Maxwelhse

I do... With that setup you have the option to forget to turn it on or off.

At least get one of the cheap automatic fan switches ($20). You can always wire up a manual switch as an over ride if you want.

GTstangB.F.D.M.

no a/c.. also, i was told the two black ground wires determine wether it pushes or pulls..

Maxwelhse

Whether or not that is true (I never tried it since I always wanted mine to PULL), you NEVER want a fan to "push" against an obstruction (radiator) if you can at all help it.

The logic behind it? Air is compressible... When you "push" air with a fan you have about 15% efficiency loss due to that compression.

I know, once again I'm not answering the question that was asked, but pushed fans are bad mo-jo as far as cooling systems are concerned and are only, at best, a band-aid on a real cooling solution.

GTstangB.F.D.M.

well said. i plan to leave it 'pulling'.. BUT i was thinking, man if you really had cooling issues and need all you could get.. a small 12incher on the front 'pushing' paired with the puller on the back side.. that would really move some air! lol

however, it also seems kind of redundant. lol

Maxwelhse

The only time I've seen a small pusher make sense is for A/C performance (or just flat out out of space to put something on the rear),

Generally a little fan out front of a big fan just acts as an air obstruction to the big fan behind it.

GTstangB.F.D.M.

makes sense.

GTstangB.F.D.M.

ok... again.. I'm lost.. trying to order the crap to wire this fan up.. including relay, wire, fuse, etc..

looking for help on the wiring aspect... PLEASE!

when wiring this, do i run lets say, 10 ga from battery to relay? and 10 ga from relay to ground? and then from relay to fan and switch can be normal 18 ga wire?

can't find any real info or help on this.. please let there be an electrically inclined God out there.

Maxwelhse

The relay coil wiring is light duty (both power and ground) and the load wiring itself should be of sufficient gauge to run the appliance the relay is powering.

The ground from the fan itself should not be run to the relay at all.

Without trying to sound like a jerk, do you understand the basic principal of how a relay works and what you're actually using it for?

If you're not totally sure, go here and read: http://www.the12volt.com/relays/relays.asp

Pay careful attention to the part of the diode. Many high quality relays already include the diode, but many do not. Since your fan will be spinning under the force of wind, even when the power is off, it can induce a current that can spike the coil. As far as how big of a diode for X application and all that, you're gonna have to do some googling to get your answer.