Electrical Gurus Help - Stand Alone fan controller system.
#1
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I am doing an LQ9 retrofit into my 65 Skylark. The car will be carbureted, so there will be no ECM to control the cooling fans. I need to design a set up that can handle the amperage draw of the Taurus fan, can control both fan speeds and have an override for the air conditioning once it is added.
There are a few proprietary solutions out there, but I prefer something that has off the shelf parts to make it easily serviceable.
Texas Industrial Electric offered a design solution. Have a look at this diagram and tell me if you think this is the way to go.
There are a few proprietary solutions out there, but I prefer something that has off the shelf parts to make it easily serviceable.
Texas Industrial Electric offered a design solution. Have a look at this diagram and tell me if you think this is the way to go.
#2
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That will work, but seems unnecessarily complicated. Why not just two relays. One for high speed setting, one for low speed. You can trigger them with temp probes in the radiator or switches mounted in the cyl head or any water jacket/rad hose. Several thermal switches at various turn on temps are available from summit, just search for fan switch and pick what you need
#3
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That will work, but seems unnecessarily complicated. Why not just two relays. One for high speed setting, one for low speed. You can trigger them with temp probes in the radiator or switches mounted in the cyl head or any water jacket/rad hose. Several thermal switches at various turn on temps are available from summit, just search for fan switch and pick what you need
#4
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what make of fans are you using, is it one fan or two, and do they have an actual high speed and low speed input to them like in your diagram?
If you have two fans that are similar to those on the 98-02 f-body, they are just a DC motor with one positive lead and a ground, unlike your diagram which shows a low speed input and a high speed input. Is there some control circuit with your fans?
the way the f-body fans work are with 3 relays, which allow the fans to be run in low speed by running the two in a series circuit so each fan only sees 6 to 7 volts (system voltage / 2) or in high speed by running them in parallel and each fan gets full voltage. I can send you the wiring diagram if you want it, it's detailed in my service manual.
your diagram seems wrong to me, that 5-prong relay on the left doesn't make sense and i don't see the fans running at low speed via the low speed temp sender controlling it, or the fans will be on low all the time.
And with the way the f-body fans work there's two wires controlling the speed for low and high. these two wires run from the the fan relays to the pcm, and the pcm grounds just the low speed wire to make the fans run in series. But to run the fans on high speed it has to ground both the low speed and high speed wires going to the relays. If it grounds just the high speed wire and not the low, then only one radiator fan runs on high speed and the other one doesn't run.
For operation of the AC and wanting the radiator fans to run when the AC is running, you would do this wiring logic prior to the low and high speed temp sender.
I can help with wiring but you have to let me know the make/model of the fans you are using so i can look up how they get wired. The relays to do all this can be off the shelf and cheap, hardest part will be figuring out how you want to house all this but you can buy a fuse box from jegs that will hold 3 or more relays. And if you want this to be all automatic you would want to find a switching temp sender that operates by having continuity above a certain temperature and be an open circuit otherwise, and you would need 2 one for low speed temp and one for high. If your ok with manual operation then that's easily done with a 2 position toggle switch, or you can do one temp sender to do low speed control automatically and have a manual switch to do high speed.
If you have two fans that are similar to those on the 98-02 f-body, they are just a DC motor with one positive lead and a ground, unlike your diagram which shows a low speed input and a high speed input. Is there some control circuit with your fans?
the way the f-body fans work are with 3 relays, which allow the fans to be run in low speed by running the two in a series circuit so each fan only sees 6 to 7 volts (system voltage / 2) or in high speed by running them in parallel and each fan gets full voltage. I can send you the wiring diagram if you want it, it's detailed in my service manual.
your diagram seems wrong to me, that 5-prong relay on the left doesn't make sense and i don't see the fans running at low speed via the low speed temp sender controlling it, or the fans will be on low all the time.
And with the way the f-body fans work there's two wires controlling the speed for low and high. these two wires run from the the fan relays to the pcm, and the pcm grounds just the low speed wire to make the fans run in series. But to run the fans on high speed it has to ground both the low speed and high speed wires going to the relays. If it grounds just the high speed wire and not the low, then only one radiator fan runs on high speed and the other one doesn't run.
For operation of the AC and wanting the radiator fans to run when the AC is running, you would do this wiring logic prior to the low and high speed temp sender.
I can help with wiring but you have to let me know the make/model of the fans you are using so i can look up how they get wired. The relays to do all this can be off the shelf and cheap, hardest part will be figuring out how you want to house all this but you can buy a fuse box from jegs that will hold 3 or more relays. And if you want this to be all automatic you would want to find a switching temp sender that operates by having continuity above a certain temperature and be an open circuit otherwise, and you would need 2 one for low speed temp and one for high. If your ok with manual operation then that's easily done with a 2 position toggle switch, or you can do one temp sender to do low speed control automatically and have a manual switch to do high speed.
#5
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what make of fans are you using, is it one fan or two, and do they have an actual high speed and low speed input to them like in your diagram?
If you have two fans that are similar to those on the 98-02 f-body, they are just a DC motor with one positive lead and a ground, unlike your diagram which shows a low speed input and a high speed input. Is there some control circuit with your fans?
the way the f-body fans work are with 3 relays, which allow the fans to be run in low speed by running the two in a series circuit so each fan only sees 6 to 7 volts (system voltage / 2) or in high speed by running them in parallel and each fan gets full voltage. I can send you the wiring diagram if you want it, it's detailed in my service manual.
your diagram seems wrong to me, that 5-prong relay on the left doesn't make sense and i don't see the fans running at low speed via the low speed temp sender controlling it, or the fans will be on low all the time.
And with the way the f-body fans work there's two wires controlling the speed for low and high. these two wires run from the the fan relays to the pcm, and the pcm grounds just the low speed wire to make the fans run in series. But to run the fans on high speed it has to ground both the low speed and high speed wires going to the relays. If it grounds just the high speed wire and not the low, then only one radiator fan runs on high speed and the other one doesn't run.
For operation of the AC and wanting the radiator fans to run when the AC is running, you would do this wiring logic prior to the low and high speed temp sender.
I can help with wiring but you have to let me know the make/model of the fans you are using so i can look up how they get wired. The relays to do all this can be off the shelf and cheap, hardest part will be figuring out how you want to house all this but you can buy a fuse box from jegs that will hold 3 or more relays. And if you want this to be all automatic you would want to find a switching temp sender that operates by having continuity above a certain temperature and be an open circuit otherwise, and you would need 2 one for low speed temp and one for high. If your ok with manual operation then that's easily done with a 2 position toggle switch, or you can do one temp sender to do low speed control automatically and have a manual switch to do high speed.
If you have two fans that are similar to those on the 98-02 f-body, they are just a DC motor with one positive lead and a ground, unlike your diagram which shows a low speed input and a high speed input. Is there some control circuit with your fans?
the way the f-body fans work are with 3 relays, which allow the fans to be run in low speed by running the two in a series circuit so each fan only sees 6 to 7 volts (system voltage / 2) or in high speed by running them in parallel and each fan gets full voltage. I can send you the wiring diagram if you want it, it's detailed in my service manual.
your diagram seems wrong to me, that 5-prong relay on the left doesn't make sense and i don't see the fans running at low speed via the low speed temp sender controlling it, or the fans will be on low all the time.
And with the way the f-body fans work there's two wires controlling the speed for low and high. these two wires run from the the fan relays to the pcm, and the pcm grounds just the low speed wire to make the fans run in series. But to run the fans on high speed it has to ground both the low speed and high speed wires going to the relays. If it grounds just the high speed wire and not the low, then only one radiator fan runs on high speed and the other one doesn't run.
For operation of the AC and wanting the radiator fans to run when the AC is running, you would do this wiring logic prior to the low and high speed temp sender.
I can help with wiring but you have to let me know the make/model of the fans you are using so i can look up how they get wired. The relays to do all this can be off the shelf and cheap, hardest part will be figuring out how you want to house all this but you can buy a fuse box from jegs that will hold 3 or more relays. And if you want this to be all automatic you would want to find a switching temp sender that operates by having continuity above a certain temperature and be an open circuit otherwise, and you would need 2 one for low speed temp and one for high. If your ok with manual operation then that's easily done with a 2 position toggle switch, or you can do one temp sender to do low speed control automatically and have a manual switch to do high speed.
#6
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OR, you could use one of these guys: http://www.summitracing.com/parts/DER-16749/
![](http://www.streetperformance.com/ART/PRODUCTS/100618/derale-cooling-products-16749.jpeg)
It's adjustable, relay and temp sensor is built in. Easy to wire. A/C override (could also be used as a manual override) as well as dual fan option(depending on the current draw fromt he fan[which is pretty high on those Taurus fans IIRC]) I used this same thing on my S-10 with the Taurus fan. I only hooked up the high speed, as I found that was good enough, and if you have no where to thread the temp sensor into, you can get one of those radiator hose tee's like this:
![](http://www.proracestore.com/images/products/6037_hdr_2.jpg)
And for about $40, you cant beat it
EDIT:: I fail at reading your last post....glad you got it figured out
![](http://www.streetperformance.com/ART/PRODUCTS/100618/derale-cooling-products-16749.jpeg)
It's adjustable, relay and temp sensor is built in. Easy to wire. A/C override (could also be used as a manual override) as well as dual fan option(depending on the current draw fromt he fan[which is pretty high on those Taurus fans IIRC]) I used this same thing on my S-10 with the Taurus fan. I only hooked up the high speed, as I found that was good enough, and if you have no where to thread the temp sensor into, you can get one of those radiator hose tee's like this:
![](http://www.proracestore.com/images/products/6037_hdr_2.jpg)
And for about $40, you cant beat it
EDIT:: I fail at reading your last post....glad you got it figured out