As a California-based fuel and lubricant supplier, we understand the challenges of maintaining heavy-duty equipment in extreme heat. Fleet managers often worry more about overheating than freezing, especially during the hot summers we experience here. So, it’s common for basic coolant issues and maintenance to fall to the bottom of a fleet manager’s preventative maintenance list. However, neglecting coolant maintenance can lead to significant problems, as coolant plays a crucial role in engine health and efficiency.

The importance of coolant maintenance
Coolant maintenance is not just about protecting the engine from freezing. In a heavy-duty diesel engine, one-third of the total energy produced propels the engine forward while the remaining energy dissipates throughout the engine. Engine coolant balances these heat levels by removing excess heat, which is crucial in healthy engine maintenance. When coolant is neglected, it can lead to engine breakdowns, with 40% of engine-related failures tied to coolant problems and 60% of commercial trucking equipment downtime connected to coolant issues.

Best practices for coolant maintenance
Fleet managers and mechanics must consider coolant maintenance year-round, not just during winter. Coolant issues can arise during periods of extreme heat, which can cause the coolant to evaporate at a faster rate. Here are some best practices for maintaining coolant:

  • Visually inspect the coolant: Routinely sampling and inspecting your engine coolant should be a regular maintenance task. When inspecting samples, look for suspended particles, a thin or watery appearance, or a sludge-like texture. If you notice any of these issues, the coolant is likely beginning to break down and will not be as effective.
  • Check the radiator cap: Ensuring the engine radiator cap is in good working condition is essential. If it’s cracked or not sealing correctly, the system may not properly pressurize, which could lead to overheating the coolant. This could cause the water in the coolant mixture to boil and burn off, throwing off the glycol levels of the coolant mixture and leading to further coolant problems.
  • Use a refractometer: Testing your coolant with a refractometer can tell you the concentration of ethylene glycol in the solution. The goal is always to have a concentration of at least 50%. A refractometer measures the composition of different solutions and chemical concentrations. A handheld or digital refractometer can provide a basic concentration breakdown of the coolant solution to determine the coolant’s freeze point and glycol content and see how much it may have disintegrated over time.
  • Check pH levels: It’s also essential to regularly check the pH level of your engine coolant. Extended-life coolant should be maintained at a pH level around 8 or 9. The mixture will likely turn acidic if the pH level drops below that mark. You can use test strips to measure pH levels and other common standards like freeze point, additive levels, and even the presence of contaminants.
  • Lab analysis: The best way to measure the effectiveness of your coolant is with regular lab analysis as part of your ongoing oil analysis maintenance efforts. Lab testing can provide more comprehensive benchmarks on your coolant makeup and potential performance using samples taken from your engine. Unlike test strip kits or handheld refractometer testing, which can be incorrectly done in the field, lab testing can ensure quality results so you can see exactly how your engine coolant is performing. Sign up for our oil analysis program today to get expert data on your fleet coolant.

Common coolant problems
Regularly checking your engine coolant using these methods can help protect your engine. However, visual inspection alone is not sufficient. Relying on the coolant’s color to indicate its effectiveness is a common misconception, as color is simply dye added to the mixture. Here are some main issues caused by neglected coolant maintenance:

  • Cavitation and wet sleeve liner pitting: A wet sleeve liner is inserted into the engine block to improve heat transfer in diesel engines. Ineffective coolant can lead to air bubbles that pit the steel liner, causing it to perforate and allowing coolant to leak into the engine oil and other parts, resulting in severe damage. Many coolants now contain inhibitors to help prevent this, but regularly inspecting and changing your coolant can also prevent this engine issue.
  • Scale: Coolant contains water, and minerals from the water can harden in the cooling system and form scale. When this happens, as coolant breaks down, it can reduce the efficiency of the coolant and the transfer of heat energy in the engine. When scale builds up, it can directly affect the engine hardware, leading to issues like cracked valves and heads or causing issues with the engine coolant fans, leading to engine temperature problems.
  • Corrosion: Engine corrosion happens throughout a vehicle’s life as the metal in the engine wears down over time from being used, but it can be sped up by coolant issues and lead to faster engine decline. Many coolants now contain additional additives to help reduce corrosion.
  • Silicate drop-out: Engine coolants high in silicate can sometimes develop ‘green goo,’ deposits, or sludge-like goo that forms from the phosphates and silicates in the coolant mixture. When this process begins, the ‘green goo’ can cause water pump failures, radiator blockages, and heater core problems.

The impact of neglecting coolant maintenance
Neglecting coolant maintenance can have significant impacts on your heavy-duty diesel engines. The cost of repairs and downtime can far exceed the effort and expense of regular coolant maintenance. Here are some potential implications of neglecting coolant maintenance:

  • Increased Repair Costs: Neglecting coolant issues can lead to severe engine damage, such as cavitation and wet sleeve liner pitting. Repairing or replacing engine components can be extremely costly, especially for heavy-duty equipment.
  • Downtime: Equipment downtime can be a significant issue for fleet managers. When an engine fails due to coolant issues, it can take days or weeks to repair, leading to lost productivity and revenue.
  • Reduced engine lifespan: Regular coolant maintenance helps prevent corrosion, scale buildup, and other issues that can reduce an engine’s lifespan. Neglecting maintenance can lead to premature engine failure and the need for costly replacements.
  • Decreased efficiency: Coolant issues can affect the efficiency of your engine, leading to increased fuel consumption and decreased performance. This effect can result in higher operating costs and reduced profitability for your fleet.

Making coolant maintenance a priority
Coolant issues can lead to excessive engine maintenance and equipment downtime if left unchecked. Regular coolant maintenance and testing are crucial for heavy-duty equipment to keep the vehicle in good working condition. But choosing high-quality coolants that meet your equipment’s engine needs is also essential. As your fuel and lubricant supplier, we can provide excellent coolant recommendations to keep your fleet’s engine in optimal condition, regardless of temperature extremes.

A comprehensive coolant maintenance program can help ensure the engine runs smoothly and efficiently. Here are some additional tips for making coolant maintenance a priority:

  • Schedule regular maintenance: Create a schedule that includes regular coolant checks and lab analysis. Ensure that your maintenance team is trained on the importance of coolant maintenance and how to perform the necessary checks.
  • Keep detailed records: Maintain detailed records of coolant checks, lab analysis results, and any maintenance performed. This process can help you track trends and identify potential issues before they become significant problems.
  • Use quality products: Choose high-quality coolants and additives that meet your engine’s specifications. We can help ensure you use the best products for your fleet.
  • Educate your team: Ensure that your maintenance team understands the importance of coolant maintenance and is trained to perform the necessary checks and tests. Provide ongoing education and training to keep your team up-to-date on best practices.

Coolant maintenance is not just a seasonal task but a year-round responsibility that plays a vital role in the health and performance of your heavy-duty equipment. Don’t let coolant issues fall to the bottom of your preventative maintenance list—make them a priority to keep your fleet on the road and running at its best. As your Chevron lubricants supplier,  we are here to help. Reach out to your Greg’s Petroleum representative today for assistance in choosing the right coolants for your fleet and ensuring that your coolant maintenance program is comprehensive and effective.​​