The biggest advantage to flex fans is their ability to pull more air through the radiator at an idle than a clutch-operated fan. … The flex fan aids in idle or slow speed operation, however, they rob more horsepower than any other style of a fan at high RPMs. They are also particularly noisy at low RPM.

How much horsepower does a flex fan take?

I’m sure a flex fan takes 5-10 horse but some large electric fans can pull 30 amps. Might be a horse or two just to make that. For the money you can’t go wrong with a standard thermal coupled mechanical fan and a proper shroud.

Why is clutch fan bad?

A stuck fan clutch will cause excessive, unnecessary drag on the engine, which can cause a drop in power, acceleration, and fuel efficiency, sometimes to a quite noticeable degree. As the fan clutch is one of the main cooling system components, it is very important to the proper operation of the engine.

Is a clutch fan better than a regular fan?

When compared to an electric fan, fan clutches are quite inefficient. … The benefits of a Thermatic Fan lay in its ability to provide constant air flow, improved fuel economy, better air-conditioning performance, cooler engine running and increased engine power.

Is a fan clutch necessary?

The fan clutch is one of the most essential components in the operation of cooling fans and greatly contributes to the overall operation of the engine. While many new vehicles use electric cooling fans, many older vehicles utilize a mechanical fan clutch to help control the fans.

What is the advantage of a flex fan?

The biggest advantage to flex fans is their ability to pull more air through the radiator at an idle than a clutch-operated fan. This is particularly useful on engines running high compression ratios that are more difficult to cool.

How much horsepower do you gain with electric fan?

In a normal pickup situation, even in high ambient temperatures, the electric fan system will only draw a maximum of about 5 horsepower from the engine. This significant savings improves fuel economy, and, in turn, reduces emissions while improving vehicle performance.

Are mechanical fans better than electric fans?

Electric fans rely on electric energy from the battery and charging system. But in cooling, what makes a good fan is optimum airflow for cooling with minimum energy consumption (for maximum engine power and fuel economy). An electric fan completely removes the mechanical load of spinning the fan from the engine.

What's the difference between thermal and non thermal fan clutch?

Non-thermal clutches operate solely based on the shaft speed of the water pump. … A non-thermal clutch provides a steady flow of cooling air but is always engaged, so it offers lower fuel savings than a thermal-style fan clutch. However, non-thermal clutches are a lower-cost option than thermal-style clutches.

Can a fan clutch cause overheating?

Overheating engine is the most common symptom of a bad or failing fan clutch. It controls the operation of the cooling fans. These cooling fans will disable/not work at maximum efficiency as the bad clutch will not engage properly. This result in overheating which may lead to serious issues if not timely attended.

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How much does it cost to replace a fan clutch?

Repair TypeZipCostClutch Fan37475$384Clutch Fan13369$224Clutch Fan98027$179Clutch Fan7767$352

How stiff should a fan clutch be?

There should be a nice, consistent, deliberate rotating force such that when you let the fan go, it should start spinning back up at a rather rapid rate of rotation. If right after you release the fan to spin, and the fan spins ever so slowly, then your fan clutch isn’t working right.

When should a fan clutch engage?

Answer: Most fan clutches engage at about 170°F air temperature (about 180-190°F engine temperature). They reduce the temperature about 20°F before disengaging.

How do you diagnose a bad fan clutch?

To confirm the diagnosis, start with this simple test: Spin the fan as hard as you can on an engine that has not been started that day. If the fan rotates more than five times, you can bet the clutch is bad. You should feel some resistance and the fan may spin up to three times, depending on the ambient temperature.

Do electric fans make a difference?

Although they will place an additional draw on the electrical system, they are a more efficient alternative to mechanical fans and don’t cause the dreaded parasitic horsepower loss. Here are a few other advantages of electric fans: Consistent cooling—they maintain their airflow at all times. Reduced water pump wear.

How many watts does a electric fan use?

FIXTURE / EQUIPMENTWATTAGEESTIMATED kWhr USE MONTHLYAirconditioning Unit (2.0 HP)1,913688.68Desk Fan 10″5012.0Desk Fan 12″358.40Desk Fan 14″555.40

How many amps does radiator fan draw?

Twelve- to 16-inch fans can draw from 15 to 28 amps, while some dual fan applications can draw up to 35 amps. Make sure your electrical system can handle the addition of an electric fan.

What size cooling fan do I need?

As a general rule of thumb, follow these minimum cubic feet per minute (cfm) ratings when using an electric fan as the primary cooling source on a basic engine: 1,250 cfm for a 4-cylinder. 2,000 cfm for a 6-cylinder. 2,500 cfm for a 8-cylinder.

What is the difference between a heavy duty and severe duty fan clutch?

A Heavy Duty fan clutch will lock up 70 to 80 percent when engaged. A Severe Duty fan clutch will lock up 80 to 90 percent when engaged. … The PCM typically monitors the following parameters; AC demand, transmission temperature, engine temperature, fan speed, and AC head/high side pressure.

Can you drive with a bad fan clutch?

A failing fan clutch can actually cause the engine fan to become loose and wobble. Sometimes this wobble can be heard while driving, especially at freeway speeds. You can turn on your car’s engine while the vehicle is in park or neutral, pop the hood, and see for yourself that the fan is wobbling as it spins.

Will a bad fan clutch cause AC problems?

Registered. Yes, a bad fan clutch will cause A/C issues. The condenser needs air flow to cool hot refrigerant.

Are Flex fans good?

For high rpm use, flex fans are considered an upgrade over clutch fans. They can be a good choice for modified vehicles turning 6,000 – 8,000 rpm. Advantages include: They move more air for better cooling.

How much air does a clutch fan move?

The clutch fan assembly is said to move as much as 5000 CFMs at high temp and RPM, but of course with more airflow comes greater drag. There is no doubt that the clutch fan assembly moves more air than any other setup, but to some the pros of an efan setup may outweigh the cons.

What is a hydraulic fan?

A hydraulic fan drive system allows variable fan speed independent of the engine speed. It provides only the cooling that is required throughout the operating range of the vehicle including such requirements as the maximum engine rated torque point where high cooling may be required at lower than maximum engine speed.

Why is my clutch fan so loud?

A roaring noise could mean a number of things, including a bad wheel bearing, worn tires, or a differential that’s low on oil. Often times, it’s the fan clutch. When the clutch shoe inside the part gets stuck, it fails to disengage. … This causes the roaring noise.

Why does my engine sound like a fan when I accelerate?

It is possible that your engine is getting hotter than normal and is kicking the fan on harder to assist with cooling. It is likely that if the issue got any worse that a warning light may come on. … Another possibility is that the fan motor is starting to fail and causing noise while the fan is running.

Does a fan clutch squeal?

Sometimes the fan clutch in your car will start making squeaking and squealing noises. … A noisy fan clutch can also be the culprit when your car is overheating.

How expensive is it to replace a water pump?

The average water pump replacement cost is $550, with prices ranging from $461 to $638 in the US in 2020. But typically depends on the type of vehicle you drive and the auto repair shop you take it to. Labor costs are between $256 and $324 while parts cost between $205 and $314.

Does a clutch fan spin all the time?

Fan Clutch Types A small amount of resistance always keeps the fan spinning, but it’s basically free-wheeling until the fan clutch engages. When the fan clutch engages, it spins up greatly, increasing air flow through the radiator and over the engine.

Should a fan clutch be hard to turn?

It is normal for it to always be turning. However, the clutch should not engage it fully until it has hit the right temp. On mine, it is very clear when the clutch has fully engaged the fan as it sounds like a turbine.

How should a fan clutch work?

A fan clutch is a thermostatic engine cooling fan that can freewheel at low temperatures when cooling is not needed, allowing the engine to warm up faster, relieving unnecessary load on the engine. As temperatures increase, the clutch engages so that the fan is driven by engine power and moves air to cool the engine.