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The Best

Coolant Stop Leak

Handpicked
Quality-Checked
Bar's Leaks PLT11 Pelletized HD Radiator Stop Leak - 11 oz.
  • Seals leaks
  • Conditions cooling system
  • Inhibits rust and corrosion
  • Lubricates water pump seals
  • Helps control electrolysis

Read More About Coolant Stop Leak

Coolant is a substance that helps the motor components of an automobile cool down after they have been running for a while. When coolant is added to an engine, it forms a thin layer over small leaks and assists in slowing down or preventing the leak from occurring. Some coolant behaves like a solid plug and only forms a sort of seal around the open hole in the engine casing. This type of coolant is usually blue in color and is used mainly for emergency or low temperature applications. The other kind of coolant is a liquid that can evaporate fairly quickly, and is used more frequently in everyday automotive maintenance and repair.

There are two common types of coolant, and each is used in a variety of different applications. One coolant of this type is known as sodium silicate; it is similar to antifreeze. The other type of coolant used in automotive systems is made up of copper sulfate. You can find both sodium silicate and copper sulfate in common brands of coolant. Each has its own particular advantages and disadvantages.

Sodium silicate is a compound consisting of two different salts of sodium. One of the salts is known as silicic acid, and the other is known as silicic hydroxide. These compounds are added because they offer various benefits. For example, sodium silicate offers a chemical sealant that is very effective at stopping refrigerant lines from freezing. Silicic acid is also a source of plasticizers and lubricants, so it helps make the internal workings of many parts flexible and resistant to wear and tear.

The one thing you want to be certain of when choosing the right coolant for your radiator stop leaks is that it contains no additives. A common additive used to make these liquid solutions more effective at stopping refrigerant lines from freezing is polysulfide. However, the amount of polysulfide used in the mix is excessive. This additive can make the liquid too thick and sticky, and then the liquid will seep through. This is the opposite of what you want to happen with your radiator stop leaks.

Sodium hypochlorite is an additive that can help make your coolant stop leak work better if you have low pressure. If there are multiple leaks in your system at the same time, then you want to use a low pressure additive. This way, you can reduce the amount of heat coming through, which can prevent the formation of bubbles in the lines. You also don't have to deal with the additional cost of heating the engine to fix the problem. Low pressure additives work very well for this application.

If the coolant stop leak doesn't seem to be working properly, then there could be a blockage somewhere else in your cooling system. Make sure that you don't try to diagnose the problem on your own. Calling a mechanic to diagnose and fix the problem can be dangerous, not to mention expensive. If you suspect that the problem is in your engine instead, then have the vehicle towed to the nearest repair shop and get the engine looked at. It is cheaper to pay someone to diagnose and repair your vehicle than to pay for a new radiator or a new alternator.

The internet is a great place to find coolant stop leaks additives. However, the internet is not always the best place to get the specific types of additives you may need. If you need an additive that is not readily available through the manufacturer, then you will have to purchase it on your own. Most shops that sell coolant stop leaks additives will be able to tell you if the product you need is readily available from them.

There are other types of coolant leak products that you may need besides just the basic additives. Sometimes you will need to replace the heater core to correct the problem. Replacement of the heater core is often not covered by the warranty on the vehicle and is therefore a specialty job. Call the shop where you purchased the heater core to see if they carry the additional types of coolant leak products that you may need.