seafarinman

I was thinking about my old electric fan that I was running, compared to the Taurus 3.8L V6 fan. My old fan ran so rough (vibration) that I could tell when the fan was actually working. The Taurus Fan on the other hand runs so smooth and quiet that I can't tell that it is on unless I have my window open. So I went to Radio Shack and picked up a small 12V indicator light so that I know when my fan is on. I have the part #272-335 Blue Snap In 12VDC Lamp Assembly (pair) that was $1.99 at Radio Shack. I simply wired one lead to the fan output and the other lead to ground. So whenever the fan is switched on at 185* or I switch on the A/C (A/C will override the 185* setting and switch the fan on anyway) the lamp comes on to indicate radiator cooling. I guess that my project when I get home to CA next week will be to install the high speed fan circuit with a DPDT switch (finally).

cruizin01

Ive thought about doing that too. Yeah I cant believe how quite that things runs, At first I was worried that it wouldn't push enough air just becuase of how quiet it is. I messed around with my thermostat controller on Friday and I think I got it to kick on and off right. But theres no way to tell unless u come to a complete stop and I can barely hear it then. So I think I might work on gettting one of those lamps set up, so I can make sure its staying off when Im goin down the free-way. That thing really kills my gas mileage when it stays on all the time :pat:. Thanks for the Tip!

Churnd

Why is that?

Rome - by "the fan's output" did you mean the ground wire going from the fan?

seafarinman

Sorry Chris.. I meant to say the 12V supply wire from the fan controller to the fan. So in my case it was the ORN wire from the fan controller harness. Basically connected in parallel with the 12V "+" wire on one end of the bulb, and grounded on the other end.

Churnd

Rome, I tried doing that with my fan a while back. I spliced into the wire going from the controller to the fan instead. It didn't do anything but provide a short to where the fan wouldn't come on.

seafarinman

Really? Well I am glad that mine works just fine. The light has really small wires on it, and I used 18ga wire to connect to the controller fan output (wired in parallel right where the fan wire attaches) and another 18ga wire that is grounded in the cab. Mine is a small enclosed bulb so it can't draw much power anyway. Like this but in blue since it is a "cooling" indicator:

http://www.radioshack.com/product.as...5Fid=272%2D337

BTW I like that pic of that truck on your wish list section of your site. (A bit outdated though!)

Robinhood150

Guys, does your electric fan (taurus or otherwise) stay on all the time? Mine does. I set the adjustable thermo according to the instructions, that is, the fan should turn on when the thermostat opens. At what temperature does the stock thermostat open?

I've been meaning to borrow a thermometer from work and monitor the actual coolant temperature.

seafarinman

Steve,
when I had the adjustable fan controllers mine would do that same thing. Once I swapped over to a fixed 180* fan controller and enabled it by wiring it to the IGN fuse, I have not had a problem. (Well the only problem that I had was sometimes the fan would not turn on. I think that it was related to there being a loose wire connection at the fuse holder on the fan controller. I have since cut it off and shorted the wires together since I have the factory circuit breakers that were attached to my fan in the car it came from~95 Mercury Sable)

Robinhood150

No, no, my variable fan controller works fine, it turns on when it gets hot and turns off a few minutes after the engine is turned off (well, it would if it wasn't wired to the ignition). But I was just wondering if your fan turns off when you're driving around. I've heard from other people that their electice fans turn off, but I think they had the 22re.

seafarinman

Sure my fan turns off when the temperature drops low enough. Since it has been pretty cool here lately, it really only turns on when I am at a stop light idling. Hence why I wanted to have a visual indication of exactly when it is enabled. My truck wasted 2 of the adjustable controllers before I had enough and just got a fixed temp controller. My controller comes on at 185* and my thermostat opens at 180* so it works great.

Robinhood150

Ok, I think I'm just going to have to play with my fan controller some more. So far it still works fine, I was thinking about adding an LED light to tell when the fan is on too.

cruizin01

-Chris, I would imagine that that fan pulls a considerable amount of amps when its on and doesn't need to be, compared with my old clutch fan when it worked correctly so Im sure it puts a drag on the motor. I mean its prolly only a few MPG but it is noticeable.

-Steve, your fan is doing what mine is...or was (I hope). Like Seafariman said it should turn off why your going down the road. If u want to try to adjust that Damn thermostat, Ill tell u what I did with mine. Go driving for a few minutes without a bunch of stops and what not then when u get back adjust the thermostat CCW untill the fans kicks off. Try driving around again and come back and c if the fan is on or off. If its still on try adjusting it till it shuts off again. This is what I did and I believe its working correctly. If its not Im gonna change my thermostat to 180 and buy a fixed controller. Hope this helps..Derek

bamachem

Ok, lesson on alternators...

They don't have clutches like AC compressors. That means they turn porportional the engine RPM's at all times - THIS IS NOT DEPENDENT ON THE ELECTRICAL LOAD AT THE TIME. The alternator produces more power than is consumed or your battery would run down. This is one of the reasons you have a voltage regulator on the electrical circuit between the alternator and the battery.

Therefore, by deduction, you can be assured that a 40 amp draw by a fan DOES NOT affect your gas mileage or engine performance (not from cooling, but from extra mechanical drag). Where you used to have a mechanical drive fan with a clutch, you have now removed that point of power loss and replaced it with one that is electric and adds no additional power loss - in other words, you should GAIN MPG's if the fan is running or not. the only way an electric fan will suck power and MPG's from your engine is if you have to upgrade the stock alternator with a larger one. Bigger Alertnator = Harder to Turn = Loss in Power when compared to stock.

Ok Class, any questions?

cruizin01

I guess youll have to excuse my ignorance then So by what your saying is there is no difference in what it takes to turn an alternator with nothing pulling on it versus having it moderatly loaded because the alternator is producing moderate or full amps all the time and are just being regulated by the demand needed with the regulator????Anyway I guess I learn something everday thanks for the techno info!!

bamachem

Don't worry about it! It's just that some people don't realize that increasing the load on the alternator does not affect MPG's but if you put too much of a load on it, then it will not charge the battery and it will eventually get drained and leave you stranded. You're not the first person to think that adding an electric fan will rob power and MPG's like the mechanical ones...

Robinhood150

Sorry I don't agree. It's thermodynamics. Yes there is a voltage regulator but there is no current regulator. Your alternator is not always pulling it's peak current ability. The formula for torque of an electric motor is:

T=K x Phi x I

where T=torque, K is a machine constant, Phi is magnetic flux, I is the current in the windings.

Also, power calculations for a generator:

P=T x w

where P=power in watts, T=torque in N-m, w is angular velocity.

Since P=IV

IV=T x w

T=IV/w, and V is constant and w is constant. If the current draw goes up, the torque also goes up. This torque is transfered to the engine via the pulley, increasing gas consumption.

Notice that both the motor and the power equations use I to find the torque, and not voltage. So the fan uses electricity which places more load on the alternator. This also explains why, when I turn on the taurus fan to hi, my engine RPMs dip for a second. This also explains why a regular generator will also slow down momentarily when a electrical appliance is used.

For further evidence here is an article about how using day time running lights will use more gas. http://auto.howstuffworks.com/question424.htm

You wouldn't need a bigger alternator to run DRLs, yet they do use more gas.

AkitaDog

iTrader: (1)

I just recently installed the Taurus fan on my rig, Thanks to you guys on this forum.

I also wired the high speed circuit also.

I just wanted to share my idea and setup I did on mine.

I took the 4Runner rear heater switch which has a LOW & HIGH postion plus an off position in the middle which is a nice feature for those of you that want to shut the fan off for water crossings.

cruizin01

Steve thats why I didn't understand fully what bamachem was trying to explain. Like you were saying with the Rpm drop when the fan kicks on or when I crank my stereo up. I didn't understand why the engine would slow if there was no extra load on the motor from the alternator??? All these darn systems

Robinhood150

So what do you use for the rear heater switch ?

AkitaDog

iTrader: (1)

I don't have the rear heater anymore, didn't use it, didn't need it.
So I replaced the whole heater console with a non heater console.

That does not mean you have to remove your heater unit, you can go a wrecking yard and get the switch from one of these units.