About Classic Car Radiators

The radiator has been around for a long time. Many credit the invention to Franz San Galli. He received a patent for the device in 1857. In automotive applications they constructed these heat exchangers from brass and copper from the early 1900s all the way through the 1970s.

In the mid-70s aluminum started making its way onto the playing field. Eventually it was adopted to replace the more expensive copper and brass metals. Finally, automotive manufacturers started producing aluminum radiators with plastic header tanks.

Not only did this lower the costs per vehicle, but also reduced the weight of the large part. When attempting to make a decision on whether to repair or replace a classic car's radiator, knowing what material the current part consists of becomes important. Brass and copper when in good condition is reliably repaired by brazing and welding. Aluminum on the other hand is extremely difficult to fix. Repaired aluminum radiators often become unreliable and are better suited for replacement.

Diagnosing Radiator Problems

Before you can make an educated decision on whether to repair or replace the radiator, you need to find out what the problem is and the extent of damage. Overheating and coolant leaks are the two most common complaints when it comes to the failure of an automobile radiator.

Although not as common as a leak, engine overheating caused by the reduced cooling capabilities of a blocked radiator is often created by humans. This is especially true for vintage automobiles. These vehicles can pass through the hands of many owners, leaving radiator repair history unknown.

It's not uncommon for the seller to install radiator stop leak before the car is listed for sale. This can stop a leak problem, but create an overheating issue. There is another quick repair to look out for on classic cars. When a single tube or core is leaking the weak spots can be pinched off to prevent water from flowing through the leaking area. This again, can solve the problem for a quick sale, but lead to a hard to find overheating condition. An excellent technique for finding these kinds of problems is using an infrared temperature probe. Focus the red beam of light in different places on the radiator cores and then inspect the cold spots for blockage.

When it comes to leak checking a radiator the best results are obtained by applying even pressure to the header tanks and cores. A simple device called a coolant pressure tester is installed in place of the radiator cap. A hand pump is then operated to apply pressure to the entire cooling system. A tool mounted pressure gauge is then monitored to verify the pressure is holding and not slowly leaking down, which would indicate a leak. Another tool used in conjunction with a coolant pressure tester is the human eye. A careful visual inspection of the radiator and its cores can reveal problem spots. Areas with green or white powdery deposits are the telltale sign of past or present problems.

Making the Repair or Replace Decision

Making the decision to repair or replace the vehicle's radiator is a personal decision. Some classic car owners place a lot of value on retaining original equipment parts. Other owners might place more importance on having the vehicle repaired in the shortest length of time. No matter what side you fall on both methods are fully supported by specialized companies that can rebuild, re-core or repair your current radiator. There are also reliable classic car parts suppliers that pride themselves on providing direct replacement radiators that resemble the original equipment in every detail.

With that said, there are some best practices that should be followed. After performing the inspections as outlined above, radiators with multiple blockages or leaking areas should be replaced in some situations. As an example, if you look at a classic Chevrolet from 1970 likethe first generation Monte Carlo, the radiator is barely visible. It's covered by a pickle barrel shroud on the engine compartment side and a plastic cover over the top. Even the strictest car show judges won't deduct points when a replacement radiator is selected in this situation. However, on many vintage automobiles the radiator is highly visible and can become a focal point in the engine compartment. In these situations repairing the original part might make more sense.