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EZ-Wire : Fan Connection

4K views 11 replies 4 participants last post by  horvath 
#1 ·
Duh ... please help!

I'm getting ready to do my EZ-Wire kit ... just went through *all* the wires, rerouted some to different sections, etc. ... and today, I was out lookin' around at the truck, and I'll be hanged if I know where the fan is!!!

Isn't it supposed to be in front of the radiator? My AC condenser is in front of the radiator ... but no fan! Where is my fan, man??? LOL! HELP!!!
:(

Alan Horvath
<a href="http://AlanHorvath.com/" target="_blank">http://AlanHorvath.com/</a>
Acoustic Rock ... for real.
 
#2 ·
You probably have a stock radiator fan on your water pump so you don't need an electric fan and that circuit is surplus. If you can fit in a stock fan it is ALWAYS superior to an electric. Electrics became popular when we started stuffing BBCs and hemis in in roadsters and coupes that were designed for 4-bangers. Trust me, if I could fit a stock type fan in my Willys, I would do it in a NY minute.

Just use that surplus fan wire for your flashing neon under-fender lighting!
 
#5 ·
Okay ... I get it.

Mechanical fan is the one that I think is on ALL vehicles.
:D
The one that has the fan belts, turns the alternator, etc., etc. ... and the EZ-Wire kit is just giving me an optional deal for an "extra" cooling fan -- right? Thanks, Willys36.

Okay ... cool. I was thinking about putting an electric fan in and having a switch for it on my dash ... like you said EBlack36 - heavy traffic, temp gets high, throw the swith to the electric fan and I've got extra cooling power.

What's buggin' me now is, with the AC condenser in front of the radiator, where would I put the cooling fan??? And isn't that a poor location for a condenser (sitting there in front of the radiator - blocking incoming air)?

Thanks guys.

Alan

[ March 26, 2003: Message edited by: horvath ]</p>
 
#7 ·
Without going into a big discussion of thermodynamic cycles, suffice it to say that an air conditioner condenser coil MUST be in as cool an air flow as possible. System efficiency drops off very rapidly and compressor pressure (stress and wear) goes up fast too as the air temperature rises. The engine cooling system is less sensitive to air temperature so the standard practice is to sacrifice the engine radiator in favor of the condenser.

I plan to adapt a small, square condenser with integral fan that I got at the junk yard off a foreign car onto my pickup. Since the cab volume is small, that should be enough condenser to service it. Instead of putting it in from of the radiator, I will try to cut a square hole in the fairly large sheet metal pan that sits below the radiator and spans the area between the grille and radiator. It looks like I can mount the condenser there, flush with the pan and with the fan underneath sucking cool air that enters the grille. Still a few weeks from getting to that step but will keep you posted.

The problem of running an electric fan and a mechanical fan at the same time is that to perform at their optimim, both should cover as much of the radiator core as possible and be close to the core so the air doesn't leak out the edges but goes thru the core. Thus since the mechanical fan sits behind the radiator by definition, the only place for the electric fan is in front of the radiator. The electric fan actually serves as a fairly effective restriction to air flow when it isn't running so is a self fulfilling prophesy - it causes itself to come on sooner than it might have - the only reason it is necessary is because it is there!! For a car that ins't in search of every last horsepower which is what your truck sounds like, the power loss from the mechanical fan is miniscule. In fact, that is a deceptive arguement since you must move air. It takes a certain amount of power to move a certain amount of air, regardless of whether it is an electric fan or a mechanical one. Sooner or later your engine will need to put the same amount of energy into moving the air. If you run an electric fan, the alternator will draw the same power(or even more because the energy transfer is less efficient than the mechanical fan) from the engine for use by the fan motor. Thus, there really isn't an overall power savings. The advantage come is at the drags where you can shut off your electric fan for 1/4 mile and save the power that the mechanical fan uses continuously. However nothing is free and your generator will draw the power to run your fan on the drive home. There is a slight advantage to using an electric fan since it can be placed on a thermostat control and run only when needed. They did this with mechanical fans by adding a thermal clutch mechanism which only spins the fan when the air temp increases. You can even get an after market fan clutch if that is a concern to you and that takes away any advantage the electric fan might have had.

My personal preference for a street car in order are

1. mechanical fan with shroud
2. bare mechanical fan
3. puller electric fan with shroud
4. bare puller electric fan
5. pusher electric fan
 
#8 ·
I run both as I my engine sits very low in the engine bay as compared to the radiator and the mechanical fan is in the bottom half of the radiator. I am using a puller electric fan on the top half of the radiator and it seems to work very well, on the highway I run about 165 to 170 with just the mechanical fan on. When I get into traffic I turn on the electric and never get over 190 to 195. may not work for everyone. but it works for me. If my Mechanical fan was centered in relation to the radiator I would only use a Mechanical Fan. :cool:
 
#9 ·
Originally posted by EBlack36:
<strong>I run both as I my engine sits very low in the engine bay as compared to the radiator and the mechanical fan is in the bottom half of the radiator. I am using a puller electric fan on the top half of the radiator and it seems to work very well, on the highway I run about 165 to 170 with just the mechanical fan on. When I get into traffic I turn on the electric and never get over 190 to 195. may not work for everyone. but it works for me. If my Mechanical fan was centered in relation to the radiator I would only use a Mechanical Fan. :cool: </strong><hr></blockquote>

Good application of an electric fan!! Fulfills two of my rules - cover as much core as possible and pull whenever possible. :D
 
#10 ·
Hmmm ... I've learned some new stuff today!
:cool:
Thanks, Willys36!

My fan covers the radiator quite well, but I don't have a shroud! I was surprised the past couple of days when it was hotter outside and my temp didn't rise at all ... so it's looking like I probably won't need additional cooling after all.

Will the addition of a shroud make a big difference? I'm gonna put one on anyway because, why not - eh?

Alan
 
#11 ·
I run my PU wiht stock 235 4-blade fan and stock TIRED radiator and rarely does temp climb over thermostat setting, even in Bakersfield 110F summer days. If yours runs like that, you don't need a shroud. If after adding tranny cooler and air conditioner it begins to get hotter, shoud might be needed.
 
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