Automotive sealants
Content
Automotive sealant is a viscous, paste-like substance that is used to seal leaks in a car. With the correct application of the composition, the flow of antifreeze, water, oil and other automotive fluids can be eliminated. It can also be used for bonding various surfaces and filling cracks.
Types of automotive sealants
Automotive sealants can be classified according to many criteria, but the most extensive of them: by composition (silicone, anaerobic, synthetic, polyurethane and temperature) and by field of application (for the body, for tires, for the exhaust system, for the radiator, for glasses and headlights , for the engine, etc.).
Silicone sealants
Silicone-based sealants are heat-resistant and withstand temperatures up to +300 °C. They can be used for most engine components. The material fills gaps up to 6 mm thick, is resistant to high pressure and work speeds.
When working with silicone high temperature sealant for a car, it is necessary to thoroughly clean the parts to be joined, which is a small minus.
Scope of silicone compositions: sealing gaps up to 7 mm in size on any surfaces of engines, gearboxes, front and rear axles of a car, joints and mating of cylinder liners, as well as for gluing plastic and glass parts - headlights, sidelights, hatches, brake lights.
Anaerobic sealant
Anaerobic sealants consist of a material that hardens on contact with metal surfaces in narrow gaps where atmospheric oxygen cannot enter. Therefore, in order for the composition to polymerize, it is necessary to tightly connect the surfaces of the parts.
The advantages of anaerobic compositions also include high resistance to aggressive chemical environments, vibrations, pressure drops and temperatures. The formulation also prevents corrosion, oxidation, gas and liquid leakage.
As a disadvantage of the material, one can name the filling of relatively small gaps from 0,05 to 0,5 mm. An activator will be needed to polymerize the composition on non-metallic surfaces or at low temperatures.
The scope of anaerobic sealants is sealing, fixing and sealing threaded and flanged joints, cylindrical parts and welds.
Synthetic sealant
Synthetic sealants are a relatively new material that has not yet gained much popularity among auto mechanics and motorists. However, this material has a number of advantages:
High elasticity.
Resistance to high humidity, ultraviolet, mechanical damage.
High adhesive properties, which avoids pre-treatment of the surface before using the sealant.
Ease of use.
Multifunctionality and versatility.
Some auto mechanics and car enthusiasts attribute its versatility to the disadvantages of the material. Many people prefer narrow-profile sealants designed for specific elements and components of the car.
Polyurethane sealant
Bonds different surfaces and is produced in a range of colors, which allows you to choose a shade for repairs in a conspicuous place. Polyurethane compounds are used as sealants for gluing car window panes, for repairing headlights, for sealing seams, and also for eliminating gaps in body elements.
temperature sealant
Used for all engine components and other parts. Mixtures are created that can withstand heat up to 3500 degrees. But for repairing engine compartment parts, it is enough to withstand up to 2000 degrees.
Areas of application of autosealants
Depending on the purpose, the product is used as a sealant for:
car headlights. Allows you to restore the tightness of the optics in case of damage or replacement of headlight glass.
car windows. The best way to hermetically glue the auto glass windshield of a car and other modes of transport;
car engine. The best way to ensure the safety of structural elements of the power unit. They are used when replacing the pump, for sealing the valve cover and the transmission pan;
automobile tires and disks. Helps out in emergency situations, i.e. at punctures and damages of chamber and tubeless tires. Allows you to quickly perform repairs in the street;
car air conditioner. It helps not only to eliminate, but also to prevent refrigerant leakage, therefore it is often used as a prophylactic;
car seams. It is used in body repair - for sealing the seams of the hood, trunk, bottom, doors.
thread sealing. Compositions designed for threaded connections prevent leakage at the landing sites of hoses and pipes. Provides a tight thread fit even under high pressure.
Sealant Selection Criteria
When choosing a sealant, you should pay attention to the compliance of its technical characteristics and the features of the operation of parts.
An important parameter for choosing a sealant are the properties of the active substances in the composition of the product: the degree of resistance to pressure and vibration loads, elasticity after hardening and durability.
The presence of a dispenser and the need for a caulking gun also play a role in the choice of caulking agent.
If the sealing compound is characterized by poor resistance to high temperatures, it should not be used on engine parts.
There is no need to buy sealants in large volume packages: it is not worth storing the remaining sealant, as it will lose its properties over time.
Motorists also pay attention to how long the substance dries. As already mentioned above, anaerobic compositions harden only in the absence of contact with oxygen. This means that the driver has time to calmly and without haste apply the agent to the surface of the parts and connect them without fear that the substance will harden ahead of time.
Silicone sealants cure within 10 minutes, but do not require special application precision, so they can be used even by inexperienced drivers. On the other hand, the use of silicone products is appropriate when sealing deep gaps, while anaerobic compounds are able to fill irregularities with a depth of no more than 0,5 cm.
Detailed recommendations for the use of sealants, as well as information on how long the sealing composition takes to dry, can be found in the instructions supplied by the manufacturer. see also
