Electric Fans Wiring?

donnie_19

donnie_19

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Joined
Dec 20, 2012
Messages
305
Location
Troy, MO
I have 2 10" electric fans. Didn't get any kind of wiring schematic or wiring hardware. I am using the Holley EFI to control them but will still need to power them and the Holley will provide the signal for when to turn on and off. What kind of kit should I get?
They didn't come with any kind of shroud. Do I really need one or not?
 
the holley will provide the grounding for a relay, not for the motors directly so ign. swithc a 12V to the relay trigger side, and have the groud of it wired to the holley ecufor the power to the fans you need a 12V battery power and you can choose to either relay control the 12V feed or the ground, Drawback on the ground is, if you have a short to ground somewhere else between fan and relay the fan will keep on running regardless of the relay pos.

Why buy a kit? all you need is some wires, fuse holders and relays. Go to the junkyard with some snips and start cutting weatherpack stuff off GM cars for a nice OEM finish.

A shroud does improve the draw through surface of the fans
 
Before you charge the Vintage Air AC system, swap out the binary switch on the acumulator/drier for a trinary switch to control the compressor and a fan. Wire one fan to the ecu temp control. The other fan to a higher temp setpoint by the ecu or adjustable temp sensor AND the trinary switch. You'll be very happy with that setup.
Good fans pull too much current for the stock fuse panel. Wire them through relays to the alternator directly (fused of course).
Get or make a shroud.
 
Garys 68 said:
Before you charge the Vintage Air AC system, swap out the binary switch on the acumulator/drier for a trinary switch to control the compressor and a fan. Wire one fan to the ecu temp control. The other fan to a higher temp setpoint by the ecu or adjustable temp sensor AND the trinary switch. You'll be very happy with that setup.
Good fans pull too much current for the stock fuse panel. Wire them through relays to the alternator directly (fused of course).
Get or make a shroud.
Click to expand...

/\ THIS!!! I bought dual Spals for my car, the shroud is the best I seen....

:bump:
 
I will check the switch I received when I purchased thd VA. Think its a binary. I can make a shroud out of ABS sheet. schematic woud be nice?
 
just buy two GM harnesses from like 90's luminas. Easy to hook up and run thermostatically. Just buy a power junction block from any GM car. Run a battery power feed to your starter and then to the junction block. then run battery power from you juction block to both relays (fused of course). then run a fused ignition feed wire to each relay. then a thermal ground wire to both relays and a a/c ground pressure wire tapped into the thermal wiring. This way a/c or thermal sensor will trigger both fans.

then simply hook the fan wires up and ground the other two fan wires to the fram.

real easy to do, that is how I did it on my 82 vette
 
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The wiring schematic is on the VA website under "trinary switch".

donnie_19 said:
I will check the switch I received when I purchased thd VA. Think its a binary. I can make a shroud out of ABS sheet. schematic woud be nice?
Click to expand...
 
JeffP1167 said:
just buy two GM harnesses from like 90's luminas. Easy to hook up and run thermostatically. Just buy a power junction block from any GM car. Run a battery power feed to your starter and then to the junction block. then run battery power from you juction block to both relays (fused of course). then run a fused ignition feed wire to each relay. then a thermal ground wire to both relays and a a/c ground pressure wire tapped into the thermal wiring. This way a/c or thermal sensor will trigger both fans.

then simply hook the fan wires up and ground the other two fan wires to the fram.

real easy to do, that is how I did it on my 82 vette
Click to expand...

Friends had a Lumina van, and it had a nasty habit of burning up the fan control relay, harness plug also, must have changed it 3x and it had a new fan motor too...so I would stay clear of any of them oval plugged gray color relays, go for the older square types, in fact my blower motor relay is all direct soldered.....no plug....

:gurney:
 
You get new relays, new terminals to crimp on istead of splicing decades old wires, and has a neat clear cover.
You might want to compare the prices of other manufacturers, Painles has a 3 gang on sale for $163.
http://painlessperformance.shptron.com/p/3-pack-relay-bank

mrvette said:
Garys 68 said:
If you need a multi relay panel, try the one below. Very good price and the terminals are very heavy duty.
http://www.haywireinc.com/index.cfm...ategory_id=-1/home_id=-1/mode=prod/prd167.htm
Click to expand...

:hissyfit: 50 bux, bad enough on the Spals...:crylol:

I just do a junkyard raid, for the motor home, I cut a mitsubitchy box and used about 2/3 of it for the relays controlling tons of crap...

:smash::hijack:
Click to expand...
 
Garys 68 said:
You get new relays, new terminals to crimp on istead of splicing decades old wires, and has a neat clear cover.
You might want to compare the prices of other manufacturers, Painles has a 3 gang on sale for $163.
http://painlessperformance.shptron.com/p/3-pack-relay-bank

mrvette said:
Garys 68 said:
If you need a multi relay panel, try the one below. Very good price and the terminals are very heavy duty.
http://www.haywireinc.com/index.cfm...ategory_id=-1/home_id=-1/mode=prod/prd167.htm
Click to expand...

:hissyfit: 50 bux, bad enough on the Spals...:crylol:

I just do a junkyard raid, for the motor home, I cut a mitsubitchy box and used about 2/3 of it for the relays controlling tons of crap...

:smash::hijack:
Click to expand...
Click to expand...

Gary, sorry, but been soldering wires for over 60 years now, yes since age 9 or so....wanna do electrical work, SOLDER your connections....IF the insulation is not baked out, and it wasn't in my '72 vette, that's FORTY YEARS now....you can easy scrape a mild corrosion and solder to the copper in a instant.....I honestly don't see buying hundreds of bux worth of harnesses that try to mimic the stock shit, ESPECIALLY when it needs mods for what/where I want to go with it.....


:flash:
 
I have the trinary switch. Picked up the relays today from my buddy at the stereo shop. Spent an hour or so jogging Bullsharks memory today on how to wire them up. $25 bucks for 2 relays and connectors. Will solder and shrink wrap tomorrow. VA had a schematic for the trinary.
I also asked the question on Holleys forum and here is their answer.
The Holley HP ECU does have two programmable "PWM+" & "PWM−" Outputs (or two 12V & ground switched Outputs and four Inputs).
However, all these Outputs are limited to 2 amps, so an appropriate electronic (PWM) relay is necessary.

First, you'll need to create the custom Output(s) in the I/O ICF. Name it, select PWM+ or PWM−, Enable & Configure it.
You'll need to program which two ECU parameters (X & Y axis) you'd like to control the PWM Output (in Outputs - PWM Setup).
Then "Pin Map" this new Output to an available J1 pin/connector (see "View Outputs"), and run this wire to the PWM relay.

FYI: Holley's 554-111 High Current Relay (device/solenoid driver) is not for use as a continuous duty pulsing relay.
It's rated at 40 amps and can operate at 100% duty cycle continuously or temporarily pulsing (PWM) high currents.

The HP ECU only has four Inputs and four Outputs.
You most likely won't want to use two of them for a PWM fan controller.
You'll probably find more important things to control with the ECU.
The ECU already has two existing electric fan Outputs in Basic I/O (System Parameters).
 
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Hey Don, just read your post here. Hold the phone. We don't want to run the fans with a PWM output. Need to use the ground switched discrete I/O with Bosh relay's and fuses. Talk to you tomorrow.
 
mrvette
"over 60 years now, yes since age 9"
you win, that tells me I'm not going to change your mind ;-)

donnie
Not sure of the requirements for the pwm. Simple on/off thermostat control sounds simpler. Thinking I agree with bullshark.
I would reccomend wiring for a ground controlling the relays. Most, if nat all, thermostatic switches and trinary switches are set up for that.
 
Picked up a dual fan from a Z28 $75 from junk yard. Fit was very nice with a few holes drilled and a couple of tabs modified. Mounted a couple of relays and will use the Holley ECU to controls the on/off. Thanks to BullShark for the lesson on relays.
 
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I powered my electric fans on my 68..BeCool radiator and fans, directly from the alternator. I don't think they should be powered from the battery. If you power them from the battery, you'll see a constant charge current on the ammeter. The ammeter will show the running power for the fans.

All electrical loads should, my opinion, be powered from the alternator. Let's say you're driving on a hot, rainy summer night in Florida and you've got the radio blasting, the AC is on, the headlights are on, the electric fans are on, the windshield wipers are flopping. With a proper electrical system, you ammeter will be reading 0. If everything is correct, the alternator will be powering everything. The ammeter is designed only to show charge/discharge status of the battery. If you connect loads to the battery itself, you will ruin the integrity of the ammeter's reporting of the battery status. You want the ammeter to only show if the BATTERY is charging or discharging. You don't want to add other electrical power loads that disguise the battery's charge/discharge status. My opinion.
 
Garys 68 said:
You get new relays, new terminals to crimp on istead of splicing decades old wires, and has a neat clear cover.
You might want to compare the prices of other manufacturers, Painles has a 3 gang on sale for $163.
http://painlessperformance.shptron.com/p/3-pack-relay-bank
Click to expand...

Way, way too much.
Try Allied Electronics for that stuff.
50 amp continuous 5 pin Bosch style relays starting at $1.50 with or without resistor, gangable relay sockets (same as Painless), manual reset breakers etc.
Faster shipping too. Most expensive part is the wiring.

Good to solder and shrink everything.
 
68/70Vette said:
I powered my electric fans on my 68..BeCool radiator and fans, directly from the alternator. I don't think they should be powered from the battery. If you power them from the battery, you'll see a constant charge current on the ammeter. The ammeter will show the running power for the fans.

All electrical loads should, my opinion, be powered from the alternator. Let's say you're driving on a hot, rainy summer night in Florida and you've got the radio blasting, the AC is on, the headlights are on, the electric fans are on, the windshield wipers are flopping. With a proper electrical system, you ammeter will be reading 0. If everything is correct, the alternator will be powering everything. The ammeter is designed only to show charge/discharge status of the battery. If you connect loads to the battery itself, you will ruin the integrity of the ammeter's reporting of the battery status. You want the ammeter to only show if the BATTERY is charging or discharging. You don't want to add other electrical power loads that disguise the battery's charge/discharge status. My opinion.
Click to expand...

010752 said:
Garys 68 said:
You get new relays, new terminals to crimp on istead of splicing decades old wires, and has a neat clear cover.
You might want to compare the prices of other manufacturers, Painles has a 3 gang on sale for $163.
http://painlessperformance.shptron.com/p/3-pack-relay-bank
Click to expand...

Way, way too much.
Try Allied Electronics for that stuff.
50 amp continuous 5 pin Bosch style relays starting at $1.50 with or without resistor, gangable relay sockets (same as Painless), manual reset breakers etc.
Faster shipping too. Most expensive part is the wiring.

Good to solder and shrink everything.
Click to expand...

Allied radio....Been a while, surprised they still around.....and yes, all heavy loads come off the alt out stud directly, I not too concerned about the amp meter, as I use a voltmeter, but would be concerned about the battery charge rate as it would never ever see 14.8 volts if the fans are on, and in a daily use/city stop go shituation you can run the battery pretty lo....:smash:
 
Oh I agree, $163 is way too much. That's why I went for the 4 gang Haywire setup for $46. It's also a single unit with cover, not the kind you slip together (Painless). It also has a raised base allowing for flat mounting which worked perfect for me.

010752 said:
Garys 68 said:
You get new relays, new terminals to crimp on istead of splicing decades old wires, and has a neat clear cover.
You might want to compare the prices of other manufacturers, Painles has a 3 gang on sale for $163.
http://painlessperformance.shptron.com/p/3-pack-relay-bank
Click to expand...

Way, way too much.
Try Allied Electronics for that stuff.
50 amp continuous 5 pin Bosch style relays starting at $1.50 with or without resistor, gangable relay sockets (same as Painless), manual reset breakers etc.
Faster shipping too. Most expensive part is the wiring.

Good to solder and shrink everything.
Click to expand...
 
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