The Comprehensive Guide to Engine Coolant Additives: Enhancing Performance and Protecting Your Engine

Engine coolant additives are essential components in maintaining the health and longevity of your vehicle’s engine. These chemical compounds are added to the engine coolant to enhance its performance, protect the engine from corrosion, scaling, and freezing, and provide valuable insights into the condition of the engine and the coolant system.

Understanding the Role of Engine Coolant Additives

Engine coolant additives contain a variety of elements, including copper, sodium, silicon, potassium, molybdenum, and boron, among others. The concentration of these elements in the coolant and the engine oil can provide valuable information about the condition of the engine and the coolant system.

Detecting Coolant Leaks

One of the primary functions of engine coolant additives is to help detect coolant leaks. When a coolant leak occurs, it can result in a detectable and often sizeable concentration of copper in the crankcase oil, typically ranging from 100 parts per million (ppm) to more than 300 ppm. This copper can come from various sources, such as bushings used in rocker arms, wrist pins, turbo bearings, crankshaft and camshaft bearings, the governor, the oil pump, and the service meter drive gear.

The release of copper sulfides into the oil can lead to a rising copper concentration, which can reach well over 300 ppm. However, this is generally benign and may not be associated with cooler failure, accelerated wear, or lubricant oxidation.

Monitoring Other Elements

In addition to copper, other elements such as sodium, silicon, potassium, molybdenum, and boron can also appear in the used engine oil due to additives that are formulated with the glycol or introduced as a supplement into the coolant. By establishing a baseline for the antifreeze to determine the normal family of elements found in its formulation, you can suspect a coolant leak when the same relative concentrations of these elements, along with copper, are found in the used engine oil.

Diesel Engine Considerations

In diesel engines, copper is the second most abundant wear metal, with 95 percent of the data below 167 ppm. However, copper readings in diesel engines tend to fluctuate much more than iron readings, due to sources that can release copper into the oil at rates faster than those produced by classical wear modes. These sources can include zinc dialkyl dithiophosphate (ZDDP), heat, and new engines, which can lead to cooler core leaching, a chemical process that forms copper sulfides on the copper cooler tubes and contributes to a rising copper concentration in the oil.

Monitoring Coolant Additive Concentrations

engine coolant additives

Monitoring the concentration of the various elements found in engine coolant additives is crucial for maintaining the health and performance of your engine. Here are some key considerations:

Copper Concentration

Copper is a key indicator of coolant leaks and potential issues with the engine’s cooling system. A sudden increase in copper concentration in the engine oil, typically above 100 ppm, may suggest a coolant leak or other problems that require immediate attention.

Sodium, Silicon, Potassium, Molybdenum, and Boron Concentrations

The presence of these elements in the engine oil can also provide valuable insights into the condition of the coolant system. Monitoring the relative concentrations of these elements, along with copper, can help identify coolant leaks or other issues that may be affecting the engine’s performance.

Baseline Concentrations

Establishing a baseline for the normal concentrations of these elements in the coolant and engine oil is essential for accurately interpreting any changes or deviations. This baseline can be determined by analyzing the antifreeze formulation and monitoring the engine oil over time.

Preventive Maintenance and Troubleshooting

Regular monitoring and maintenance of engine coolant additives can help extend the life of your engine and prevent costly repairs. Here are some best practices to consider:

  1. Coolant Flush and Replacement: Regularly flushing and replacing the engine coolant, as recommended by the manufacturer, can help remove any buildup of contaminants and ensure the proper concentration of additives.

  2. Additive Replenishment: Depending on the type of coolant and the vehicle’s usage, the concentration of additives may need to be replenished over time. Follow the manufacturer’s recommendations for additive replenishment.

  3. Leak Detection: Regularly inspect the cooling system for any signs of leaks, such as discoloration, drips, or unusual odors. Addressing coolant leaks promptly can prevent further damage to the engine.

  4. Oil Analysis: Regularly analyzing the engine oil can provide valuable insights into the condition of the coolant system and the overall health of the engine. This can help identify any issues early on and allow for proactive maintenance.

  5. Coolant System Inspection: Periodically inspect the cooling system components, such as the radiator, hoses, and water pump, for any signs of wear or damage. Replacing these components as needed can help maintain the integrity of the cooling system.

By understanding the role of engine coolant additives and implementing a comprehensive maintenance program, you can ensure the longevity and optimal performance of your vehicle’s engine.

References:

  1. Copper and Your Diesel Engine Oils – Machinery Lubrication: https://www.machinerylubrication.com/Read/646/copper-diesel-engine-oil
  2. FAA Order 8110.4C Type Certification with changes 1-5: https://www.faa.gov/documentLibrary/media/Order/8110_4C-CHG_1-5.pdf
  3. Environmental Labeling Issues, Policies, and Practices Worldwide: https://19january2017snapshot.epa.gov/sites/production/files/2015-09/documents/wwlabel3.pdf
  4. FAA Order 8110.4C with chg 6 included: https://www.faa.gov/documentLibrary/media/Order/FAA_Order_8110_4C_Chg_6.pdf
  5. DEPARTMENT OF DEFENSE STANDARD PRACTICE – CADE: https://cade.osd.mil/Content/cade/files/coplan/MIL-STD-881F_Final.pdf