge tank, it can have coolant in it if there is a leak in your coolant system. The simple reason is, the system works on a basis of pressure/suction. When the system is under pressure, if there's too much pressure, it will push a small amount of coolant out into the overflow bottle. Then, when the system cools ...


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