Radiator Fouling

The engine in your truck, tractor, or other vehicle might be running hot and you’re not quite sure why even though you’ve looked at the radiator.

Ray Bohacz is Successful Farming’s engineman. He says a lot of the questions he receives are related to cooling system issues. It may be because many people don’t understand how an engine is cooled.

"The misconception being that the radiator cools the engine. The radiator does not cool the engine. It is the liquid’s job, the antifreeze, to cool the engine, and it is the radiator’s job to cool the liquid," says Bohacz. "And to prove that this is correct, some of you may have a boat. Many boats use lake water or sea water and don’t have a radiator, so that proves that the radiator does not cool the engine, it’s the liquid that cools the engine."

There are many components to a radiator, including fins and tubes. The tubes carry the coolant and the fins touching them is where the heat dissipation occurs. When you’re doing an inspection, check for corrosion on the tubes which will limit the flow of the coolant.

He says the accumulation of deposits in the lower part of the tube can’t be seen from the fill point. Over time it blocks flow of the liquid and might diminish the effective size of the radiator. This is called “fouling.”

"It’s very easy to determine if you have radiator fouling, use an infrared gun with the engine hot to measure the temperature across the core," he says. "Contrary to what you would think, the cold part of the core is what is blocked because there is no hot flow going there."

 Learn more about radiator fouling and find more engine tips from Ray