A leaking Charge Air Cooler (CAC) can significantly affect diesel engine performance, fuel economy, and long-term reliability. Unfortunately, CAC leaks are not always easy to identify because, unlike a radiator leak, they do not necessarily leave visible fluid beneath the vehicle.

Recognising the warning signs early and performing regular pressure tests can help prevent costly repairs, unnecessary downtime, and damage to other engine components. With high-quality cooling solutions and reliable testing equipment from Dura-Lite, fleet operators and technicians can identify problems before they become major expenses.

What Causes a Charge Air Cooler to Leak?

Charge Air Coolers operate under demanding conditions, exposed to high temperatures, vibration, pressure fluctuations, and road debris. Over time, these stresses contribute to leaks caused by weakened joints, damaged tubes, failing seals, or structural fatigue. Poor-quality materials and manufacturing inconsistencies also increase the risk of premature failure.

Choosing a durable CAC is essential for maintaining dependable engine performance. Dura-Lite Evolution® Charge Air Coolers are engineered for performance, fuel economy, and longevity. Its proprietary high-temperature silicone grommet leak-free tube-to-header seal system is designed to deliver dependable sealing, while reinforced tanks help reduce premature failure.

For more than 30-years Dura-Lite has experienced a failure rate below 1% for its Evolution Charge Air Coolers. Dura-Lite backs its Evolution coolers with a 7-year, million-mile guarantee, demonstrating its commitment to durability and reliability.

Although no mechanical component can be guaranteed never to leak under every operating condition, Dura-Lite's design and manufacturing approach aims to minimise common failure points and provide long-lasting performance.

How Do You Pressure Test a CAC?

A pressure test is the most reliable way to determine whether a charge air cooler is leaking. Dura-Lite's Tester-Kit™ makes the process straightforward and can typically test a CAC in 20 minutes or less.

Follow these four basic steps:

Step 1: Remove the turbo hoses and clamps.

Ensure the engine is turned off, and the charge air cooler is cool. Disconnect the relevant hoses and clamps to access the CAC inlet and outlet. Check that the connections are clean and free from debris.

Step 2: Install the test plugs and safety clamps.

Select the correct rubber test plugs for your cooler's openings. Fit the plugs, safety clamps, gauge, and associated components securely, then double-check the connections before introducing compressed air.

Step 3: Apply pressure and check for leaks.

Using the Dura-Lite Pressure Gauge Assembly, apply 30 psi of air for typical heavy-duty applications, provided this matches your vehicle manufacturer's specifications. Disconnect the air supply and monitor the gauge for pressure loss over the specified period. Compare the result with your manufacturer's leak-down rate specification for the engine in reference.

Step 4: Release the air.

Carefully release all remaining pressure before removing the plugs and clamps. If the pressure loss exceeds the allowable leak-down rate specification, investigate the cause, and replace the faulty cooler as required with a Dura-Lite Evolution CAC.

Always follow the vehicle manufacturer's testing specifications and the instructions supplied with the kit. Never exceed the permitted pressure.

Charge Air Cooler (CAC) Pressure Tester

Accurate testing requires the right equipment. The Dura-Lite Tester-Kit™ is specifically designed to pressure test most heavy-duty charge air coolers safely and efficiently, helping technicians identify leaks before they lead to reduced performance or expensive engine repairs.

The kit includes a range of rubber test plugs, stems, washers, clamps, a pressure regulator, and a pressure gauge. Its components feature high-quality materials and protective coatings to help resist corrosion and extend service life. Replacement parts and non-standard rubber plug sizes are also available for special applications. The kit comes with a one-year warranty.

For workshops and fleet maintenance teams, having a dedicated CAC pressure tester makes routine inspections easier to incorporate into preventative maintenance schedules. Dura-Lite recommends testing the charge air cooler whenever a vehicle is serviced or its oil is changed, helping detect leaks before symptoms become severe.

Discover the Dura-Lite CAC Tester-Kit and explore the four-step CAC testing procedure.

Protect your engine performance with proactive CAC testing. Identifying leaks early and choosing a dependable Dura-Lite Evolution replacement cooler will help improve fuel efficiency, reduce downtime, and support long-term engine reliability.

Demand Excellence! Demand Performance! Demand Quality! Demand Dura-Lite!