Bible Cooling Fan Tech

Malburg114 said:
I’m not necessarily following on how to wire this. Forgive my ignorance as wiring is not my forte

I currently have a msd relay block, link below

Currently, the first two relays are for each fan and the relay block has fuses built into it as well.

10 gauge positive wires run to the output side of the relays from the fans and the input is the Holley trigger wires. The Holley is currently a negative trigger.

So my thought is to leave the positive wires from the brushless fans go to the relay block. Run the pwm wire from the fan to a separate plug with the Holley input wires which get changed to the pwm- signal. And then “close” the relay by running a ground wire on the input side of the relay block to the chassis. Instead of the Holley sending a ground signal, just have a ground wire to the chassis which in my head would mean the fans have constant power?

If that complicates it to much or if a relay isn’t needed, I can run the power wires to a positive block off the battery switch and put fuses inline. Using the relay block just makes it easy because I’m not changing much. Just adding a plug.
Click to expand...
Given the cost and fragility of solid state relays I would just route the fan power around those relays, and use the relays for something else.

The 70a relays I use for fans are 1/10 the price of that MSD unit.
 
Just got another Broce 850w fan for $67 shipped, it was removed from the shroud already which is perfect for my Suburban

1775654083551.png
 
CarterKraft said:
Just got another Broce 850w fan for $67 shipped, it was removed from the shroud already which is perfect for my Suburban

1775654083551.png
Click to expand...
And because I'm a lazy dumb ass I ordered another fan that is too big for the core...
66' C10 has a 17.5" tall core 23" wide so the 19" exactly diameter fan wheel is 1.5" larger than the core height.
On the El Camino I just left some fan blade hanging over the top/bottom of the core, not ideal but I didn't care too much at the time.

On the burb I'm trying to do a better job so I am thinking I just make the shroud tapered back to the core or just make it square and seal it to the tanks with some edge trim.

Any opinions on this?
1776273465173.png
 
CarterKraft said:
And because I'm a lazy dumb ass I ordered another fan that is too big for the core...
66' C10 has a 17.5" tall core 23" wide so the 19" exactly diameter fan wheel is 1.5" larger than the core height.
On the El Camino I just left some fan blade hanging over the top/bottom of the core, not ideal but I didn't care too much at the time.

On the burb I'm trying to do a better job so I am thinking I just make the shroud tapered back to the core or just make it square and seal it to the tanks with some edge trim.

Any opinions on this?
1776273465173.png
Click to expand...
Shrouds like that are common with small coolers when trying to fit the next size larger fan.
Be sure to put drain holes if you form a pocket.
 
Ghetto Fab. said:
Well, I got it working last night the way I think it should work. Readjusted things to be the standard Bosch PWM style and then had to reset the hi/lo set points again. It stays off now until it hits the low setpoint. The low setpoint is set at 200deg. This should allow the system to cool on the highway without the fan coming on. Just idling in the shop it will kick on at 200 then run for a bit and shut off. I'm surprised at the lag in the system. Motor hits 205 before it gets cooler coolant, then drops down to 195 turning the fan off. Should get a windshield in it today so hopefully soon I can drive it around and see what it does.
Click to expand...
What settings did you end up using on the widgetman fan controller? I tried the 100hz most Volvo settings and it is not working. on on off on for 1-4.

Google says the fan is supposed to run full speed with no input hz input. Mine does not do that either.
 
Chevy volt fans wired and working with the Holley terminator x. Main thing I forgot was to add a fuse or breaker between the positive. It goes to my battery switch. Do I need to add one? Seems some do and some don’t.

Cut down the plastic shroud to fit better
IMG_2202.jpeg
IMG_2200.jpeg
IMG_2198.jpeg
IMG_2199.jpeg
 
Malburg114 said:
Chevy volt fans wired and working with the Holley terminator x. Main thing I forgot was to add a fuse or breaker between the positive. It goes to my battery switch. Do I need to add one? Seems some do and some don’t.

Cut down the plastic shroud to fit better
Click to expand...

The new setup looks badass. I'm curious to hear how it will treat ya, but I think it's a massive upgrade over the previous fans. I'm personally a fan of the route you took deleting the relays because of the way brushless fans manage things, but I do think a safety device like a fuse or circuit breaker is needed. Just for protection if the worst case were ever to happen like a direct short etc

In my own case I used a self resetting circuit breaker on the positive wire near the battery so it always has power, it's protected, but I don't have to carry any fuses. Granted I used generic import circuit breakers but I figure better than nothing
 
+1 on adding a fuse.
Especially since they are exposed in a rollover.

Test out the cooling power yet?
 
Outahand said:
What settings did you end up using on the widgetman fan controller? I tried the 100hz most Volvo settings and it is not working. on on off on for 1-4.

Google says the fan is supposed to run full speed with no input hz input. Mine does not do that either.
Click to expand...
Many won't go full speed with no signal, they won't do anything at all.
I don't really like that but it is what it is.

Also side note and we may have already covered this but is that fan motor brushed?
Its hard to tell from the pix but it looks like a variable speed brushed fan, and IMO that doesn't add much to your cooling stack besides variable speed.

At any rate its a Bosch fan I think, so per this there are only 2 Bosch options, again that fan is not brushless so this may not apply.

1776538229126.png
 
Outahand said:
What settings did you end up using on the widgetman fan controller? I tried the 100hz most Volvo settings and it is not working. on on off on for 1-4.

Google says the fan is supposed to run full speed with no input hz input. Mine does not do that either.
Click to expand...
per that chart you should be ON OFF OFF OFF, if I am seeing that right.
 
Brushless fans should be on a battery kill switch so they don’t drain the battery when stored or always run a charger maintainer.
Fuse or breaker to protect the wire but not the fan. The fan should fault out and reset if something goes wrong.
No relay is needed.
 
Malburg114 said:
Chevy volt fans wired and working with the Holley terminator x. Main thing I forgot was to add a fuse or breaker between the positive. It goes to my battery switch. Do I need to add one? Seems some do and some don’t.

Cut down the plastic shroud to fit better
Click to expand...
e5b152be-bc2c-4203-83d5-ae1faf404381.jpg

I put a Blue Sea 70a breaker on my 850w fan. Like others said, a dead short with the size of these wires is a lot of heat prior to burning through.
 
the bosch/volvo fan is indeed brushless, and should run on 100hz pwm frequency, and no it doesn't go full speed when there's no pwm signal. from my experience playing around with oem brushless fans only the mercedes fans turn full speed when theres no pwm signal, they also require a 12v signal to run(second small wire next to pwm wire that other manufacturers dont use). and just a tip, the bosch motor and fan blades are balanced as a unit, BMW also used this fan motor but with different blade design in the 3 series, if you take the blade off the motor make sure to put it back in the same orientation cause it will vibrate like crazy if it's off 120 degrees. also frequency in which these fans operate depends on the car they came from and not who made the fan. I have 2 identical BROSE 600w fans, one from bmw and one from mercedes. The bmw one runs at 100hz, reverse duty cycle and doesnt use the 12v signal wire. The mercedes one runs at 11 hz, "normal" duty cycle, and needs 12v signal wire.
 

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Magicpotatoes said:
the bosch/volvo fan is indeed brushless, and should run on 100hz pwm frequency, and no it doesn't go full speed when there's no pwm signal. from my experience playing around with oem brushless fans only the mercedes fans turn full speed when theres no pwm signal, they also require a 12v signal to run(second small wire next to pwm wire that other manufacturers dont use). and just a tip, the bosch motor and fan blades are balanced as a unit, BMW also used this fan motor but with different blade design in the 3 series, if you take the blade off the motor make sure to put it back in the same orientation cause it will vibrate like crazy if it's off 120 degrees. also frequency in which these fans operate depends on the car they came from and not who made the fan. I have 2 identical BROSE 600w fans, one from bmw and one from mercedes. The bmw one runs at 100hz, reverse duty cycle and doesnt use the 12v signal wire. The mercedes one runs at 11 hz, "normal" duty cycle, and needs 12v signal wire.
Click to expand...
Factory plug does not even have a wire in the second position. I would think that means it is not needed?

IMG_7221.jpeg
 
I meant to say Mercedes fans require the 12v signal to run, all the other ones I tested don’t need it. As far as trying to diagnose your fan, I’d get a cheap pwm signal generator from amazon to try to turn it on maybe you can rule out the fan being dead
 
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