Automotive water pump seal

Types of Automotive Water Pump Seal

Automotive water pump seals have several functions, but the most important one is to stop water and antifreeze from mixing with each other by preventing internal leakage into the engine block. It is required to withstand temperatures of over 200 °C in a normal combustion engine, depending on the material composition. In turbos or high-performance engines, this can easily rise to 250 °C and beyond. Hence, they are made of materials that can withstand such adverse conditions as:

• Oil and heat resistant rubber seals

  This is the most common type and is used in the vast majority of engines. This type consists of two lips, where one seals against the water pump casing and the other against the drive shaft, block or housing. This seal wears the least and causes the least friction. Nitrile rubber seals are used for temperatures below -30 °C to 120 °C and for pressures below 30 bar. Fluoroelastomer seals, often branded as Viton, can be found in temperatures up to 200 °C and above.

• Mechanical seals

  They consist of two faces that are pressed against each other by a spring. A liquid or paste-like sealing compound is used to seal the faces and prevent internal fluidity. This type is often used in centrifugal water pumps with high-pressure circulatory systems in heavy-duty engines and commercial vehicles with extreme working conditions requiring seals that can withstand internal fluid leakage. They can also be found in the automotive electric water pump, where there is not much space applying a mechanical seal instead of a compound seal.

• Ceramic and carbon seals

  These are the most common materials used for the sealing faces. Carbon counterface has better sealing properties, but ceramic is more resistant to wear. Both materials can have a cemented tungsten carbide or graphite alloy sealing ring for additional wear resistance. Silicon carbide is also sometimes used. This is a special condition, and a mechanical seal is typically employed in heavy-duty mechanical seals with extremely high-temperature applications.

Durability of Automotive Water Pump Seal

The life of an automotive air pump depends on several factors, including the composition of its seal material, what kind of operating conditions it is subjected to, and the water pump's design. Water can be corrosive, abrasive, and aggressive and can generate a lot of heat in the engine and in its vicinity. Antifreeze and engine oil can also be aggressive and create pressure. These are some of the things that can damage the seal, so manufacturers tend to use seal materials that are less affected by these elements. For example, grease is sometimes applied on mechanical seals to improve their durability by extending time before internal fluid leak occurrence.

• Rubber seal durability

  Nitrile rubber seals can be used for 60-120 thousand km under normal conditions. Fluoroelastomer seals can be more durable from 100 to 180 thousand km.

• Mechanical seal durability

  This can be harder to quantify as it largely depends on the pump being used, the seal design, and the aforementioned factors. An industrial mechanical seal can last from 1000 hours to several years in extreme working conditions. For mechanical seals in automobiles, it can be around 60-120 km.

• Carbon ceramic, silicon carbide seal durability

  These materials have poor wear resistance, but they are highly temperature-resistive sealing faces for heavy-duty mechanical bus seals that can be durable from 1000 hours to several years in extreme working conditions.

How to Choose an Automotive Water Pump Seal

When choosing an automotive water pump seal, there are some things a buyer should consider before making a decision to buy so they do not end up buying the wrong product. Here is a guide on how to choose the right one.

• Material

  The seal material used will depend on the type of engine and the kind of environment it is working in. For an automotive water pump running in a normal temperature range, a rubber seal made from nitrile or fluoroelastomer will be more than enough. For seals in high-performance turbo engines that go above 200 °C, high-quality materials like fluoroelastomer should be used. For mechanical seals, the seal material should be resistant to internal fluid leakage.

• Engine type

  Different water pump seals are used for different engines. For centrifugal water pumps that use mechanical seals, the seal used must be suitable for the pump. Water pump seals for electric water pumps often consist of a compound seal or a mechanical seal and rarely a rubber seal. For leakage prevention from the water pump and engine, an automotive water pump seal can also be used. this seal can be used in centrifugal diesel pump, for example.

• Automotive water pump gasket

  An automotive water pump gasket is made from metal, rubber, or a combination of both. It is located between the engine block and the pump and serves as a sealing element that prevents leakage of coolant. Unlike a seal which is used to ensure two mechanical components that are in contact with each other do not mix fluids, the gasket is placed between two surfaces to prevent the two surfaces from coming in contact with each other. When selecting an automotive water pump gasket, make sure it is suitable for the engine.

Industry Advice on Making the Right Choice

It is essential for buyers to stock the following tips when choosing the right automotive pump seal in bulk.

• Quality

  Buyers should ensure that the water pump seals they plan to buy are made from quality materials to ensure they can resist heat, pressure, and corrosion for a long time. They should also get durable seals that are made with quality materials to ensure they last longer and do not need constant replacement.

• Brand

  Buyers should also stock water pump seals for the brand of vehicle they are targeting. To ensure effective sealing, the manufacturer generally designs a seal for a specific purpose, and using that exact branded seal is recommended. For those who find it hard to get the same seal used by the brand, they should ensure that the one they get has the same size and has similar specifications.

• Compatibility

  When choosing the water pump seals, the water pump itself, electric water pump kit, and mechanical seal should be used to ensure the seal is compatible with the system. Buyers also need to ensure the seals are suitable for OEM or aftermarket water pumps. Since there are various kinds of water pump seals available, it is important to ensure that the one stocked is the right one. For example, a mechanical seal, a compound seal, or a silicon carbide seal.

Q and A

Q1. Which seal is more reliable between a mechanical seal and a rubber seal?

A1: The answer depends on the conditions the water pump is working at. When working in a normal average condition, for instance, the rubber seal is more reliable. However, if the environment is more extreme and more demanding, then a mechanical sea is more reliable.

Q2. What happens to a water pump seal that is overworked?

A2: Once a water pump seal is overworked, it will start to wear, and in some cases, it will start to tear apart. In the case of a mechanical seal, it might develop internal leakage, while the compound seal might develop external leakage. Further, the pump might not function properly, causing cavitation and loss of prime.

Q3. Does the kind of fluid passing through the seal affect it?

A3: Yes, it affects the seal. The kind of substance that is sealed within the water pump will determine the kind of seal that is used. For instance, a mechanical seal is commonly found in fluids that are aggressive and well against rubber. While rubber seals are used in fluids that are less aggressive.

Q4. What is the cause of the water pump seal failure?

A4: Several factors contribute to water pump seal failure. These factors include operating conditions, seal material, and the water pump system itself. In some cases, the use of OEM water pump overhaul kits can lead to the use of cheap low-quality water pump seals that can contribute to the problem.

Q5. How often should water pump seals be replaced?

A5: The water pump seal should be replaced whenever the water pump fails or the system is serviced. In some cases, it is recommended to replace them together with the water pump.