Another mark 8 fan question
Thread Starter
Drifting
Joined: Jun 2005
Posts: 1,523
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From: grand prairie texas
Another mark 8 fan question
I just bought a mark 8 fan assembly from a friend. fan motor #F3LU-8K621-AA. It has 3 wires from the connector the positive wire marked by plus on connector is light blue. The other 2 wires are black. Testing this fan the one black wire I ground the fan runs at high speed. When I unground the one black wire and ground the other black wire the fan does nothing. Can someone help me in the proper understanding of the operation of this fan? Is this a high speed only fan? This is a winter coming project. I believe it is from 93-96 lincoln
Le Mans Master
Joined: May 2006
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From: League City Tx
The other "black"'wire actually has a red tracer on it...that is also a power wire so if you ground it, the fan won't run. So ground the all black wire and use either the blue or blk/red wire for power. I did not use the blue wire at all. I tried all wiring combos. Mine only has one speed...which I assume is high. I think you need the controller for an actual dual speed application.
I'm just gonna run mine on high all the time.
I'm just gonna run mine on high all the time.
Le Mans Master
Joined: Dec 2006
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From: Oquirrh Mountains
St. Jude Donor '09
One is ground, one is high speed, one is low speed, but I don't recall which is which by color. The high speed wire was one gauge larger than the low speed wire on the ones I've seen though so take a look at that.
MAKE SURE and only use the high speed wire. If you connect both high and low to your power source, the fan motor will burn up.
MAKE SURE and only use the high speed wire. If you connect both high and low to your power source, the fan motor will burn up.
Thread Starter
Drifting
Joined: Jun 2005
Posts: 1,523
Likes: 1
From: grand prairie texas
One is ground, one is high speed, one is low speed, but I don't recall which is which by color. The high speed wire was one gauge larger than the low speed wire on the ones I've seen though so take a look at that.
MAKE SURE and only use the high speed wire. If you connect both high and low to your power source, the fan motor will burn up.
MAKE SURE and only use the high speed wire. If you connect both high and low to your power source, the fan motor will burn up.
Thread Starter
Drifting
Joined: Jun 2005
Posts: 1,523
Likes: 1
From: grand prairie texas
I found a 95 lincoln mark 8 wiring diagram and it shows the wiring as the blue is the positive and one black is the ground and the black wire shows not to be used for that year application. I hooked the fan up to my car battery today and with my fluke amp clamp the start up amps spiked momentarly to 96 amps and constand running amps are 26. I am running the old volvo fan on my car now and I have a 75 amp relay and a 40 amp resettable circuit breaker. Will this combo be alright for the amps I just quoated. Also I am running 10ga wire.
Le Mans Master
Joined: May 2006
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From: League City Tx
Did you try powering it up with the blk/red wire and see what it did?
I am not using the blue for power. I read somewhere that blue was for low speed and blk/red was for high. I tried mine both ways and it ran the same speed. I ended up using both black wires. I have not road tested it but the fan does work.
I am not using the blue for power. I read somewhere that blue was for low speed and blk/red was for high. I tried mine both ways and it ran the same speed. I ended up using both black wires. I have not road tested it but the fan does work.
Thread Starter
Drifting
Joined: Jun 2005
Posts: 1,523
Likes: 1
From: grand prairie texas
Did you try powering it up with the blk/red wire and see what it did?
I am not using the blue for power. I read somewhere that blue was for low speed and blk/red was for high. I tried mine both ways and it ran the same speed. I ended up using both black wires. I have not road tested it but the fan does work.
I am not using the blue for power. I read somewhere that blue was for low speed and blk/red was for high. I tried mine both ways and it ran the same speed. I ended up using both black wires. I have not road tested it but the fan does work.
Le Mans Master
Joined: May 2006
Posts: 9,993
Likes: 1,136
From: League City Tx
My fan has only got three wires coming from the harness. Light blue and 2 black wires. Tried hooking up different ways will only run single high speed which is the way I want it. My lincoln fan diagram shows only 2 wires being used and other black wire not used. What amp relay and fuse are you using?
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Race Director
Joined: Mar 2006
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From: Florida
There were several different part numbers from Ford.
The early fans had a red/black, black and blue.
Red/black was high speed, blue was low speed (a/c) and black ground
On some later fans the blue was not internally connected and the fan was variable speed, controlled by the ECM.
The early fans had a red/black, black and blue.
Red/black was high speed, blue was low speed (a/c) and black ground
On some later fans the blue was not internally connected and the fan was variable speed, controlled by the ECM.
