C500 – Kenworth Side hood Louvers

C500 Kenworth Side Hood Louvers In an earlier article we talked about the Kenworth C500 truck itself and its magnificence. Let’s take some time now to talk about a common C500 modification misconception that adversely impacts the longevity of the truck – removing the side hood louvers. The butterfly hood on the Kenworth C500 has side hood louvers for cooling purposes. In our experience with dealing and servicing these trucks, we have seen almost 80% of them with removed side hood louvers. This is a very serious engineering design misconception and a highly impactful modification on the life of the truck.

It is very important to understand the necessity of these louvers from an engineering perspective. These louvers exist to create a good air flow pattern to keep the complete engine block at nominal working temperatures whilst hauling heavy loads. The fan works to pull the cold air in over the rad and the complete engine and create an air pattern that reaches all the way in the back of the engine block. A lot of truckers have this misconception that removing these side hood louvers cools down the engine further – especially when carrying over-sized loads. Honestly, this couldn’t be further away from the truth. You see, the placement of the temperature sensor under the hood can be misleading for many truck owners. When you remove the hood, the temperature sensor for the coolant is placed right off of the thermostat housing which in turn is placed right in the side of the engine towards the front, and it reads a lower temperature when you take off the side hood louvers. The temperature gauge for the coolant drops and you assume that the engine cooling is better with the side hood louvers off. This temperature reading in reality is erroneous, because it is tricking you in thinking that the complete engine temperature is lower.

In reality, you are actually baking the back part of the engine. Cylinders #5 and #6 are completely overheated and baking, especially when carrying heavy loads. Therefore, the side hood louvers MUST stay on, no questions asked. The only reason you remove them is for servicing purposes.