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Electric Fan Wiring assistance needed.

Electric Fan Wiring assistance needed.
BrockGrimes

BrockGrimes

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Gentle folks preferably wiring guru's does this electric fan wiring scheme work?
Any changes recommendations? I could also just use a lighted switch instead?
5amp fuse for the 12v ignition side?
Fusable link or 30amp fuse or bigger?
10-12 GA for power and grounds
12-16 for others?

FanWiring2_zpsafa5b5e6.webp
 
looks good..I would probably put the light on the other side of the manual override switch..where it is now the light would be on even if the switch was turned off
 
I am afraid that the second motor circuit does not work for me. It looks to be energizing the 2nd motor through the coils of the relays rather than the contact. Way too much current to pull this off for very long.

Needs a temperature switch to ground the relay coils, where the light is now. as manual switches go I think the only reason to turn it off is a water crossing and if I go in that deep I do not think the fan will run for long when the redeator hits the cool water, just saying.

This next part is kind of hard to follow, not sure I follow it myself but here goes.
The horizontal line from the 2nd motor and the line between the 1st motor and term 87 should go to the line to the 2nd motor and the line from that point to the indicator light line should go away. As is the contacts form both relays are both powering the 1st motor and the current drawn by the second motor is passing through the coil which only has 18 ga wire and is not made to carry 9 or 10 amps plus end rush.



Bosh 40amp relay sockets are wired with 14 ga wire, which will carry 40 amps 12V dc. which is actually a little more than the relay contacts are rated for.

the coil wire is 18 ga, I think. and don't forget the fuzes on the line power from the battery as close to the battery as possible so it protects as much wire as possible. 15, maybe 20amps those fans should not draw more than 9 or 10 amps dc.
Automatic reset circuit beakers are totally off the hook.

Let me know if you need supplier sites for relays and everything but Waytec should be able to cover what ever you need.

I thought you did this already.:cool:





these handle two fans, high and low beam and aux lights and the horn.
 
I read the diagram as only having 1 fan with 2 relays wired in parrallel in case one of them went out and the other large circle being a toggle switch to manually turn it off when desired..if that is correct then it will work..You could add a thermostat controlled switch if desired..I would add it in series with the toggle switch and then parrallel another toggle switch with the thermal switch in case you wanted/needed to bypass it..
 
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Pete I thought you were going to use the Toyota two fan set up. the Concourse?
 
This is the best information on Bosh relays I have seen. You can do a lot of cool things with Bosh relays. I am tempted by the "flash headlights left and right". I am sure that would be all sorts of fun.

http://dlcparts.com/images/BoschGuide.pdf
 
BrockGrimes said:
Gentle folks preferably wiring guru's does this electric fan wiring scheme work?
Any changes recommendations? I could also just use a lighted switch instead?
5amp fuse for the 12v ignition side?
Fusable link or 30amp fuse or bigger?
10-12 GA for power and grounds
12-16 for others?

FanWiring2_zpsafa5b5e6.webp
Click to expand...

I see several issues looking at your schematic.

My first an largest question for you is why two relays? Looking at how you have them wired everything on those relays are the same electric point. If you were to wire it up according to your schematic and then unplugged either out you would still have a functioning circuit. Is this in case one burns out? I guess in theory you are splitting the amperage draw half between the two relays which would reduce the chance of burning one out but I have a 30 amp fuse on my F150 and both fans run off it and it has never blown the fuse and most relays are rated at 40 amps. What I would do is but a 25-30 amp fuse instead of using fusable link

My second observation is your "ign on source" You indicate you prefer this to the acc source so that it wont run in acc. On the cj wiring these are one and the same. so in your wiring diagram this setup will turn on the fan as soon as you turn the key even if you dont hit the starter unless you have your manual switch off.

Third, as stated by another member your indicator light needs to be moved to between the override and the ground so that it will turn off when you deactivate the fan.

Finally, The activation source is constant in this diagram... You really need to add a switch that is activated by a thermostat. You don't want the fan kicking on till your thermostat opens up and hot coolant starts flowing through the radiator.

I suggest that you just buy a fan controller from the autoparts store. THey are universal and run about 20-50 bucks. I strongly suggest you look at the flexalite variable speed controller which runs 90-120 dollars depending on where you get it. It is easy to wire, has a computer that controls how much amperage the fans draw depending on the temp of the engine, it has the provisions for an indicator light, as well as provisions for a manual shutoff. I use this one in all my electric fan conversions (except with my current cj because the fans are controlled by the ecms).

I edited your schematic in paint to move the indicator light and also show the circuit with the second relay deleted.
 
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I picked up a 80ish amp constant duty solenoid for my contour fan. I wired it with 10 gauge wire. I run the ground for the relay to a 185 degree on coolant switch. The ground wire goes from the switch to my manual shut off switch (mounted upside down in my dash so switch down is on) then out to my relay ground. By doing it this way the motor is allowed to heat up to operating temp. Once it hits the 185 the switch ground out the relay allowing it to close and turn the fan on. If I need to shut the fan off to play in the water I flip my manual over ride switch to the up position and and it breaks the ground turning the fan off.

And like stated earlier your light is wired wrong. it should be wired to one side of the switch or the other. if you want to wire to the side that has power to it thats fine but dont ground it. power should go into the light then out to the switch. I would wire it on the ground side. Ground in then on terminal then out to the ground source.
 
I believe that the 2 relays is just a safety feature in case one fails..I don't use 2 on mine but there is no harm in it.
 
3681901245dc494588038b4e1c6537f890f017b9_large.webp
 
electric-motor-icon-and-symbol-thumb27014494.webp
 
Jimbos76cj said:
And like stated earlier your light is wired wrong. it should be wired to one side of the switch or the other. if you want to wire to the side that has power to it thats fine but dont ground it. power should go into the light then out to the switch. I would wire it on the ground side. Ground in then on terminal then out to the ground source.
Click to expand...

Doing it that way, if the bulb burned out it would stop the operation of the fan. Also the entire amperage load would then be pushed through the light as well.
 
ThisGuyUKnow said:
Doing it that way, if the bulb burned out it would stop the operation of the fan. Also the entire amperage load would then be pushed through the light as well.
Click to expand...

exactly..the indicator light should not be wired in series with the circuit..it should be wired in parallel, after the switch,with it's own ground
 
harleydragon said:
I believe that the 2 relays is just a safety feature in case one fails..I don't use 2 on mine but there is no harm in it.
Click to expand...

No there is no harm in it but I believe it is best to apply KISS when doing DIY wiring. The liklihood the relay will burn out is low if you use a quality relay rated for 30 AMPS or more. You don't want the relay to be the weak point in the system that is what fuses or fusable link is for.
 
ElectricFanSportruk.webp

I like this one for 2 speed or 2 fans but it needs 2 thermostats.

fan_wiring.webp

DualFanWiringDiagram01.webp
 
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please tell us where a temperature activated variable speed motor controller can be found.:D
 
IOPort51 said:
please tell us where a temperature activated variable speed motor controller can be found.:D
Click to expand...

I dont know about a variable speed motor, but I linked the controller in my last post. If achieves differenct fan speeds by limiting the amount of amps the motor(s) are pulling starts at about 60% at the low temperature and up to 100% if the temp continues to rise. I rarely see it run longer than a a minute even in heavy traffic on my 5.4
 
harleydragon said:
exactly..the indicator light should not be wired in series with the circuit..it should be wired in parallel, after the switch,with it's own ground
Click to expand...

ThisGuyUKnow said:
Doing it that way, if the bulb burned out it would stop the operation of the fan. Also the entire amperage load would then be pushed through the light as well.
Click to expand...

Hmmm .. Guess I got a new task ahead of me.. Little bit of rewiring for some bulbs. Thanks for the correction
 
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