When cooling systems are not maintained, it can cause cooling problems, overheating and radiator failure. Today’s coolants last a long time (up to 5 years or 150,000 miles, which ever comes first), but they are not lifetime coolants. Eventually, the corrosion inhibitors in the antifreeze wear out and allow electrolytic corrosion to attack the system from the inside out.
The most vulnerable components in the cooling system are the radiator and heater core, especially lead soldered copper/brass heat exchangers in older vehicles. Aluminum radiators and heater cores in newer vehicles are better able to withstand the corrosive effects of worn-out coolant, but not forever. Eventually, the metal will be eaten away, creating pinholes that allow the radiator to leak. This type of damage is usually too extensive to risk patching, so replacing the radiator core or the radiator itself is usually necessary.
Many aluminum radiators have plastic end tanks. Plastic won’t rust or corrode, but it can be eroded by sediment circulating in dirty coolant. Sediment can have an abrasive effect that scours away at the soft plastic. Plastic also doesn’t handle severe overheating very well either. Hot steam can literally melt a hole right through an end tank!
The rubber seal between the plastic end tanks and the radiator core can also be a source of trouble. Vibration and thermal expansion/contraction can loosen the seal, causing the radiator to leak. This type of leak can be difficult to repair because the core is clamped to the end tank. Repairing an end tank leak requires special equipment and the services of a radiator repair shop. Cooling system sealer may temporarily plug a small leak, but sooner or later the radiator will have to be repaired or replaced.
Clogging is another problem that can prevent a radiator from cooling properly. Rust and scale in the cooling system can clog up the small passageways in small radiator tubes. Cleaning the cooling system may get rid of most of the contaminants. But a clogged radiator can be very difficult to clean, and usually has to be removed and disassembled for professional cleaning in a hot tank, or replaced.
Repairs at a radiator shop can be time-consuming and expensive, often taking several days and costing hundreds of dollars. That’s why replacement radiators have become so popular. They are cost-competitive with what most radiator shops charge to repair a radiator, and there’s no delay. Just remove the old radiator and replace it with a new one.
Aftermarket replacement radiators are available in a wide variety of materials, designs and sizes. What’s important here is matching (or exceeding) the cooling performance of the original. Some replacement radiators provide improved cooling performance with additional rows of tubes, added thickness and/or a more efficient design.
For some applications, there may be an aluminum or copper/brass radiator available as a replacement option. There’s usually not a huge difference in price, so cooling performance and weight may be the main features to consider. Aluminum is typically lighter while copper has excellent heat transfer characteristics. However, the overall cooling performance of a replacement radiator will vary depending on its design and size.
The width, height and thickness of a new radiator should match that of the old radiator for ease of installation — unless the customer wants a larger radiator for improved cooling performance. The size and location of the hose connections and ATF cooler connections on the radiator (if used) must also be similar to those on the original radiator.
It’s also important to replace the radiator cap along with the radiator. Old radiator caps can leak pressure and cause an engine to overheat. A new thermostat should also be recommended, along with a new upper and lower radiator hose.
Your customer will also need antifreeze and water (distilled or deionized is recommended). A 50/50 mix of antifreeze and water is the standard recommendation for year-round freezing and boilover protection.