Hot answers tagged

35

I have heard (from an auto store clerk) that running just water will cause overheating. Well, that's not true. Water isn't the cause of overheating. Your coolant mixture (of whatever proportion) and radiator work together to get rid of the heat. If it's not hot, you won't overheat. However, when it is hot, the coolant can only absorb heat up to its ...


30

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 ...


24

"Is it safe to continue driving with low coolant as long as I continue to watch the temperature gauge? " No, the temp sensor reads coolant temperature, if the coolant gets low enough to be below the temp sensor, now the sensor is reading metal temperature of the area it is screwed into (usually cylinder head), by the time it reads too hot on the gauge the ...


23

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 ...


23

There's a very straightforward answer to this question: Water has a much, much higher capability to transfer heat than oil. Even if you were able to overcome the safety and design issues brought up in other answers, you'd still have to overcome the fact that water has a huge performance advantage at transferring heat compared to other common fluids (...


17

Do not pour it down the drain, and do not pour it outside. Coolant is very sweet tasting to animals and they will "drink" it. It will affect both their kidneys and GI tract with potentially fatal consequences if not treated. Typical symptoms include vomiting, thirst, lack of appetite and unusual lethargy. If you pour it down the drain, it will pollute ...


15

There are silicate antifreezes, used in most domestic cars until recent years, and OAT antifreezes, used in Japanese cars because of their domestic market testing. In OAT antifreeze the silicate has been replaced with phosphates. Domestic cars today all use OAT now, with Chrysler the last to switch. See: http://www.sae.org/mags/aei/mater/11284 So any OAT ...


14

Normally, I would ask first in a comment but that seems to be a privilege not available to new users, so here goes: Are you sure it was the radiator cap and not the overflow bottle? The radiator is usually full and getting 100ml in would be a struggle, not to mention that the green coolant would be staring you in the face. If you radiator wasn't full then ...


14

Number one answer is always Head Gasket. The reason is that there are oil and water passages in close proximity, being separated by a gasket (which might just be flimsy paper or rubber, but is often steel or copper) sandwiched between two pieces of metal with (usually) different thermal expansion rates. This means that any time your engine gets far enough ...


13

I think the main reason for this is convenience. It's an easy place to run the water pump. If you ran it out to a fan belt, it would be in the way of the timing belt while doing it, or it would be a really awkward mess trying to work around it. The second reason is for compactness. With the water pump stuck out of the way, it physically makes the engine ...


13

There are two kinds of coolant long life and conventional. Conventional coolant uses silicate salts as a "preservative" per se. They help to reduce corrosion and what not. Long life coolant uses organic acid to do the same thing. The organic acid lasts longer than the silicate salts. Mixing the two kinds of coolant is not recommended. Adding long life ...


12

Check your location's laws, but the EPA says it's not hazardous waste. If you're just a DIY-er, you can probably pour it down your toilet. Try and find a recycler first though. In St. Louis, MO (my example), I have not found a better way for a DIY-er to dispose of it, but I believe professional shops have some way to dispose of it not accessible to us. ...


12

If you do not have any leaks, then your coolant is most likely getting burned and/or going into your oil. My guess is going to be a problem with your head gasket or some crack or warping in the head. I believe coolant in oil used to turn oil more brown and make it more foamy or milky. These days, the detergents and dispersants in modern oil can reduce ...


12

Yes what you presume is correct. Depending on total volume of coolant (different for each vehicle) how much pure AF I put in, anywhere from 1/2 to 1 gallon, then top off with 50/50 mix. It is better to be over the 50% mix than under, you can go as high as 70%, so don't worry about putting a little too much pure AF after flushing the cooling system with ...


11

Straight coolant does not have the cooling properties of water. Straight water causes corrosion, freezes at too high of a temperature, and boils at too low of a temperature. The range to shoot for is between 50/50 to 70/30 Coolant/water


11

Engine safety. If you lose an accessory belt driven water pump, you're likely to keep driving, thinking the "oh, I just don't have an alternator" while you're busy cooking your engine beyond repair (normally with no temperature notification/change, if anything it'll read cold). When the water pump is on with the timing belt (or geared to crankshaft as is ...


10

Without water and without antifreeze or just without antifreeze? I'll assume that you mean without either, but there is a big difference. This is really simple though. The engine will overheat, quickly, and the seals and gaskets will give out, letting fluids leak in and out of places they should or shouldn't be (like the radiator and water pump, for ...


10

I can see a few reasons to do this: The weather in some places will be so cold that even with the thermostat fully closed the cooling system isn't able to warm the engine up to operating temperatures. Inhibiting air flow through the radiator will reduce the amount of heat rejected to the surroundings, allowing the engine to get up to temperature. The cold ...


10

First, you do need to find out where the coolant is going. There is UV dye that can help with this, and if your car is smoking, that could be a sign that the coolant is leaking into the engine rather than on the ground. For the main question, "Is it safe", as long as you keep an eye on the temperature and it's not getting too high, you should be OK in the ...


10

The coolant capacity of the 2004 TOYOTA COROLLA 1.8L 4-cyl Engine Code [R] 1ZZ-FE is 6.9 quarts. To accurately ensure you have a 50/50 mix in your system after a flush (assuming you actually flush it until you have clear liquid draining out), is to add 1/2 of the coolant as straight coolant (not 50/50 mix), then fill the rest as distilled water. For ...


10

It is unlikely that you would be able to drive a car without coolant for three weeks. I suspect what actually happened is that there was a coolant leak, possibly (probably) as a result of the work carried out to your car. It's likely to have been a small leak and it's taken three weeks for what remained of the coolant to seep away. What I would say is to ...


10

I am assuming that by cooling you are referring as to which Engine cooling systems are better in particular scenarios... Oil-cooled: Traditional Oil-cooled engines are most commonly found in passenger commuter motorcycles which are usually anywhere between 50cc to 500cc (some sophisticated models have liquid cooled engines as well). The system uses the ...


9

The main ingredient in automotive antifreeze, Ethylene glycol, has a higher boiling point when mixed with water than water alone. Wherever you live, I bet it's not Arizona or Texas. Steam voids suck, you don't want any in your cooling system. Antifreeze also contains corrosion inhibitors. I bet you don't have hard water, either.


9

First thing I'd try to figure out is how quickly it leaks - run it, stick your head underneath it as check if there is any visible leaking. If there is, chances are that it's not going to make it for 30 miles. I'd also check for any evidence of oil and water mixing. If there is, don't drive it. If it's not leaking that badly I'd be tempted to top it up with ...


9

I agree with Timo - if it is a big enough leak that you can see it clearly, then getting the car transported is much safer. In general, using water as coolant is OK for a short time or as a "get you home" alternative, but it does not have the anti-freeze and corrosion inhibiting properties of a proper coolant mix, so should not be left in the engine for ...


9

As explained on this page, using pure antifreeze alone will not do the job: No matter which type or color your antifreeze is, it will transfer heat away most efficiently when blended with the proper amount of water - a mixture percentage based on the lowest temperatures typically seen in your climate. Most regions are best suited to a 50/50 water-...


9

What is engine coolant? Engine coolant is a water and antifreeze solution. Because water has good properties as a coolant, antifreeze is used in internal combustion engines and other heat transfer applications, such as HVAC chillers and solar water heaters. The purpose of antifreeze is to prevent a rigid enclosure from bursting due to expansion when water ...


9

If it has an engine oil cooler, that is most likely the problem, a faulty oil cooler, some are made into the radiator, others have heater hoses running to a remote oil cooler, and a few I have seen are where the oil filter screws on, the oil cooler has a leak into the coolant side. The reason no coolant is in the oil is because it is a high pressure leak, ...


9

Its not good to run with low coolant, even worse to run with no coolant. Actually it can be quite disastrous (possibilities include blown head gaskets, seized pistons and a number of expensive repairs), but many times this is a result of a leaky radiator cap which is easy (and cheap) to replace. Someone already mentioned the dyes for detecting leaks, but ...


9

Hmmm, about the benefits/drawbacks, I first wanted to complain that this stuff only has a heat capacity of 2.6J/(g * K), while water has 4.2J/(g * K). Water has an exceptionally high value, which makes it a great coolant, while other liquids are normally in the range below 2.4J/(g * K). However, water is usually mixed with anti-freeze, a 1:1 mixture has a ...


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