Fan clutch acts up immediately after replacing radiator

[fred m]

Read the title. Coincidence? I replaced my radiator Saturday, due to a crack in the plastic tank. Drove it around and topped the coolant off, had no problems.

Truck sat and cooled off. Later that afternoon, I took a ~3 hour trip, highway at about 65mph, 20 miles in the fan clutch totally locks up. Sounds like a freight train the whole trip, and I got about 2 mpg less than normal. Sunday morning, driving around, the fan makes a lot of noise accelerating from stoplights, the clutch seems to free up once I'm past 40 mph or so. It acts the same today.

The fan clutch is a CARQUEST "severe duty" replacement with a lifetime warranty, has been on there for about a year/40k miles, and has functioned normally until Saturday. Never before heard a bit of noise from it, except the first 10 seconds or so after a cold start.

The radiator is a Spectra Premium, it replaced the original. Air seems to be flowing through it fine. Coolant temp stays solid between 195 and 200, has been that way forever.

I'm thinking cash in on the fan clutch warranty, and try my luck with a new one.
Thoughts?

Truck is an '02 3.0L/Auto

 

[RonD]

Yes, I would swap it out under warranty

Fan clutch gets its engage/disengage from the center of the radiator
It has a bi-metal spring on the front that expands when heat by center of radiator this slowly engages the fan to spin closer to engine/pulley speed

Yes, when cold the oil in the clutch is thick, so on start up fan is fully engaged, which as you said last for maybe 5 to 10 seconds, it then thins out and clutch is disengaged until spring starts to heat up

 

[cbxer55]

This time of year, with the high summer temps, I don't think the oil is that thick. I can go out now and spin the fan in both my Lightning and Ranger. They both spin with just a little resistance. Recently had the Lightning's fan off, was attempting to put on a efan (fan motor smoked out on first start up, so that's that on efans, never again). While off, I left it sit in the sun for a bit, still would spin with a little resistance. Out of curiosity I put it in my freezer over night. Next morning, it still would spin exactly the same. So is that fan bad? Truck's never overheated, and the temp gauge is always in the same spot, even with the ac on, except during winter when it sits a tad lower. Ranger's the exact same. Anytime I've opened the hood and spun the fan, there's never been any indication either ever locked up. Even after shutting it off on a 100+ day and had the ac on. Pop the hood, fan spins.

 

[RonD]

Reads like a bad fan clutch to me

But engine temp should go up when you come to a stop, after say driving on the highway, if the fan isn't moving enough air thru rad, if you don't get that symptoms then all is well.

Fans are only really used when driving slow and when stopped, which is why the e-fans are better for power(to the wheels) and MPG, both.
But as you said, not for every one, lol

 

[Bird76Mojo]

A bad fan clutch often leaks oil out of the front. It will collect dirt and be easy to see.

 

[wildbill23c]

Read the title. Coincidence? I replaced my radiator Saturday, due to a crack in the plastic tank. Drove it around and topped the coolant off, had no problems.

Truck sat and cooled off. Later that afternoon, I took a ~3 hour trip, highway at about 65mph, 20 miles in the fan clutch totally locks up. Sounds like a freight train the whole trip, and I got about 2 mpg less than normal. Sunday morning, driving around, the fan makes a lot of noise accelerating from stoplights, the clutch seems to free up once I'm past 40 mph or so. It acts the same today.

The fan clutch is a CARQUEST "severe duty" replacement with a lifetime warranty, has been on there for about a year/40k miles, and has functioned normally until Saturday. Never before heard a bit of noise from it, except the first 10 seconds or so after a cold start.

The radiator is a Spectra Premium, it replaced the original. Air seems to be flowing through it fine. Coolant temp stays solid between 195 and 200, has been that way forever.

I'm thinking cash in on the fan clutch warranty, and try my luck with a new one.
Thoughts?

Truck is an '02 3.0L/Auto

There's your answer highlighted for you. Its a heavy duty fan clutch it will always operate in a locked state far more than you'll find it unlocked, its severe duty for a reason, it works to keep everything cool it doesn't know you are just cruising around town, it don't care, it just really max cools all the time being the heavy duty version. I have the heavy duty clutch on my Bronco 2 as well, its locked up quite often during warmer weather, don't care, I would rather have the engine running cooler especially with the AC running too.

 

[cbxer55]

A bad fan clutch often leaks oil out of the front. It will collect dirt and be easy to see.

Yeah, it was dirty, 15 years old, to be expected. But no indication that it leaked any fluid. It cleaned up nice before I put it back in. Neither fan spins freely, there is some resistance. Just nothing heavy. The Lightning has two 2013/14 Mustang carbon fiber hood vents. When it's idling, you can feel the fan's air movement blowing hot air out them. I'm not worried. Thinking about whacking up the Ranger's hood and putting two of those in it's hood as well.

 

[8thTon]

This time of year, with the high summer temps, I don't think the oil is that thick. I can go out now and spin the fan in both my Lightning and Ranger. They both spin with just a little resistance. Recently had the Lightning's fan off, was attempting to put on a efan (fan motor smoked out on first start up, so that's that on efans, never again). While off, I left it sit in the sun for a bit, still would spin with a little resistance. Out of curiosity I put it in my freezer over night. Next morning, it still would spin exactly the same. So is that fan bad? Truck's never overheated, and the temp gauge is always in the same spot, even with the ac on, except during winter when it sits a tad lower. Ranger's the exact same. Anytime I've opened the hood and spun the fan, there's never been any indication either ever locked up. Even after shutting it off on a 100+ day and had the ac on. Pop the hood, fan spins.

If you never got it hot enough to activate the thermostat/bimetalic spring it would always spin about the same. The hydraulic fluid is there to keep the fan from spinning past a given rpm, and the clutch determines when it is hot enough to be driven in a low-slip mode.

Understanding Fan Clutches — and When it's Time to Replace Yours - OnAllCylinders

When you think of an automotive cooling system, the first thing that likely comes to mind is your radiator…or maybe your cooling fan. The oft-overlooked fan clutch doesn’t get a ton of credit …

www.onallcylinders.com

 

[88workcar]

I got my truck two months ago. The fan was loud from the start. Bad clutch, I went elec and saw the 2mpg gain also

 

[8thTon]

So then an electric fan is an improvement over a broken belt driven fan.

 

[RonD]

Actually an e-fan is better than a working or broken mechanical fan, not even an arguable point, mechanical fans are just cheaper for car makers, but more and more are switching to e-fans to get the better MPG numbers

 

[8thTon]

Actually an e-fan is better than a working or broken mechanical fan, not even an arguable point, mechanical fans are just cheaper for car makers, but more and more are switching to e-fans to get the better MPG numbers

Such are the claims, yet I see no data to back it up. E fans have been on the chespest cars made for decades, and they are not high cost items. I see claims of X mileage improvement based on one tank and compared to a failed clutch fan, or an aftermarket severeduty fan.

Meanwhile in a market where mileage numbers are hugely important to manufacturers, Ford put a clutch fan on the new Ranger. Look at all the equipment on that engine, all to get mileage numbers up, yet they needed the dollar or so difference for the fan?

Or maybe there are other considerations - like better cooling and that the mileage improvement isn’t very large?

 

[RonD]

Transverse mounted engine vehicles have no choice, which are the cheapest cars, lol.

Longitudinal mounted engines are where car makers have the choice, or DIYer

Adding a fan clutch and fan to existing water pump pulley is a no brainier and cheapest method

Adding electric motor(s), relay(s) wiring and maybe a larger alternator, simply costs more

Obviously MPG will be better, and power, if you eliminate a power draw on the crank pulley, thats why its not an arguable point, turn off AC and MPG gets better, much bigger difference, lol, but point is made

Radiator cooling fan only needs to be used for extra cooling, so draw on alternator by e-fan will not be all the time, like a mechanical fan, and thats the better MPG and power

As far as the new Ranger, I guess you would have to ask Ford, maybe with the 2.3l ecoboost and turbo an e-fan would have to be on most of the time for extra cooling, so benefit wouldn't be enough to off-set the expense of adding the e-fan
Or they max'ed out largest alternator already with all the electronics on that vehicle, lol, man there is alot

 

[8thTon]

The mechanical fan is not “on” all the time either. The viscous coupling prevents it from using any more than a fixed amount of power, and the thermostatic clutch lets it idle if not needed.

Also, tests of how much power they use on a dyno when not being driven would not be valid - when the truck is moving airflow through the radiator will help rotate the fan.

Last, the engine has more power turn the fan when it is needed than an electric motor.

 

[RonD]

You are right, mechanical fan is not "on" all the time, its only "on" then engine is running, lol, joking

Yes, fan clutch will allow fan to spin with air flow through radiator as vehicle speeds increase but its still a draw on the engine, because its a fluid coupling, less of a draw but still a draw

e-fan would be shut off at that time, so 0 draw

mechanical fan draws maybe 3hp when fully locked, but probably average 1hp

e-fans are all under 1/2hp, usually .3hp, but you really don't need more than that, if you do then you have cooling system problems not fan problems, and more HP won't help

So mechanical fan is just less efficient than e-fan HP wise