If I remember right, I got this off one of the Ford forums...
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Considered to be the most powerful electric fan you can use from either OEM or the aftermarket. It is a Ford 8C607 fan and is advertised as having 2500 CFM on low speed and 4500 CFM on high by most sources. It comes in the 90 to 95 Ford Taurus and Lincoln Mark VIII with the 3.8 litre engine. Is very popular with the Hot Rod and Muscle crowd as well as used in Offroad buggies etc.
The Mark VIII fan has 2 speeds - 3 wires. The outboard black lead (uppermost pin on the motor if you do not have the pigtail) is the ground (negative). The blue lead (lowermost pin on the motor) was used to activate the fan when the AC was turned on (positive). The center lead (also positive) is black. It was activated by engine temp. I understand that using the black/black combo will give you a higher fan speed than the black/blue combo.
3 Leads; 2 are positive (+) leads and 1 is a ground lead.
Lead functions in stock application:
-BLACK Outboard black lead is a GROUND.
+BLACK Center lead is a POSITIVE lead...actuates fan on engine temp.
+BLUE Outboard lead is a POSITIVE lead..actuates fan w/ aircon.
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The Taurus fan is a 17" diameter fan and the MarkVIII is an 18" fan. They share the same motors, and the shrouds are different. The Taurus fan has an angled edge and the MarkVIII is a rectangle shroud.
MarkVIII
1993-96 #F3LY8C607A low speed 1100RPM high speed 1850
1997 #F7LZ8C607AB
1998 #F8LZ8C607AA low speed for 97/98 1800RPM high speed 2225
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The Taurus, T-Bird, and Lincoln e-fans all use the same motor. The only difference is the blade size - 16, 16.5, 17, 17.5, and 18-inch fans and each have the same three wire configuration.
On the newer fans, you might thing you have a problem if you just apply power to each of the Black wires. On the newer fans, the low speed wire is connected to the side of the plastic housing and the second is the high-speed wire. The speed of the newer model fans is controlled 100% by the EMC. The ECM modulates the voltage to the high speed wire and this gives the e-fan its variable speeds. This give the ECM full control of the e-fan from whisper quit to full power for max-cooling. The ECM modulates the water temperature for best performance and fuel economy for the engine.
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