Thread: Electric VS Mechanical cooloing fans

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I'd like to ask for opinions on Electric VS Mechanical cooling fans.
For many years most auto makers build their cars with a belt driven from the crank shaft. The system works/ed for many years with very few moving parts and little needed maintance.

Now it seems like all the new cars/truck have electric fans on them. Again the system works but looks like alot more parts to have problems with.
Are electric fans the best way to go? Is the added stress to the charging system out weigh the lose of HP from the mechanical fan?

I have a mechanical/belt driven fan on my truck now but the dern thing sounds like a C130 driving down the road from all the fan noise .
My truck is used mostly for towing and local driving.

There's no need to change it out if it works. I think many of us have gone to electric fans because they cool large engines better and free up a few horsepower.

Originally Posted by rumrumm

There's no need to change it out if it works. I think many of us have gone to electric fans because they cool large engines better and free up a few horsepower.

And they fit in small spaces where a mechanical clutch/fan unit won't.

I use an electric fan on my Bucket with a on/off switch on the instrument panel as out on the open road the engine runs at 180 degrees and I only have it on in slow traffic or around town cruizing.

I have an electric fan only because I didn't think I would have enough room for a conventional/mechanical. It ends up that I have more then enough room with the amount of engine setback even with a 'long' water pump. One reason for an electric fan in an open hood car like mine or a 'bucket is safety. If I get dinged by my electric, it will a dammit, that hurt vs a trip to the e-room with your finger on ice, hoping it can be reattached

I had this discussion with the guy at Griffin radiator. He correctly told me that a mechanical fan will draw more air than an electric fan and will cool better with a properly designed fan shroud.

Car makers switched to electric fans because the electric fan could be switched on/off at will so the drag on the engine was controlled. Such allowed more precise engine temperature control and faster warm up. A thermostatic mechanical fan kinda does this but not as well. Also, like rspears said, there is a considerable space savings.

I have switched three Chev 350 engines from V-belt to serpentine using EBAY brackets from a 96-99 Vortec motor....the sound reduction is amazing.....if you remember to use both a reverse rotation water pump and a reverse fan blade.

Electric fans ratings are bogus because they rate the CFM at some unrealistic pressure....
I have yet to see an electric fan that looks like quality....they all look cheezy and cheap...like they came from Harbor Fan or something.

mike in tucson

Things I've learned from this thread so far.

#1. Mechanical fans more more air....This is a good thing since I'm towing.
#2. Electric fans work best in tight areas...... This is not a problem for me. I have plently of room.

For either, a really good fan shroud is important....one with no gaps that leak. Remember, you are trying to get the air moving across ALL the radiator surface....not just the small circle that the fan projects onto the radiator.

I could pretty much sign my name to Mike's post and be done with it.
One other thing though, is the thermostatically-controlled fan clutch. Sounds like you don't have one, so the fan is running water pump speed all the time. Mounting a clutch will reduce noise and improve fuel mileage.

As far as whether you can save any energy with an electric ANYTHING, if you have studied any physics at all, you will learn that it takes the same amount of energy to move "X" CFM of air, no matter whether you are doing it mechanically or electrically. The electric fan just puts more drag on the alternator, which is crank-driven!!!!

You can rate electric fans by the amps they pull---the fan from the earlier Viper is a very good choice for a single fan

Also the best out there are the fans used on the Tauras and Lincoln s
Check out GT_Recycler on E Bay for reconditioned ones--I have bought several from him, they are recond and packed very nice at far less than $100

Many of the V8 converted Astro vans use the Crown Vic 14" fan that is two speeds and you have to use the two relays also.Last time I looked at that,in summary,I remember they do one heck of alot of air.Tons more than the mechanical fans.As stated a well designed and applied shroud is key.

Fan shroud.......... Yes. Its the OEM that I am using and it seals the rad very well.

techinspector1

could pretty much sign my name to Mike's post and be done with it.
One other thing though, is the thermostatically-controlled fan clutch. Sounds like you don't have one, so the fan is running water pump speed all the time. Mounting a clutch will reduce noise and improve fuel mileage.

No Sir I dont have one.......I thought it was better to reduce rotating weight but if I can get lower noise and better fuel mileage I'll be getting one asap.

An electric fan is what you use when the stock one isn't cuttin it. I have three on my sbc s. They all run kooler.i don't care what they tell you they won't let you down like a stock fan, that speeds up-----then down .up then down . Having the same amount of air at all times fixes heating woes.My stock LT-1 motor came with one so it has one as well, never been a problem. When building a hot rod whatever!! . these components should be thought out carefully.. as over heating in a street rod, is not an uncommon occurence, just because someone picks up a fan and sez "there this oughta do it" doesn't mean it will do the job..I've seen this more times than i can count. If the new car manufacturers use them on their cars [most all] they have to be right ..right JMO

As is in my case sinse I didnot move the small block back, face of pulley to rad is 1/4 inch, ( Lower left of pic )so I have a 16 inch spal pusher in the front, it will not come on til I get into traffic, comes on at 185 and usually stays in and around 200...

I run electric fans for a couple of reasons besides the fact I think they work better. One of the reasons is that I don't run hoods and don't want a spinning weedwacker when I am fooling around with timing, or other chores. The other reason is that I have seen the results of a fan blade exploding. A guy I know with a 50 Ford was driving along and there was a terrible explosion under the hood. One of the fan blades sheered off and imbedded itself into the hood. I saw the gash it put in there and can only imagine what one would do if it had no hood to contain it.

Don