Your cooling system would be nothing without your fan clutch, a part most people aren’t even aware of. A fan clutch controls the air flow and temperature of the engine, and specifically prevents it from overheating. This is crucial because if the engine overheats this can cause serious problems and even force the entire machine to shut down. That’s the last thing anyone wants to happen to their equipment. Learning about the different parts of your machinery will prepare you for possible scenarios so you can act quickly when problems do arise and get back to work.
Different Types of Fan Clutches
The fan clutch operates based on temperature to ensure it isn’t running all the time and wasting your equipment’s energy. When the engine is cool due to the vehicle’s speed forcing air through it, the fan clutch turns off. Alternatively, when the engine gets hot, or the vehicle isn’t moving fast enough, the fan clutch turns on to protect it from overheating. All fan clutches should do this if they’re working properly, but that doesn’t mean all fan clutches are the same. Here are the three main types of fan clutches to determine which one you have or need to invest in:
Non-thermal Fan Clutch
A non-thermal fan clutch is RPM (revolutions per minute) dependent. It relies on force from the shaft of the water pump to determine when it needs to turn on. For example, when your vehicle is moving quickly it’s at a high RPM. This force closes the valves and keeps the energy transferring fluids in their valves, stopping the fan. The increased speed provides a steady flow of cooling air and lowers unnecessary fuel usage. Conversely, when the vehicle is at rest the valves open and the fluid provides the force that turns the fan on, keeping your engine cool without any outside air.
Thermal Fan Clutch
A thermal fan clutch relies on temperature to turn the fan on and off. This is achieved by using a bi-metallic spring that senses the engine’s temperature. When the engine heats up, so does the spring at the front of the clutch. The mechanism turns and opens valve ports, releasing silicone fluid to engage the fan. Once the temperature cools down the spring uncoils and closes the valve ports, shutting the fan off.
Electronic Fan Clutch
An electronic clutch works the same way as a thermal one, but instead of relying on changing temperature it relies on the vehicle’s computer. More specifically the clutch relies on the Engine Control Module (ECM) or Powertrain Control Module (PCM) to correctly analyze the coolant temperature, intake manifold temperature, transmission oil temperature, A/C pressure, and engine oil temperature. These variables will be determined by your vehicle’s manufacturer specifications. Once your vehicle’s computer senses that you are exceeding temperatures and pressure limits, it will signal the clutch’s valves to open and efficiently cool your engine.
Signs to Watch Out For
While knowing how your fan clutch is supposed to operate helps you understand your vehicle and improve its efficiency, you also need to look out for signs of failure. The more aware you are of the possible issues the more likely you are to catch a breaking part before it do some serious damage.
The most obvious sign of a faulty fan clutch is overheating. Regardless of if the clutch is partially working or not working at all, both scenarios decrease your cooling system’s ability to do its job. You will likely be able to feel the difference in the heat radiating from your engine and notice the lack of temperature change between when you are moving and when you are not.
If your fans have become louder, that could also be a sign that something is wrong. Most likely the fan clutch has gotten stuck, leaving the fan permanently engaged whether you’re moving or not. This will be extremely noisy, and you will notice it persists even after you’ve come to a full stop.
Has your vehicle lost some of its power, struggled to accelerate, or used more fuel than usual? Your fan clutch might be to blame. Typically accompanied by a loud fan, the stuck clutch will cause a drag in the engine, slowing down its normal functions and affecting your vehicle’s entire performance. Do not ignore any of these symptoms or dismiss the fan clutch as the cause. Checking this and other parts of your machine on a regular basis can help prevent bigger problems from arising and killing your machine.
Is it Time to Replace Your Fan Clutch?
For an often-overlooked part, the fan clutch is a vital piece of any cooling system. It senses the change in temperature and activates or deactivates the engine’s fan to maintain ideal conditions. If it gets stuck or stops working altogether your engine and vehicle are put in immediate danger of overheating and taking severe damage if action isn’t taken quickly. ACTParts provides a wide selection of cooling system components, including aftermarket fan clutches. Contact us today to find the best parts to keep your engine cool and safe from the heat.