Electric Fan is it a better fan???

Hello first of all I wanted to know if it is adventageous to replace the water pump fan for and electric fan. Also The electric fans require hooking to a 12v positive ignition source so it starts working when the ignition is on what is the best 12v positive source on the maverick the positive side of alternator.

 

the only advantage that i know of is that it frees up the horsepower taken away from your mechanical fan setup

 

It doesn't take away any HP. The horse power that used to drive the fan now has to drive the alternator (plus a little) to power the fan. Why does it take more HP? There are losses in the alternator drive system, the alternator electrical system and the motor of the fan.
There is no free power - the engine makes the power for everything in your car.

 

That was my guess. I assumed since it is electrical the motor wasnt turning the alt any harder than it ever has. But I dont know anything about electric fans anyways.

 

Before I did my electric fan setup, I just popped the belt off and drove it around the block...it really is a pretty noticeable difference (that was mostly stock motor).

Run the fan off a relay, preferably one that is tripped on and off by the temperature of the water.

Pics and description at my website...http://scooper77515.fordmaverick.net/august2005.htm

Relay wiring...



And temp relay...



Some may not like the extra wires all over the place.

 

PaulS, I always pay attn. to your posts because you really seem to know your stuff. I'm confused some by this answer though. I guess my lack of alternator knowledge is the culprit. Are you saying the alternator is actually harder to spin under load? That is as electrical needs rise the alternator is harder to turn increasing resitance on the motor? That's the only way I see going to an electric fan not freeing up some power, afterall, the fan is spinning grabbing air and pulling it through the radiator that is a drag on the engine that you don't have with an electric fan. Or is there not enough drag to turn the fan as to be noticable?

 

That's true.

The advantage in the electric fan rig, when correctly done, is not that it takes less horsepower to turn the fan than a clutch or flex fan - that depends on several factors. It's that you can use a thermostatic switch to run the fan only when it's needed. Certain clutch fan mechanisms can do similar, but the electrical is more tunable and efficient in that regard. An electrical fan causes no additional load when it's off, unlike a flex fan. Plus you can turn that fan on at full power regardless of engine RPM, or even with the engine off.

 

One thing that was not mentioned here is that as rpms increase, so does the drag on the motor when using a mechanical fan, especially fans with solid blades. That is why you see flex fans. The 302 in my Comet came with a flex fan from the factory. As rpms increase, the blade flatten out and that high rpm drag is lessened, but it is still a factor.

An electric fan usually only has one or two speeds. It may increase the load on the alternator a bit, but it is probably only equivalent to a mechanical fan at idle or a little above, and it remains the same at all engine speeds. For racing purposes, electric fans are great. It would be hard to measure a gas mileage difference, but it can't possibly hurt there too. I will probably change mine over.

At highway speeds, you almost don't need a fan at all because a lot of air comes in through the grille on older cars like ours, so by the time a mechanical fan hits those higher rpms and maximum drag, it is almost not necessary anyway. Overall, electric fans are just a better idea.

 

I have an electric on my car and the difference is noticeable. It has been proven on a dyno that electric fans use less horsepower. Don't remember the link to the article, but it was a test some magazine did (they found that some mechanical fans use up to 20HP!) Plus, the fan shuts off when ever it is not needed, whereas a mechanical fan just runs all the time. Electric is the way to go.

 

Electric

I would make certain that you have a indicator light that runs when the fan is on - this will help you prevent your engine from overheating if a switch or relay fails and the fan doesn't turn on. I had an electric fan and water pump that I turned on with the same switch, and when the switch failed - no water pump either...

 

since the fan is not needed at highway speeds, would it be of any use to turn it off at <45mph by use of speed sensor/manual switch (make sure you turn it back on!!) or am i wanting to over complicate the system for little/ no results.

i would look at my Malibu to figure out if it shuts off at speed, but i am driving it at that time an can't here the fans over the radio (or the lifter click it has).

 

You just need to get a controller that turns it on and off automatically based on the engine temp. They can be had at most auto parts stores. I have mine on just a manual switch with a relay, even with how hot it is outside, I still hardly ever turn it on unless I get stuck in traffic or something. As long as I'm going above about 25 - 30 mph, the car stays cool without the fan. The temp creeps up maybe 15 degrees when I have to stop at a red light, but rarely do I get caught by a light that lasts long enough to warrant turning the fan on. Probably 90% of the time I leave the fan off, just got to keep an eye on the temp gauge periodically.

 

i use a controler that is common at most auto parts stores. it useds a borbonic(sp?) tube that zip ties to the radiator. then it has a adjustable knob that lets you adjust when the fan turns on and off. Its only around 25 to 35 bucks. I put the tube sensor thing on the out let side of the radiator. that way it is sensing the temp after the rad has cooled. this way it turns on the fan when there is no air flow on the radiator and when your going fast enough it turns it off. It works really well.

 

I want one just because Frank has one!!

 

Mine is plumbed into the top of the intake manifold. Works like a charm. And wasn't too expensive (HELLO... Mr. CHEAP here...)

I had a serious problem with overheating for years, until I went with the aluminum radiator and the setup I have now. Even on the hottest of days, no over heating issues anymore.

I can watch the temp gauge and when/if it hits 190, usually at idle in the garage, the fan kicks on and within a minute or two, it is down to 175 and turning itself back off. Stays off for about 4-5 minutes before it warms back up to 190.

It seldom comes on when I am driving due to the air being forced into the radiator.