How to install the electric fan on the radiator?

To install a new electric fan on a factory or aftermarket radiator that does not have a fan installed already, it’s not as easy as some people think.

The reason is because of how the engine and cooling system are designed. If you have an aluminum factory radiator with fins on the tubes, there will be very little space to mount the fan, plus it’s hard to attach the mounting bolts. If you go with a universal radiator setup like me, then there’s more room and easier installation.

How to install an electric fan on the radiator – Fan Selection :

Selecting an electric cooling fan for your vehicle isn’t as easy as picking one off the shelf at AutoZone or Advance Auto Parts. You need to know how many square inches of the cooling area your radiator has and select a fan that will flow enough air through the radiator core. For example: If you have an aluminum 3-row radiator with 14 fins per inch, then your cooling area is approximately 350 square inches.

Installing an electric fan that has a maximum of 500 CFM static pressure will not provide enough airflow to do the job it’s intended for.

This fan provides about 800 CFM at only 8 pounds of static pressure which is perfect for this radiator setup.

Mounting Location :

I wanted my fans mounted on top of the radiator instead of hanging down from the grille or front bumper, so I came up with a simple mounting system using angle aluminum and body spacers.

This is what you’ll need: Two pieces 10″ X 3/8″ X 1/8″ angle aluminum Four-1/2″ X 1/2″ stainless steel bolts Four lock washers One piece 4″ X 8-1/2″ X 3/8″ spacer One piece 4-3/4″ X 8-1/2″ X 3/8″ spacer Drill Press

Drilling a 3/8 hole through the radiator support isn’t as easy as you think. You will need a drill press to properly align the holes and stabilize the angle iron so it doesn’t go crooked during drilling. With this complete assembly, I have mounted two fans onto my modified crossfire intake manifold for testing purposes only…

Fan Placement : 

To avoid your electric cooling fan from making contact with your belt or serpentine belt, you may have to relocate your alternator.

Here is the fan mounted under the crossfire intake manifold with a 5/8″ spacer between the fans for clearance.

As you can see, this fan assembly fits perfectly under the intake manifold and clears everything. This location also provides plenty of fresh air flow below deck level to keep everything nice and cool.

To find out your radiator’s cooling area, you must measure the height and width of the tubes in inches. You then multiply this number by 2-1/2″ to determine how many square inches of surface area there is.

For example: If your radiator’s tubes are 41″ high x 19″ wide = 907 square inches of surface area.


I have tried several different fans with this radiator setup and have found that 7 blade Flex-A-Lite 280 series fans work perfectly for me. I recommend these fans because they move some air at only 6 pounds of static pressure. Remember it all comes down to what YOU want so feel free to experiment with different setups.

Hope this article has been helpful and thanks for reading.

FAQs Section

Q1: What will you need to relocate if I go with a Flex-A-Lite fan?

A1: If your vehicle requires that the alternator be relocated, then you’ll need the brackets which are sold separately. The stock Chrysler alternator bracket may work on some applications, but not all. You may have to fabricate your custom relocation kit depending on what type of fan you purchase.

Q2: How do I know if my factory or aftermarket radiator will support an electric fan?

A2: Factory aluminum radiators usually provide plenty of room for the included high-performance (low profile) fans, but it’s rare when it comes to third-party replacement radiators.

Some 3rd party replacement aluminum radiators provide enough room for a Flex-A-Lite fan, but most of the time there isn’t any room at all.

If you plan on using a Flex-A-Lite fan then I recommend getting a Ford Modular Radiator from Ford Racing. It has been designed from the ground up to support an electric fan and provides plenty of room.

Q3: How do I know if my radiator will handle two high output fans?

A3: This depends on how much airflow your application requires. The more cooling area you have the better chance your radiator will handle the airflow without issue.

There are no specific rules or equations to figure this out since every application is different, but here’s some additional information that might help. Flex-A-Lite indicates that if your radiator is one row deep, it can handle two high output fans as long as you use a sandwich adapter between the fans and radiator.

For example: If your application requires 30″ of airflow and your radiator is 19″ wide (single row), then there should be enough room to mount the first fan on the engine side and the second fan on the passenger side of the radiator.

Q4: How large should I go with my electric cooling fan?

A4: Most Flex-A-Lite fans require very little current, but for those that need more than usual electrical system upgrades such as higher gauge wires or an onboard computer to control them, then consider going bigger because it’s more efficient.

For example: if your new fan(s) need 100 amps at 12 volts, you’ll need to upgrade to at least a 200 amp alternator or equivalent when utilizing an onboard computer system.

Adjustable speed controllers are less taxing on the electrical system when compared to solid-state full power controllers which require a more current draw. Since most Flex-A-Lite fans utilize very little current, it’s best to go with the highest airflow requirement possible for your application.

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