new fan clutch and fan or electric fan mod??

[aha2988]

I've run both a clutch fan and efan in many vehicles over the years. I prefer the efan as for 90% of what I do it works the best. While the flow is less than a mechanical fan the amount of power it draws is a lot less and it's not a constant draw like the mechancial fan. I'd be interested if you MPG is slightly better.

In the past I've just cobbed OEM fans to the radiators and run a stant coolant sensor kit.

havent ran the numbers yet; however, i reset the average gauge in the truck. before the mod i was averaging 14.3 on 33" tires 3" lift after the mod im averaging 17.1 on 33" tires 3" lift. There was also a carbon filter delete between gauge resets. I can't say its exactly acurate but i'll run the numbers on a full tank and repost what i find!! I won't know if im flowing enough air until mid july probably but the controller i bought has an extra wire to run a secondary fan so worst case i just have to buy an extra fan eather a pusher or a secondary puller. The flow feels sufficient though you can certainly feel air being pulled through the front condensor!!

 

[Sungod]

havent ran the numbers yet; however, i reset the average gauge in the truck. before the mod i was averaging 14.3 on 33" tires 3" lift after the mod im averaging 17.1 on 33" tires 3" lift. There was also a carbon filter delete between gauge resets. I can't say its exactly acurate but i'll run the numbers on a full tank and repost what i find!! I won't know if im flowing enough air until mid july probably but the controller i bought has an extra wire to run a secondary fan so worst case i just have to buy an extra fan eather a pusher or a secondary puller. The flow feels sufficient though you can certainly feel air being pulled through the front condensor!!

That fan looks small. Good luck when it gets hot. There is no way you gained 3mpg with an electric fan. That is impossible.

 

[aha2988]

That fan looks small. Good luck when it gets hot. There is no way you gained 3mpg with an electric fan. That is impossible.

plain and simple a clutch fan takes machanical force to run (i.e uses a great deal of power from the engine.) My fan clutch has been bad for a while so it was running continuously. always draining power from the engine. Saying my average increased by three mpg isn't saying my overall mpg's changed theres probably moments im still getting about 10 and thers times were im getting 22-23 its just an average reading. like I said im not sure if it will be enough fan until it heats up this summer. i do know that we ran the truck for about a 1/2 hour idling in the garage with the door open and the radiator temp never got over 140 which is about the mid gauge reading on your dash. when we turned the fan on it stayed right around 120-140 running at 2000 rpm for 20 minutes at 75 degrees room temperature. then drove 15 miles to cookout sat in line for 5 to 10 minutes then drove 15 miles back home (i live out in the country) checked the temp again it still wasnt over 160 and the thermostate wasn't even calling for the fan to come on it was only running because my A/C was on. I feel it works great and im curious to understand your concern If electric fans didnt work then im sure that those dragsters running huge V8 engines wouldnt use them to keep there engines cool, rock crawling buggies wouldnt have rear mount radiators with dual fans, 4wheelers, motorcylces, Electric fans obviously work and theres obviously fans out there with enough CFM output to keep any engine running cool. but i guess haters will always hate on good ****!!

 

[Sungod]

plain and simple a clutch fan takes machanical force to run (i.e uses a great deal of power from the engine.) My fan clutch has been bad for a while so it was running continuously. always draining power from the engine. Saying my average increased by three mpg isn't saying my overall mpg's changed theres probably moments im still getting about 10 and thers times were im getting 22-23 its just an average reading. like I said im not sure if it will be enough fan until it heats up this summer. i do know that we ran the truck for about a 1/2 hour idling in the garage with the door open and the radiator temp never got over 140 which is about the mid gauge reading on your dash. when we turned the fan on it stayed right around 120-140 running at 2000 rpm for 20 minutes at 75 degrees room temperature. then drove 15 miles to cookout sat in line for 5 to 10 minutes then drove 15 miles back home (i live out in the country) checked the temp again it still wasnt over 160 and the thermostate wasn't even calling for the fan to come on it was only running because my A/C was on. I feel it works great and im curious to understand your concern If electric fans didnt work then im sure that those dragsters running huge V8 engines wouldnt use them to keep there engines cool, rock crawling buggies wouldnt have rear mount radiators with dual fans, 4wheelers, motorcylces, Electric fans obviously work and theres obviously fans out there with enough CFM output to keep any engine running cool. but i guess haters will always hate on good ****!!

There are some very simple principles that can't be over looked. Energy cannot be created or destroyed. Your electric fan needs energy to run just as a mechanical one does. While there are specific situations where an electric fan will work, but those are niche situations at best. For a daily driver they are not ideal. They just do not push enough air. There is a reason that they are smaller, it is because in order to push as much air as the mechanical fan the motor would be huge and require a substantial amount of power.

A properly working clutch fan is a better option for a DD. It works like a thermostat that spins more as the temp increases. This means that on a cold day your fan is not sapping power, and sitting in traffic, although turning slowly, it is still drawing more air over a wider area than an electric fan is capable of.

In comparing my first-hand experience with electric fans I noticed zero change in MPGs, it ran hotter in stop and go traffic during the summer months, and was more hassle than anything. I am not trying to rain on your parade. I understand your excitement of your new mod, and I was excited when I did mine. I am just sharing my long term experience with it.

 

[aha2988]

There are some very simple principles that can't be over looked. Energy cannot be created or destroyed. Your electric fan needs energy to run just as a mechanical one does. While there are specific situations where an electric fan will work, but those are niche situations at best. For a daily driver they are not ideal. They just do not push enough air. There is a reason that they are smaller, it is because in order to push as much air as the mechanical fan the motor would be huge and require a substantial amount of power.

A properly working clutch fan is a better option for a DD. It works like a thermostat that spins more as the temp increases. This means that on a cold day your fan is not sapping power, and sitting in traffic, although turning slowly, it is still drawing more air over a wider area than an electric fan is capable of.

In comparing my first-hand experience with electric fans I noticed zero change in MPGs, it ran hotter in stop and go traffic during the summer months, and was more hassle than anything. I am not trying to rain on your parade. I understand your excitement of your new mod, and I was excited when I did mine. I am just sharing my long term experience with it.

I understand engegy can not be created nor destroyed Mr. newton however force times distance equals work my friend the drive belt travels a certain distance every time it makes one rotation durring that rotation you have many forces applied the idler pully bearing friction, the power steering pump, the a/c clutch drive, the water pump, the idler tensioner pully bearing friction, the altenator, and with a fan clutch you have the force of the fan blades pushing against the air grabing it and moving it. Now once you remove the clutch fan you signifigantly reduce the work required to turn the belt which was already turning an altenator which was aready suppying the battery with 12 volts and enough amps to supply all of my accessories plus the other accessories like air ride suspension that were optional on my truck but i do not have so instead of having energy (which cannot be created or destoyed) just sitting in my battery waiting for me to plug in an air mattress pump or something similar i pulled a small 25 amp draw to run a fan which has its own motor providing its own work from just a small 25 amp draw off of a continiously charging battery that was already supplied with plenty of power now yes it is a additional draw off the battery and the altenator might have to kick on more often over the same period of time but i've still greatly reduced the work required from the engine to drive the drive belt which in turn frees up horsepower and torque to the ground which allows more energy to move the vehicle instead of rotating a fan. I have not created nor destroyed any energy by removing my clutch fan you are correct sir; instead, I took energy being applied in one area and aloud it to be applied in another area. simple physics

 

[BCfish]

Hey Sungod we all understand you don't like the electric fan and that's fine we can all have our own opinions on this..But seriously you are beating a dead horse he's done the switch let's see what his results are over time that will tell the truth.

 

[450exc115]

Now things are starting to get good.

Something to consider. 100% of FWD vehicles have electric fans. So sized properly the difference in temp from an electric to mechancial fan should be no change. As for MPG and power, centrifical fans are a huge power hog and I'm willing to bet that the total efficency is very low with all the losses maybe 25-30% of power in is turned to air moving. Most electric motors are 80%+ efficent and even the fan should be 70% or more, this should yeild a total in the 40% range, if you add in the alternator being 80+eff then maybe get to the mid to high 30% range so you gain 10% on the XXhp that the fan uses. Second point is if the fan is intermitent then the power needed is less as a clutch fan is always spining and using power. I was thinking he may see 1mpg gain from it but 3 seems a bit high. maybe I need to delete the charcoal filter myself and see if I gain anything.

So the next agurement that I see is... I toyota could gain 1mpg from using electric fans why didn't they? Probably cost. The assembly, wiring, complexity during assembly probably cost more than a few bolts of a clutch fan and the cost to source a clutch fan. But that is just my opinion.

 

[450exc115]

Just consider the Prius (what an ugly car) is 100% electric. Electric power steering and Electric power AC. Why, electric motors are very good at converting energy to power. A perminent magnet motor (with rare earth magnets) can get up to 93% eff. The controller of a brushless PM motors run in the 95-97% eff range. I use to test and validate electric powered turbo machinery and our steady state design points were always 45-55% total power efficency which is 10-20% above the industry standard.

 

[aha2988]

I would def. stand behind removing the filter paper in the factory airbox, recently i did an internal snorkel mod that pulls air from inside the vehicle and at that time removed the carbon filter. I noticed a small difference in mpgs gains then. It was just happen stance that the next weekend my fan blade broke an i opted to put the electric fan in place. Having noticed even more gains in mpg i would recomend this mod i cant say its worth just going and changing what you have already but if your plastic fan blade breaks it will certainly save you money to switch over its probably not a bad idea for the more serious offroader. Just being able to turn the fan off in mud and water and prevent debree from being slung all around your engine bay is a plus not to mention cooler temps idling through trails (or jumping through trails :driving I talked to a ton of people about it and asked on this thread and received about a 50 50 response some people love them some people hate them due to bad experiences. all i can say is the worst thing about an electric fan is that it has the ability to not turn on. With wiring running through elements and extreme conditions i would imagine such assemblies do have a higher failure rate if not wired and installed properly. My clutch fan went out because i took the vehicle through some serious mud at a mud bog competition just fried the bearings in it so personly in my conditions a clutch fan has an extremely low eff. rating. I'd be currious to know why toyota choose the method of moving air they did myself. I'm sure they know how much CFM is required in higher temps to bad they wont list that info somewhere i can find it lol. I would think having that info would make it a no brainer build an electric fan with a eff. motor that moves the same air as a clutch fan. It would certainly be a bit more labor durring assembly so maybe production times do out way energy eff. percentages for toyota who knows. I'll be sure to post up over time what effects I find after running through the summer months when i installed this fan i noticed the radiator has plenty of mountable room for an addition fan the same size if i off center the them, and still allow the use of the same fan shroud which is awesome so im confident if this one fan proves insufficient I'll certainly be capable of creating more airflow if need be. thanks for all the input guys ill let ya know what i figure out...

 

[IOPturbo]

Thanks for posting the pics. I'm looking forward to doing this myself, electrics work you just have to source the right parts.

 

[aha2988]

Thanks for posting the pics. I'm looking forward to doing this myself, electrics work you just have to source the right parts.

awesome yo, you should post up any products you source and use when you get to it, see if we can find the best replacement for these things!!

 

[Sungod]

awesome yo,

I am going to make the stereotypical assumption that you are young with your choice of vernacular. Along with being young comes lack of experience. You seem to be confusing the topic. Your fan is small. It will only draw a small amount of air compared to your stock fan. It won't have the power or the capacity to cool as your mechanical fan does. In realistic terms your fan mechanical or electric only work at low or no speed. In that sense obviously a mechanical fan will be less efficient. It is speced to cool to a specific temp at a certain RPM. The mechanical clutch fan runs at engine speed, but does not always run. This is a big difference between old style direct connect fans that you would see in a 72 Nova. Those designs clearly wasted energy. A clutch fan is different. It only runs as needed and at speed, it will turn freely using no energy at all. That is means that most of the time you are driving it will make no difference.

So your assertion that an efan is more efficient is correct, but not substantially. Obviously either fan requires energy to run and your engine isn't just turning out free energy. The reality of the change is minimal at best and if you do a lot of highway driving and in winter, it could be zero.

So discounting those gains are notable on electrical vs. mechanical, let's look at your set up. As stated, your fan is small. It looks like it may cover half of what your mechanical fan covered. The problem you will run into on a hot day is that you are now only drawing air over a small portion of your radiator. That along with a reduced volume means you have less opportunity to release that heat and it goes back into your block. While it is true that some, but not all FWD cars have electric fans, those fans are designed for that vehicle and that particular radiator. They fit in a shroud that covers the entire radiator and yours does not.

Another area of concern is reliability. A mechanical fan will always turn unless the belt driving it breaks and when that happens you will know it. An aftermarket efan can stop working and you will have no idea unless you are watching your temp gauge.

I am not knocking the fan. I think they are good in their applications. I am sharing my view as someone who has used them, but see that their value is not worth the risk and the hassle.

 

[aha2988]

first let me state that the pictures clearly show that the fan I chose is only 1in smaller in diameter than oem still utilizes stock shroud directing flow accordingly. second the fan I chose has an additional fan blade compared to oem
( do you even know the cfm rating required for these trucks that would be helpful to this thread!!) third me having a BSME I would always plan for the worst I personly wired in a test light to a switch so at any time durring driving I can check the operation of the fan by a.) turning the manual fan switch on and pushing the test light button b.) turning the a/c on and pushing the test light button or c.) allowing the radiator temps to heat enough to activate the termostate switch and pushing the test light button. thirdly if the summer weather proves to be to much I have an additional fan power wire on the controller to run any other fan I need. im sorry u had a bad experience with your efans but I have seen significant improvements in throttle response mpg's as well as smoother idling and cooler tempts. I'm done arguing at this point I've already made the switch I will certainly post positive or negative reviews of my selection but as of the past 150 miles I've truly injoyed it

 

[Gerdo]

FYI The electric fan replacement for a 3rd gen, 3.4L, is 3600cfm.
I'm not sure how a 1500cfm is going to do when wheeling or slow driving in the heat of the summer.

 

[aha2988]

FYI The electric fan replacement for a 3rd gen, 3.4L, is 3600cfm.
I'm not sure how a 1500cfm is going to do when wheeling or slow driving in the heat of the summer.

Thanks for the info I wasn't ever able to fine any numbers I basicly just bought the biggest fan I could find at a parts store I'll def find out this summer hopefully at worst I'll just need a second fan. or look harder for a nice one who knows my main problem was needing to get the old fan and clutch out cuz they went bad on me so far this fan has been plenty but our high for yesterday was 70 lol

 

[450exc115]

You want to remove the fan shroud from the mechanical fan, it should help with low speed flow and if you need a larger fan it will give you a larger area to work with.

This is a big difference between old style direct connect fans that you would see in a 72 Nova. Those designs clearly wasted energy. A clutch fan is different. It only runs as needed and at speed, it will turn freely using no energy at all. That is means that most of the time you are driving it will make no difference.

I'm goint to have to disagree with you on this one. The new fans always spin and take power to do it. While not drawing full power they take some. I'll also argue on reliablity of OEM fans too as you don't see cars on the side of the road overheated all the time so I feel the reliablity is very high.

If you want to argue that his setup is probably not that robust and may not be properly sized I'm ok with that but to sat a Efan vrs a mechaincal is a bad idea I won't agree with you and would agrue against you.

Just for the rest of the crowd reading this most vehicle have two efans. One that runs off a temperature switch and the other that works when the AC is turned on.

If anyone plans to replace there mechanical fan with a efan or efans setup probably the easiest way to do it is measure the size of the raditor, hit a junk yard with tape measure in hand and find a vehicle with a simlar engine displacement and see if the efan setup will fit. Then buy one the commerical available temperature switch kits and install.

 

[aha2988]

You want to remove the fan shroud from the mechanical fan, it should help with low speed flow and if you need a larger fan it will give you a larger area to work with.

doesn't the fan shroud help flow? im under the impression that running without it would hurt the flow, isn't the the shroud supposed to dirrect airflow coming through the radiator across the engine instead of leting it flow around the engine? not arguing btw just currious on your thought

 

[450exc115]

Shroud is to help the fan pull air across the radiator. They call it a ducted fan as most fan losses happen at the tips, the closer you get the tip of the fan to the edge of the wall the less you lose and more air you pull through the fan. With out the fan it will act like block off plate where the shroud converges into where the fan use to be. I assume the electric fan you added had a built in shroud and that is all you need.

Does that help clear things up?

 

[aha2988]

Shroud is to help the fan pull air across the radiator. They call it a ducted fan as most fan losses happen at the tips, the closer you get the tip of the fan to the edge of the wall the less you lose and more air you pull through the fan. With out the fan it will act like block off plate where the shroud converges into where the fan use to be. I assume the electric fan you added had a built in shroud and that is all you need.

Does that help clear things up?

That clears things up thanks.

I wanted to update this thread with some new info that i've found through recent testing.

The Test: drive 30 miles to a buddies shop to hook up to his car hauler loaded with his jeep rig. Tow the jeep rig and hauler to Uhwarrie (20 miles from the shop) Leave engine running throughout entire test. Arrive at uhwarrie with rig, unload jeep, unhook trailor, go wheelin with fellow jeep wheeler. spend at least 3-4 hours on the trail at high speeds, med speeds, and crawling speeds. return to trailor reload jeep and tow home.

The results (cooling concern wise): with outside temp between 83 degrees and 90 degrees the hole day.... The 30 mile drive to my buddies shop engine temps stayed below the middle reading of the temp gauge.(pass) After hooking up and towing the jeep about 20 miles the engine temp peaked max at the middle needle position of the gauge.(pass) After unloading the jeep and unhooking the trailor as well as airing down my tires the truck had sat in the sun running for about 20 minutes idling. just before taking off into the trails the engine temp gauge remained at mid point on the gauge.(pass) Shortly after getting on the trail maybe 300-400 yards into the trail runing in third girl 4LO the temp gauge began to rise peaking at the 3/4 mark on the gauge. (fail) I had the A/C running as well which isnt a necessity offroading but its def. appriciated lol. I pulled onto the side of the trail an allowed the truck to cool in the shade before pressing on. After letting the Efan run without the engine for about 5-10 minutes the temps were back to normal. Restarted the vehicle and continued through the trail with the a/c off and all windows down. air temp on the trail was @ 87 with high humidity (it wasnt cold by any means). after about a mile into the trail came across a rather difficult pass of the trail (required low crawling speed higher rpm) My engine temps had remained normal durring the prior mile of trail ridding med-slow speeds low rpms.(50% pass w/o A/C) Durring the difficult pass of the trail running at crawling speeds higher rpms the engine temp began to rise again without the a/c on peaking close to the 3/4 gauge postion.(fall!) had to turn the heater blower on and open up the heater coils to flow a little extra coolant and utilize the extra fan the heater uses to blow air across the heatercoils.(fail!) nobody wants the heat on in the summer. got past the difficult portion and proceeded through the trail making our way back to the trailor to load up and head home for the day (shortly after getting back up to med-slow trail speed i was able to cut off the heat.) got the trailor loaded and headed out to stop by the store on the way out to air up my tires. (cooling levels staying at the mid mark) got to the store with the truck trailor and jeep, just as i pulled in the parking lot the engine temps started peaking again at the 3/4 mark pulled the vehicle into the shade and let it sit for a good 20 minutes while i enjoyed some beer and food from the store(fail) after cooling i towed the trailor back to the shop with no temp spikes back to normal cooling conditions (pass).

Over all results IMHO this fan is not moving enough air. FAIL I have an additional 8" diameter pusher fan i will be installing before the next trail run I will attempt to see if i can keep this mod cheap and refrain from splurging on a high priced dual fan until and or more expensive single fan.
With that said If your considering this modifcation please source a fan Im going to guess that pushes at minimum 3000cfm. However i will say This small fan has worked great for Daily driving and i have yet to see the temp at even the middle mark durring normal driving conditions. I have a documented one mile per gallon gain. I will continue to follow up on this modification as i add an addition fan. we will see how the 8" pusher works with the current setup first the next step is: instead of the 8" additional pusher, mount a second 16" identical as the first fan as a dual puller. I said this in a previous post i would not switch out the clutch fan for an efan unless the plastic fan blades have become broken and this provides a cheapr solution. that would be the only case i could justify removing the clutch fan it worked fine for cooling purposes before mine broke. However I am certainly satisfied with the benefits of the Efan i'll be more extactic when I get this setup to move the required amount of air. I'm sure i could remove the thermostate durring trail rides and this setup would be adiquit but thats not something i want to keep up with every time i go play off road. plus by the time i remembered oh you need to take your thermostate out it would have probably already been heated up and would require cooling before removing the thermostate.

 

[calinaki]

Hey aha, nice pics and nice Job. I'm doing the same thing to mine at the moment and am wondering what exact fuses you tapped into. Specifically for the A/C "on" control and for the ingnition signal. I believe it was the yellow wire for ignition and green for the A/C signal.

Thanks man!