Radiator Cooling Fans

A radiator fan, also known as a cooling fan, is a type of fan that is used in automobiles to keep the radiator cool. It is a device that moves air through the core of the radiator to create a cooling effect. Radiator fans are typically a set of blades attached to a hub. The assembly can be made entirely of metal or plastic. Because it helps lower the engine temperature, the radiator fan is one of the parts that make up a vehicle's cooling system. The fan is mounted just behind the grille, in front of the radiator, or behind the radiator. The fan may be electric or mechanical.

Blown fuse: As with many of your car’s electrically-powered systems, the radiator fan circuit incorporates a fuse. This fuse will blow in the event that its circuit is overloaded, shorts out, or has some other problem.

Bad relay: The radiator fan relay controls the delivery of power to the fan itself. The relay is an electromagnetic switch that controls the power supply to the engine’s cooling fans. A bad relay will prevent the fan from working properly.

Low Coolant Levels: If your car’s coolant gets too low, there will not be enough coolant in your cooling system to properly remove the heat produced by your engine. The coolant temperature sensor will not read the coolant temperature correctly

Bad sensor: If the temperature sensor is faulty, the control unit doesn’t interact with the radiator correctly. , the fan will not turn on to cool your engine when it should.

Bad fan components: What this means is that a problem with the fan itself can involve: The motor on an electrically-powered fan; The fan belt on an older vehicle;

Wiring Problem:  Any damaged, broken, or disconnected wiring can keep your radiator fan from working.

1. Turn on the air conditioner. Both fans should run as long as the air conditioner is on.
2. Hotwire the fan. Disconnect the electrical connector on the fan. Use two jumper wires to connect the two terminals to the positive and negative terminals on the battery. It should run if it is good.
3. Check the fuse.
4. Check the relay. Pull the relay and jumper the switch side of the relay and it should audibly "click" when it activates.
5. Check electrical connections for looseness or corrosion.
6. Check coolant temperature sensor.

Factors Affecting Radiator Fan Operation

1. Engine temperature: During engine operation, when the engine temperature exceeds the predetermined threshold, the fan will engage to help cool the radiator and bring the engine back to its optimum operating temperature.
2. A/C activation: The radiator fan can also be activated when the air conditioning (A/C) system is turned on. If you want to turn on the radiator fan manually, you can try it.
3. Vehicle speed: At low speeds or when idling, the airflow through the radiator may not be sufficient to cool the engine. In such cases, the fan is activated to compensate for the lack of natural airflow.

Determine your needs

1. Select Push or Pull Type

Push-type fans mount on the front of the radiator and blow air through the radiator core. Pull-style fans mount behind the radiator and draw air through the core.  When a vehicle is moving, a push fan can obstruct airflow due to its position in front of the radiator. A pull fan is more efficient because it mounts on the back of the radiator, pulls air through, and does not block airflow.

2. Determine diameter

You want a fan that covers as much of the radiator core as possible. Larger fans will allow your car to idle in the heat for longer periods of time without overheating.

3. Straight or curved blades

Straight blades move more air but are noisy. It all depends on your application, but curved blades are quieter but don't move as much air.

4. Determine optimum airflow

The more power your motor produces, the higher the airflow you want, follow this general guideline:

1,250 CFM for a 4-cylinder

2,000 CFM for a 6-cylinder

2,500 CFM for an 8-cylinder

5. Single or dual fans

If you have added a much larger engine or are making a lot of horsepower, you may want dual fans to maximize the amount of airflow.