Question about electric fan

[Dark]

I just bought a 14" electric fan that flows at 1350 cfm

Is that enough flow for me to get rid of the clutch fan? My car is stock and it will most probablly stay that way

[Bill Roberts]

Yes, that will work for all but the hottest days running wide open for hours.

I see no problem at all with it...but a pair of smaller fans is actually better. The key is to run air through the entire surface of the radiator (hardly possible...but remember, the right side (from the drivers seat) is hottest.

I ran mine with the factory fan alone (running all the time) and did not have a problem. If you live where it is 110 degrees (like the desert) then NO fan is big enough.

Our cars are comfortable to about 104 outside temp...after that...it is hell on readiators. I was in 108 temperatures and my clutch fan stayed on all the time dragging the engine down (but is certainly sounded cool)

[twitchy]

bill, is it hard to remove the old fan and rewire the electric one to come on all the time and do you notice a difference at all in performance, mileage, sound, etc?

[Bill Roberts]

You pick up a few horespower without the fan...especially when the fan clutch "was" engaged.


The eletric fan will suck at the alternator as well. I think it is more about spool-up power than overall horsepower. A shade more responsive (very little IMHO)

I wnt back to my clutch fan due to having an alternator that is weak for now.

I would wire it on a switch. Any 12 volt hokup and a switch to the cockpit so I caould turn mine on at will...or just wire to a hot when ignition is on.

Do not run the car with no fan bringing air over the radiator...sure way to overheat.

[Dark]

I just found another 14" fan that flows 2950 cfm if I wanted can I set up one fan as a puller and the other as a pusher where one operates at 170 degrees and the other at 200 degrees?

[zero.counter]

It sounds almost like you are applying the ATX computer cooling solution to the engine bay area or attempting so at least. :D
Are you talking about a dual fan setup with one away and one toward in a cycle motion? If so, then the temp cut on switch would be feasable but you might want to make sure that nothing impedes or restricts the airways going out (to blow the hot air) also now that i think about it, wouldn't it be better to build some sort of air exit from the engine bay (those fender vents) and just use one large high capacity fan blowing in?

[radhaz]

I think the fender vents you are referring to might be the Z3 universal fender vents. If you were really concerned about heating issues then yeah if you make those "functional" they could help, so could louvre'ing your hood which would look less ricey in the end.

[zero.counter]

Originally posted by radhaz
I think the fender vents you are referring to might be the Z3 universal fender vents. If you were really concerned about heating issues then yeah if you make those "functional" they could help, so could louvre'ing your hood which would look less ricey in the end.
Actually, what I meant to say was wheel well vents, they sell for about $60 the pair, and are universal, you cut into the wheel well mold and fit. Then he could fabricate some funnels for engine compartment air removal. They are used for venting from the cowl or bumper area, but could be used up higher in the well from the engine bay with, again, some fabrication and cutting if need be.
Here is a link (http://www.importfan.com/product.asp?3=4550)

Those cheezy Z Fenders are not what I was speaking of, they have little or no use in this discussion.

[YellwMonky]

wow...i've never seen those before. This summer has been giving me a little overheating problem ( i have one 14 in elec. fan). how well do those work?

[twitchy]

how does the clutch fan know when to engage?? LIke a temp sensor or something tells the clutch when to engage??

anyone think Id benefit at all from getting an aluminum fan blade to install in its place? (aside from the looks?)

[Bill Roberts]

This is how a clutch fan knows when to engage..

If you look at a round thermometer, as it gets hotter, the needle swings clockwise. Their is a wound spring (just like a thermometer) and when it expands, it winds and this is what engages the clutch on the fan and locks it to the water pump shaft. When the fan cools things down, the spring contracts and the clutch disengages and the fan goes to slip mode.

[Dark]

Originally posted by zero.counter
It sounds almost like you are applying the ATX computer cooling solution to the engine bay area or attempting so at least. :D

zero.counter

I'm asking these questions because I keep having overheating problems. I really like pushing my car to the limit. The clutch fan just can't keep up. My stock electric fan is dead so stop and go traffic right now is very nerve racking. What i want to do is put one 14" inch fan behind the radiator and a 10" fan infront of the the radiator towards the passenger side. The 14" fan would be wired to operate at 170 degrees and the 10" at 200 degrees. The reason i like this idea is because i can add the 10" fan later and if the 14" fan ever fails i at least have a backup. So my car can at least stay functional which is why i'm asking if it can be done. Keep in mind that I don't have a lot of money to work with and you will see why this makes sense to me.

[240 2NR]

Before dropping cash on lots of fans and time on elaborate wiring systems, make sure other issues are sorted (bill posted a great list in tech) before blaming the fan for not pulling enough air. Secondly, airflow above 30mph will never be matched by a fan and would be a worthless draw on the system (if I recall correctly other than temp the clutch fan disengages at 30mph and 3rd gear or higher).

If you're still overheating with electric fans check to make sure you have enough shrouding so it's pulling through the core and not around it.

[240 2NR]

Originally posted by Dark
zero.counter

I'm asking these questions because I keep having overheating problems. I really like pushing my car to the limit. The clutch fan just can't keep up. My stock electric fan is dead so stop and go traffic right now is very nerve racking. What i want to do is put one 14" inch fan behind the radiator and a 10" fan infront of the the radiator towards the passenger side. The 14" fan would be wired to operate at 170 degrees and the 10" at 200 degrees. The reason i like this idea is because i can add the 10" fan later and if the 14" fan ever fails i at least have a backup. So my car can at least stay functional which is why i'm asking if it can be done. Keep in mind that I don't have a lot of money to work with and you will see why this makes sense to me.

For what those two fans are going to cost you could almost just buy a bigger core (you'd be half way there at least with any decent fans) and not have to worry.

Again, check the cheap stuff like the condition of the coolant, water pump, thermostat, cap, etc before replacing the fans ath twill only mask a problem that still exists.

[Dark]

I'm doing this primarily for stop and go traffic cause that's the only time the car overheats. Which is why I need the electric fan right now the clutch fan is the only thing that's helping cool the car. Which in the summer is not enough. If the electric fan keeps the car cool even in the worst kind of traffic then I plan on getting rid of the clutch fan.

I just replaced my water pump, thermostat, coolant and cap the cooling system is fine I used the burb hole a couple of times and most if not all of the air in the system is out. I plan on doing a write up once the parts arrive with lots of pictures.

Everyone thank you for your support and constructive comments.

[radhaz]

This is slightly O/T but when I saw them it reminded me of my first reply to this thread.

JDM Vented Fenders for the Nissan S14, S13 and RPS13 (http://www.speedalliance.com/kits/silvia_vent_fenders.html)

[Bill Roberts]

I love those fenders...wish I had some and I KNOW they work well too. I saw them and massive amounts of hot air was coming out of the vents.

That is one body mod that not only looks great but is very functional.

When I am at the local drive-up, at idle, I gun my engine and the clutch fan engages, I feel the heat now rush by my arm sticking out of the window. I would really love to have a pair of those.

[old_s13]

There is a bit too much confusion in this thread:

1) The OEM clutch fan is temperature controller, not speed controlled. There is oil inside the clutch and a temperature controlled coil which as the temps increase, it clamps harder on the fan. Basically, when the clutch is cold the fan spins less -- conversely, when its hot.. the fan almost matches the rpms of the car. If your fan clutch ever fails or your car really overheats, you'll see how loud the OEM fan setup can be!

2) Electric fan setups are ONLY advantageous when used correctly. The key with e-fans is efficiency. Like any fan, e-fans need a shroud and must sit ON the radiator, nice and flush. If the fans are not seated correctly, they will not be as efficient. Also, e-fans should not be on all the time. They should be controller with a thermostat. I set mine up to activate at 200°F. Once the car is cooled, they turn off.

3) I cant imagine push AND pull fan setup being advantageous. If you're going to spend your time and money, DO IT RIGHT. Make sure your coolant system is fully operable before you start throwing money around. This means you have nice and new coolant, thermostat, water pump and radiator are all functional. Once you have that out of the way, you can go with e-fans. Besides, ALL FANS are basically useless once the car is in motion! Fans are only good for low-speeds and traffic.

4) Depending on your climate and motor setup, you may want to increase your radiator size. With my KA, the OEM radiator was fine.. I got some fans from the scrapyards.. probably off of a volvo or altima, I cant remember. I mounted them and wired them up to a thermostat -- worked great. However, now that I am going with my RB motor.. I decided to step-up the radiator size/quality. I went with a larger fan/radiator setup:

http://www.clearcorners.com/fans1.jpg

Good luck everyone,
- Mike