manual fan switch installation.
Thread Starter
Le Mans Master
Joined: Apr 2000
Posts: 5,713
Likes: 105
From: Manassas VA
manual fan switch installation.
Where are you going through the firewall at? Im wanting to put one in for this weekend and was wondering where the easiest place to pass through the firewall is and where you mounted the switch.
Le Mans Master
Joined: Nov 2000
Posts: 8,745
Likes: 31
From: SE TN
Re: manual fan switch installation. (Red 86 4+3)
I mounted mine in my center console. Hidden and very easy to turn on and off.
I ran the wires through the fire wall under the driver side dash. (Below steering wheel) There is a few wire bundles that run through the fire wall and I just fed the wires through there. Nothing too dificult and everything is hidden pretty good.
I ran the wires through the fire wall under the driver side dash. (Below steering wheel) There is a few wire bundles that run through the fire wall and I just fed the wires through there. Nothing too dificult and everything is hidden pretty good.
Racer
Joined: Sep 2001
Posts: 314
Likes: 0
From: Forest Hill MD
Re: manual fan switch installation. (Red 86 4+3)
I received the kit I ordered from Mid America yesterday. In reading through the instructions, they suggested to go through the grommet that the cruise control goes through to get to the engine bay.
Burning Brakes
Joined: May 2002
Posts: 986
Likes: 99
From: Collegeville PA
Re: manual fan switch installation. (Red 86 4+3)
I did mine about a week ago. There's a grommet behind the battery that comes into the car at the top left corner under the drivers kick panel. Make sure you use at least the same guage wire as the circuit, fuse it, and get a heavy duty switch, like 20A. I mounted mine on the kick panel right behind the thing that you plug into to get the codes. I forget the name of it, but its on the right hand side towards the front. This way there's no chance of hitting it by accident, and you can't see it. I think I had to use a 30A fuse. The 20's keps blowing, and I burnt out the first toggle switch. Works gerat now. All this came after I drove 3 hrs in traffic to get to the track. Car was hot (225) all night. Should have been 160 - 180. Wish I had the switch then. Route the wires in existing loom for cleaner look and solder the connections if possible.
Good Luck!
Good Luck!
Racer
Joined: Jun 2001
Posts: 376
Likes: 0
From: Cleveland, OH, USA
Re: manual fan switch installation. (Triple Black 88)
Jim and Triple Black routed theirs the same way I did. That is the cruise control grommet. I mounted my switch on the top left corner of the carpeted under dash panel, right below the fog lamp switch. That way I can reach it from outside the car.
Thread Starter
Le Mans Master
Joined: Apr 2000
Posts: 5,713
Likes: 105
From: Manassas VA
Re: manual fan switch installation. (Triple Black 88)
Make sure you use at least the same guage wire as the circuit, fuse it, and get a heavy duty switch, like 20A. I mounted mine on the kick panel right behind the thing that you plug into to get the codes. I forget the name of it, but its on the right hand side towards the front. This way there's no chance of hitting it by accident, and you can't see it. I think I had to use a 30A fuse. The 20's keps blowing, and I burnt out the first toggle switch. Works gerat now. All this came after I drove 3 hrs in traffic to get to the track. Car was hot (225) all night. Should have been 160 - 180. Wish I had the switch then. Route the wires in existing loom for cleaner look and solder the connections if possible.
Good Luck!
Good Luck!
Le Mans Master
Joined: Dec 1999
Posts: 8,540
Likes: 1
From: And on the fifth day, subpoenas were served to Obama senior staff
Re: manual fan switch installation. (Red 86 4+3)
Silly that MAD has you run fan current through that switch, dangerous.
Switch should just ground the relay, minimal current - much safer. No fuse necessary, any switch will due.
Switch should just ground the relay, minimal current - much safer. No fuse necessary, any switch will due.
Burning Brakes
Joined: May 2002
Posts: 986
Likes: 99
From: Collegeville PA
Re: manual fan switch installation. (Red 86 4+3)
Pete and Red, let me clarify some things. I am running the fan power thru the toggle switch...on purpose. Like Pete said, you can wire it up to close the relay selenoid, use any switch and it will work fine. But my brother had a fan relay crap out on him in the middle of no where one time, overheated and was stranded. By running the power thru the switch, it also serves as a backup incase the relay gives out, you can still control the fan. BTW, I picked up the switch and wire from Sears Hardware so you don't need to order (and wait) for a kit.
I'm not 100% sure about this, but wiring to the relay may only let you turn the fan on and off with the key on (Dash lit up). Pete could clarify that. My way works with the car off. Ideal for the track. If hot, "Just set it...and forget it" check out a few races come back and all cooled off. Let me know if you have any questions. Also keep us posted when you get it hooked up.
I'm not 100% sure about this, but wiring to the relay may only let you turn the fan on and off with the key on (Dash lit up). Pete could clarify that. My way works with the car off. Ideal for the track. If hot, "Just set it...and forget it" check out a few races come back and all cooled off. Let me know if you have any questions. Also keep us posted when you get it hooked up.
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Le Mans Master
Joined: May 2002
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From: 10.70 @ 124mph, Stock Bottom End @ 3620lbs, ECS Racing Team Member. The 1st NMCA LSX Index Rumble World Champion. 2011,12,13 Champion
Re: manual fan switch installation. (Red 86 4+3)
I drilled a hole to the right of the brake booster, Then I was able to run the wire inside the car. I had to drop the lower panel under the drivers side of the dash board. everybody has a different location to mount there switch. I placed mine on the cover that had to be removed to get the wires from the fire wall. It can not be seen when the door is open. It is out of the way and no way off turning it on by accident. It is not hard for me to reach to turn it on. 
Drifting
Joined: Aug 2001
Posts: 1,550
Likes: 27
From: Minneapolis MN
Re: manual fan switch installation. (Triple Black 88)
Behind the battery there is an existing ground. You'll need an extention to get to it, but its not to bad.
Burning Brakes
Joined: May 2002
Posts: 986
Likes: 99
From: Collegeville PA
Re: manual fan switch installation. (FlyboyZR1)
I made a mistake. The area behind the battery is NOT the ground, its the (constant) hot wire. That goes to the one side of the switch (fused), and the wire from the other side of the switch goes to fan's hot wire, after the relay.
PeteL, what did you mean when you said that this setup was "dangerous"?
PeteL, what did you mean when you said that this setup was "dangerous"?
Instructor
Joined: Jun 2002
Posts: 177
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From: Escondido CA
Re: manual fan switch installation. (Triple Black 88)
The switch has to be pretty heavy duty to hold the amperage for one. Also, If you fan locks up or the wire shorts on the outgoing leg of the switch it will burn all the way back to the battery. This means you could catch the car on fire in the dash. You will have to fuse this thing with either a maxi fuse or a circuit breaker as close to the power source as possible. Be very carefull not to let it rub a ground ANYWHERE--insulate and route it well. Then it will be ok.
Le Mans Master
Joined: Dec 1999
Posts: 8,540
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From: And on the fifth day, subpoenas were served to Obama senior staff
Re: manual fan switch installation. (Triple Black 88)
Grounding the fan relay is not dangerous. This is all anybody should do.
Switching the main +12V feed to the fan with a manual switch run in the cabin is dangerous and unnecessary. This is especially true with an electric motor (fan motor). In rush current is very high at turn on, and a voltage spike will occur at turn off. The switch will wear and eventually be high resistance and could burn up even with normal fan current, and without blowing the fuse. This setup is doomed to failure. You need to avoid high current lines as much as possible, that is why relays are used. Fan relay failure is rare, and usually only when the fan is failing. You could always carry a spare relay. High current switch should be rated at 1.5 X inrush current which I would guess a 50A switch might be good enough for a while. But I would just use a cheap switch to ground the relay and avoid any problems.
[Modified by PeteL, 8:38 AM 6/7/2002]
Switching the main +12V feed to the fan with a manual switch run in the cabin is dangerous and unnecessary. This is especially true with an electric motor (fan motor). In rush current is very high at turn on, and a voltage spike will occur at turn off. The switch will wear and eventually be high resistance and could burn up even with normal fan current, and without blowing the fuse. This setup is doomed to failure. You need to avoid high current lines as much as possible, that is why relays are used. Fan relay failure is rare, and usually only when the fan is failing. You could always carry a spare relay. High current switch should be rated at 1.5 X inrush current which I would guess a 50A switch might be good enough for a while. But I would just use a cheap switch to ground the relay and avoid any problems.
[Modified by PeteL, 8:38 AM 6/7/2002]
Thread Starter
Le Mans Master
Joined: Apr 2000
Posts: 5,713
Likes: 105
From: Manassas VA
Re: manual fan switch installation. (Triple Black 88)
Triple black 88, You are correct about grounding the solonid only works with the ignition switch on. But on your switch you ran, was it a double pole switch? The reason I ask is, I believe, if you run constant power to the toggle switch, you still will need a ground at the motor. Now it you perm. ground the fan motor, then it will run costantly when the car is running. I was thinking about using a double pole relay, and a switch that lights up (so I wont forget to turn it off) since I believe I will need both power and ground to run the fan with the engine off.
Le Mans Master
Joined: Dec 1999
Posts: 8,540
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From: And on the fifth day, subpoenas were served to Obama senior staff
Re: manual fan switch installation. (Red 86 4+3)
Coolant fan and aux fan are always connected to ground. Fan power to relay always hot.
Coolant fan relay and aux coolant fan relay coils are on switched power, so grounding the realy with ignition off will not turn the fan on.
Why not just turn the key on? (not snotty answer, just wonder?)
Coolant fan relay and aux coolant fan relay coils are on switched power, so grounding the realy with ignition off will not turn the fan on.
Why not just turn the key on? (not snotty answer, just wonder?)
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Re: manual fan switch installation. (PeteL)
Burning Brakes
Joined: May 2002
Posts: 986
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From: Collegeville PA
Re: manual fan switch installation. (Red 86 4+3)
Red 86, I did use a double pole switch, but it doesn't light up(No Ground). It sounds like I hooked up my switch for a different reason. I will pretty much only use the manual fan switch at the track, between runs. Last time I went I was up over 200* because of the drive there, and could not get the temp down. I tried letting the car sit, and I also tried turning the key once to get the fan on but it wouldn't. It had to be started. My fan automatically comes on at 180, so I will also put it on while in line for the next run to keep the temp below that so that the temp doesn't reach 180 and kick on the fan at the launch. I'm not saying this is the best way, but it does exactly what I need it to do. My brother had his hooked up for years without a problem. I hope mine does to.
Le Mans Master
Joined: Dec 1999
Posts: 8,540
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From: And on the fifth day, subpoenas were served to Obama senior staff
Re: manual fan switch installation. (Triple Black 88)
Fan will come on if you ground the relay with the ignition turned to on (engine does not need to be running).