Sorry to bother with such a basic question but I don't know wiring too well and want to remove my mech fan in favor of a efan.

The problem is i'm relocating my battery to the bed at the same time so I was thinking of runnig the power lead to the fan from the distribution block on the firewall rather then running a cable back to the battery.. here's a diagram I drew up of the battery relocation, location of everything for reference
http://img154.imageshack.us/my.php?...erywirinxb4.jpg


Now I've been told that I don't have to do that and just tap into a "Switched-on" power lead which I can do but is that all I have to do to supply power to the efan? and if I do this where should the 40amp relay and 40amp inline fuse be wired in at?

I mean the fan itself has only two wires of course power and ground and the relay has three(two red and one black) so the ground from the fan will get grounded.. then the power wire from the fan will go where? to the switched-on power lead or to the relay? im confused sorry and thanks for taking the time to read/reply to this in advance

Ryan

I think I may just have this figured out..

Fan has two wires (black/red) Run the black to ground, run the red to the relay(has 2 red and 1 black wire).

Run the un-used red wire from relay to power source which in this case would be the green ic pump wire which is a ign power source.. im thinking between this and the relay is where the inline fuse should go yes??

Run the black wire from the relay to ground

Does this all sound correct?? come on I know someone in here had to convert there rod from mechanical fan setup to electric

go to http://alanhorvath.com/54chevy/mad_electrical_2.php Then read through that and see if thats not the kind of set up you might need. I know allot of folks don't like fuseable links but I tried to wire my fan with a fuse and it just kept blowing out, to much of a sudden draw I guess. I know that this set up that Alan has worked for me on my truck.

Doc here,

The Proper way to wire the relay is:

• RELAY COIL POWER #85 = 18 Gauge Red , to Switched , Fused (1 Amp ) , 12 volt source.
  
  
• RELAY COIL GROUND #86 = 18 gauge black, to temperature sensor device OR hard ground OR both, depending on status, (Auto/manual)
  
  
• NORMALLY OPEN CONTACT #87 = (if battery is in trunk) 8 gauge wire to the current source Via a proper FUSE LINK.
  
  
• MOVABLE CONTACT #30 = 10 gauge wire to the fan Power wire.
  
  
• NORMALLY CLOSED CONTACT #87A = Not used for this application.

DO NOT attempt to use a standard fuse for the fan circuit side of the relay, (only the coil side), A fuse , say 40 amp compared to a 40 amp Fuse link will open on "spikes" as opposed to a link which takes time and heat to open, A fuse will open if it sees any current above the pre determined value within milliseconds, and you will be constantly blowing that fuse and overheating your car. A link takes seconds to minutes to open the joint.

Doc

__________________
Aftermarket Solutions
Electronic & Electrical
Innovations

All of the above is great info on how to get this done. However, it appears from your diagram this setup will run the fan constantly. My question is: is that your intention or do you have in mind some other method to control when the fan runs? I would not think you would want to run the fan whenever the ignition circuit is powered. An alternative perhaps is the DeRale thermostatically controlled fan relay kit. Simple to install, the on/off temp can be set, kit contains the relay and instructions, and it provides a manual / AC override as well. Has worked well in my T. My .02. Good luck to you.

Source: http://store.summitracing.com/partd...15&autoview=sku

hello you might want to think about a thermostatic temp switch in block and then run relay ground to it. that way when engine temp gets up to switch close temp fan will come on. it wont run all the time. you can buy temp switches at all temp settings. you also wont have to wire a switch in to turn fan on and off.

Guys,

Thanks alot to all that have replied.. great info in this thread and I really appreciate it.. From reading this and from what another syty owner has told me that has wired up a very similar electronic fan here's what I've come up with.. tell me what you all think and what gauge wire to use for each.

http://img.photobucket.com/albums/v...efanwiring2.gif

Also the question about how I want to control the fan.. I plan on using a toggle switch for now just so if I need it off I can turn it off but it'll mostly be on. Later I plan to tap into the lower intercooler pump which the turn on/off can be controlled via the ecm but that's going to wait for a while.

Doc here,

Use 10 Gauge wire to the battery source And to the fan motor..

The Relay coil and grounds can be 18 gauge..

Use a 50 amp fuse link for the fan source current, a standard fuse will never hold up, and you won't know it until your engine is already overheated.

Doc

__________________
Aftermarket Solutions
Electronic & Electrical
Innovations

Doc,

From what i've seen of this fan it only pulls about 30 amps but does have a spike during initial turnon to about 35amps so my 40amp inline fuse should be good right? Also so i'll be using 10 gauge wire off the 30 pole (to distribution block) and off the 87 pole (to fan positive) but what about pole 86 (12v switched on power) im thinking this will need 10 gauge as well correct?

again thanks alot for the help and the spoon feeding you guys have done for me on this subject so far

85 and 86 are the relay coil and grounds (low current relay circuit). Just a small amount of current is needed to supply the difference in potential which will activate the relay's high current switch. As Doc suggests, 18 gauge wire should be enough.

As an aside, I run both a fuse link and a fuse on the 10 gauge wire that comes off the main terminal block to the input side of the relay. I found that I was occasionally blowing a 30 amp fuse on this line (about once per month). I installed a 40 amp fuse and have had no problems this year in the last 2400 miles. The fuse link itself has been trouble free as one would expect. I run a single 16", 2600 cfm fan on a thermostatic relay. If you are concerned about running a lot of current through a single relay (such as running two fans or a very large single fan), using two relays in parallel might a be a good idea. I have been waiting for my single relay setup to exhibit problems, but so far no failures. If it does, I already have the twin relay setup in my tool box ready to install. By the way, I carry spare relays and fuses with me so I can temporarily deal with a problem on the road.

Thanks for the input sir, and yes that's a good idea to carry spare fuses/relay with so i'll be doign that as well.

the fan im using has been installed in my app before with great sucess.. it's a single fan that puts out 3000cfm with spiking just under 35 amps during initial turn on so far on our applications. Oh the fan is out of 2001 s80, v70, s60 Volvos and can be found for cheap and are really slim.

Doc here,

A fuse link is designed to hold Current until a predetermined amount of time has passed before opening..(Spike Curve)...A FUSE won't ...

This includes incidentals where head winds may be quite high, or road fodder (like sucking in a plastic bag..) poses a quasi rotor lock on the fan motor..at which time the current can rise quite high...

Always use a Fuse link..

Doc

__________________
Aftermarket Solutions
Electronic & Electrical
Innovations

Doc,

Im not sure how or where to wiring up a fuse link.. I would like to since you make a vaild point but lack the knowledge to do so.. so if you wouldn't mind spoon feeding me some more info in idiot terms i'd much appreciate it.

Doc here,

Install your fuse link at the terminal post, where the power to the RELAY CONTACT for the fan picks up the power to the contacts..(Where your original fuse was located in your DWG..)

This would be the 10 gauge wire going to the # 87 terminal of the relay, the # 30 terminal is the 10 gauge wire going to the fan motor.. The #87a terminal will not be used..

By running the power to the #87 terminal, (instead of the 30 terminal or movable contact) It leaves the 87a terminal "cold" to power when the system is in any configuration..so you can't short it accidentally with a tool or a watch band while working around it.

Doc

__________________
Aftermarket Solutions
Electronic & Electrical
Innovations