mt_goat

Here's the test fit of the Taurus 2 speed fan:


The shroud I made came was hitting the steering gear box, so I had to do a little grinding on the shroud to get some clearance:


Here's the backside of the shroud:


The controller is a Delta Current Control (DCC) FK35:
http://www.dccontrol.com/0820.htm
The nice thing about this controller is it is variable speed, rather than cycling on & off it will only spin the fan fast enough to keep below the temp setting. That gives it a soft start and less overall power drain on the alternator as well as keeping the engine at a more constant temp equilibrium.

I wired the DCC controller to the high speed wire of the Taurus fan motor since it will automaticlly slow the speed down when needed.

The slow speed wire of the fan motor I hooked up to a competely seperate power system so it can be used as a back-up if the DCC system fails.

With this "on-off-on" switch:

I can go from the DCC controller to the backup with the flip of a switch. The "off" setting can be used for deep water crossings to keep water from damaging the fan or throwing water up into the intake.

Edit:Just found out from Brian @ DCC the proper way to bypass the DCC controller for deep water crossings is to switch the small yellow controller input wire from 12 volt "+" to "ground". http://www.dccontrol.com/circuits.htm

I had mistakenly wired it to switch off the 12 volt positive to the main fan input (big 10 gauge wire) through a 40 amp relay, but Brian informed me that the controller needs to have the main input connected while the controller is running since it uses active switching to clamp the flyback voltage of the fan. I guess the fan is kind of like a little generator and sends a reverse voltage back though the system. In Brian's words: "What happens is that when you turn the voltage off on a motor is that it will generate a very high reverse voltage. The controller clamps this to ground byway of an active switch. If there's no voltage to the circuit board, the switch can't be activated."

Brian @ DCC has been very helpful and quickly answered many e-mails of my stupid questions.

__________________
~Dale~

93 4X4 ext-cab, auto, SR5, 3.4 V6, supercharged, 2.1" pulley, URD fuel mods, Aquamist WI, IPT valve body mod, dual cases, 4" superlift front, Alcan springs rear, 33 BFG MT, ARB locked front & rear, 5.29 US Gears, RB 1" Body Lift, 1.5" ball joint spacers, manual hubs, TJM T-17, Warn m8000.