Engine Coolants Basics and Its Classification

Engine Coolants Basics and Its Classification

Engine coolant is used to remove heat produced by the engine and transfer it into the cooling system. The coolant receives the heat and circulates it through the radiator, dissipating it back into the atmosphere. A thermostat is used to regulate the temperature of the coolant during the circulation. Although it sounds like a simple process, it is a rather crucial one. Coolant technology serves an extremely important purpose of maintaining the engine. To understand the gravity of cooling systems, a typical heavy duty cooling system circulates the equivalent of a 16,000-litre swimming pool worth of coolant every hour.

In order to regulate the engine temperature, the coolant performs other support functions such as protection from corrosion, cavitation, and scales, that commonly appear in heavy-duty diesel engines. A coolant filter is used to keep the coolant pure. The chemical combination of coolants ensure that it does not react to the many surfaces comes in contact with while maintaining the engine temperature. According to research, 40% of all engine related problems surface due to incompetent cooling systems. Thus, selecting your coolant is of prime importance.

Classification of Coolants

Determining the right engine coolant for your application could be confusing. One of the selection parameters can be colour. However, many manufacturers do not use standard colour conventions and the coolants with the same colour may have different properties. Hence, knowledge of coolant classification can help in distinguishing coolants from one another. They are typically classified based on performance and product type.

The performance generally refers to the measured performance of the coolant when tested according to industry standards or OEM specifications. This test also determines the chemical compatibility of coolant with cooling system materials. The American Society for Testing and Materials, ASTM, has developed tests that are commonly used in the coolant industry.

ASTM D3306 and ASTM D6210 are one of the most commonly applied industry standards in use today. ASTM D3306 contains numerous tests stating the requirements for light-duty coolants. The specification measures key coolant attributes like freezing & boiling points. This test also contains performance requirements that evaluate the corrosion protection of coolant under different conditions and against water pump cavitation.

The ASTM D6210 includes tests of D3306, as well as additional testing that evaluates the performance of the coolant for heavy duty applications. The primary additional requirements test the ability of the coolant to protect against cavitation of wet liners, as well as the ability to protect hot surfaces against scale. When choosing a Heavy Duty coolant, it is crucial to look for an indication that the coolant meets the 6210 standards.

Coolants can also be classified based on product type. Typically type classifications are generic terms that are related to the base type and additives used in the coolant. Although these terms can be useful in the general classification of coolant, coolants within each type will vary in composition and performance.

Conventional, Hybrid and OAT Coolants

Coolants contain additives which are added to the product to protect from corrosion, cavitation, and scale. Based on the type of additives, coolants are classified as
1. Conventional
2. Hybrid
3. OAT - Organic additive technology

Each type of coolant has one of the above as their base category.
1. Conventional Coolants

• Oldest additive technology
• Lowest initial cost
• Short service intervals
• Shortest overall life

2.Hybrid Coolants

• Old + organic additive technology
• Longer service intervals
• Short overall life
• More maintenance required than OAT

3. OAT Coolants

• Newest type of additive chemistry
• Lesser service interval
• Longest overall life
• Fewest maintenance requirement

When choosing and maintaining your coolant, be sure to look at the service interval and maintenance interval of the product. Fleetguard is one of the leading Coolant and Filter Manufacturers in India.