Electric Fan Relay - The 1947 - Present Chevrolet & GMC Truck Message Board Network

CJJ67 · 11-29-2007, 05:10 PM

I posted this question before but I still haven't gotten an answer. I'm trying to put an electric fan in my truck but I am stuck trying to correctly hook up the relay switch. I bought the grand jeep fan from the dealer and I have, what I think, is a electric fuel pump relay kit (given to me by my neighbor) from keep it clean. My question is, can I use this relay kit to hook up my electric fan. The kit is a 12V 30/40A relay, 16awg wiring, 30A circuit breaker and I purchased a thermal sensor for the 350 engine head. If I can use it, my relay numbers are 87, 86, 85 and 30. What number goes where to make this fan work. Oh yeah, my baby is a 67 stepside, short bed 350 Chevy. Thanks for any help that you can give me.

Andy4639 · 11-29-2007, 05:18 PM

This should help you. Anything can be hooked up to the relay it doesn't care what it is.

70GMCer · 11-29-2007, 07:03 PM

Here's a copy of the instructions from the kit that I will be using for my Jeep fan install......

steve

71Rat · 11-29-2007, 09:34 PM

what you guys are failing to remember is the thermo switch provides the ground for the switched side of the relay. according to everyones wiring diagram there is no need for that thermo switch as you will control the fan with a manual switch from your ignition (the positive side).

If you want to use a thermo switch then eliminate the switch on the positive side (on pin 86). run a constant hot (positive) to pin 86. Then on the ground side (pin 85) provide the thermo switch. then when the engine gets to the temp. your thermo switch is rated for it will provide the ground and kick on your fan.

I hope this helps you guys out, any questions ask away

71Rat · 11-29-2007, 09:37 PM

also a side note, if you dont want your fan to run after you shut off the truck run the power to pin 86 through your ignition switch.

hope this all helps and i didnt go over anyones head,
71rat

CJJ67 · 11-29-2007, 11:58 PM

Thank you all for your help and input. This is why my truck is my therapy and not drugs. You guys are absolutely great. Many thanks for your help. I will put it together when I get home tomorrow.

71Rat, thanks for posting your electric fan install that got me started on this in the first place.

Andy4639 · 11-30-2007, 12:02 AM

Quote:

71Rat
what you guys are failing to remember is the thermo switch provides the ground for the switched side of the relay. according to everyones wiring diagram there is no need for that thermo switch as you will control the fan with a manual switch from your ignition (the positive side).

I'm not failing to remember anything...The drawing is generic. Like I said the relay doesn't care where it grounds or get's 12 volts from.
All I was doing is showing a basic drawing. You hook it up as you want per you use.

71Rat · 11-30-2007, 06:16 AM

CJJ67: Im glad I could help out

Andy4639: I didnt mean to offend you! if anything thank you for providing the drawings to give a rough idea of how a relay works.

Andy4639 · 11-30-2007, 03:21 PM

That's cool. No offense taken.
I was just showing what connections went where on the relay.

piecesparts · 11-30-2007, 06:28 PM

There is always the deal that if you run your fan on a manual switch, then the day will come that you will EITHER forget to turn it on or you will get bummed by the fact that you ALWAYS have to turn it off.

I put my fans on a switched circuit from my ignition (feeding to the relay) and the ground circuit is fed by the temp switch in the block for the turn on point. This allows the vehicle to warm up easily and then turn the fan on when I actually need it NOT when I happen to think about it or maybe to late. If you choose to have A/C, then there is that factor to deal with also. On a later model truck, you can even tie into the motor's temp switch for the computer feed.

Look at this website for a wiring diagram that is really complete. http://www.spalusa.com/fans/automate...85FH-195FH.pdf

Andy4639 · 11-30-2007, 07:03 PM

I have a electric and the motor fan on the 71. The electric is hooked to the A/C fan switch so when I turn the A/C on the electric fan kicks on by the relay.

CJJ67 · 12-07-2007, 12:34 AM

I got a couple more questions left. Do I run pin 30 to the constant hot through the circuit breaker that pin 86 is connected to? I am just about there but my fan never came on and I drove for almost 40 minutes today. I'll check tomorrow to see if I even have a thermastat in the intake. One thing for sure though, the fan looks like it was made for these trucks. Oh yeah, I haven't taken the flex fan off because I wasn't sure if I had hooked up the electric fan correctly. Looks like I didn't.

Andy4639 · 12-07-2007, 03:35 AM

Look at my 2nd drawing. No you don't connect them together.
Have you got the fan grounded. The fan has to be grounded and the relay, they will be seperate grounds.

petey-pablo · 12-11-2008, 07:00 PM

Sorry to jack this thread but I posted this elsewear with no luck and since you guys are on the same topic please I can use the help I would like something to do this weekend...Can any one help me with a diagram on how to wire Dual Electric fans useing 2 relays in the best posable way I heard tHAT IN SERIES would work best But I have searched online and I haven't found anything I also want to put a toggle switch so I can bypass the temp sensor if I wanted to turn it on early if needed But keep it hot Ignition only"just in case I forget to turn it off". This is what I have to work with thanks... I have RELAYS WITH WIRE Harness wire colors as follows RELAY #86 Black wire #87 Yellow Wire #87a Red wire #85 White Wire and #30 Blue Wire.. My fans Harness Are Fan #1 White & Black Wires Fan#2 Blue & Black Wires and I also have a Temp Sensor with a Black and Red wire on my Radiator, I just need to buy my toggle swich..I also have a Have Fuse Block Under the hood with 7 Circuits 3-constant hot and 4 ignition hot circuits From Cirkit Boss Aux Form Painless. I Have NO A/C So I don't need the diode I read about I hope.......Any help would be greatly apreciated thanks & sorry once again for Jacking your thread.........
Pablo

piecesparts · 12-11-2008, 09:52 PM

Go to the SPAL website and open up the acessories section for the FANS and find the Fan PWM item. The attached page in the blue letters for the fan has some pictures of wiring diagrams for different fan setups. See attached web info and look for the diagrams inside the PDF file.

http://www.spalusa.com/fans/automate...PWM-V3_ins.pdf

ERASER5 · 12-12-2008, 12:41 AM

O'Rilleys has a fan controller for about $40. Add a fuse to a keyed power source and follow the instructions.

SPAL has better options, but are WAY more expensive.

72BLUZ · 12-12-2008, 12:44 AM

those schematics are self explanatory

**VetteVet** · 12-12-2008, 01:37 AM

Quote:

Originally Posted by 71Rat

what you guys are failing to remember is the thermo switch provides the ground for the switched side of the relay. according to everyones wiring diagram there is no need for that thermo switch as you will control the fan with a manual switch from your ignition (the positive side).

If you want to use a thermo switch then eliminate the switch on the positive side (on pin 86). run a constant hot (positive) to pin 86. Then on the ground side (pin 85) provide the thermo switch. then when the engine gets to the temp. your thermo switch is rated for it will provide the ground and kick on your fan.

I hope this helps you guys out, any questions ask away

Take another look at the diagram in post three and you will see that the thermal switch also runs the AC clutch. If you wired 86 hot from the key
you couldn't have the AC clutch wire in or it would run all the time.

Keep in mind that the thermal switch is just a switch that is activated by temperature and will provide continuity whenever the coolant temperature gets to a preset level. It doesn't care if it's switching a hot circuit or a ground circuit. IOW it will work on 85 or 86.

70GMCer · 12-12-2008, 08:59 AM

Yes, that thermo switch is normally opened until the temp rises. Since using the diagram I posted, Mine works great. No problems. It also is wired for manual use in case the thermo switch fails.

**VetteVet** · 12-12-2008, 09:37 AM

For the record, I did a little research and the thermal switches also come in a grounded
body type. Where the body of the switch completes the ground circuit, as in a temperature sending unit. Obviously this type would not work for a hot side wiring circuit and would have to be used on the relay grounding terminal. I had thought of that in my prior post but I was focused on the OP's wiring diagrams.
The important thing to remember is to know what type thermal switch is in the kit and to follow the directions in the kit.
I'm glad yours works great and here is a diagram of one that I believe is like yours.

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Name: hppp_0801_26_z+improved_pontiac_cooling_system+diagram.jpg
Views: 4431
Size: 37.1 KB

11-29-2007, 09:34 PM	#4
71Rat ran out of money Join Date: Apr 2003 Location: northern, NJ Posts: 925	Re: Electric Fan Relay what you guys are failing to remember is the thermo switch provides the ground for the switched side of the relay. according to everyones wiring diagram there is no need for that thermo switch as you will control the fan with a manual switch from your ignition (the positive side). If you want to use a thermo switch then eliminate the switch on the positive side (on pin 86). run a constant hot (positive) to pin 86. Then on the ground side (pin 85) provide the thermo switch. then when the engine gets to the temp. your thermo switch is rated for it will provide the ground and kick on your fan. I hope this helps you guys out, any questions ask away __________________ Modify everything, leave nothing alone!~

11-29-2007, 09:37 PM	#5
71Rat ran out of money Join Date: Apr 2003 Location: northern, NJ Posts: 925	Re: Electric Fan Relay also a side note, if you dont want your fan to run after you shut off the truck run the power to pin 86 through your ignition switch. hope this all helps and i didnt go over anyones head, 71rat __________________ Modify everything, leave nothing alone!~

11-29-2007, 11:58 PM	#6
CJJ67 Registered User Join Date: Sep 2003 Location: Temecula, Ca. Posts: 64	Re: Electric Fan Relay Thank you all for your help and input. This is why my truck is my therapy and not drugs. You guys are absolutely great. Many thanks for your help. I will put it together when I get home tomorrow. 71Rat, thanks for posting your electric fan install that got me started on this in the first place.

11-30-2007, 03:21 PM	#9
Andy4639 Old member Join Date: Jan 2002 Location: Liberty, & Garden City S.C. , U.S. Posts: 19,936	Re: Electric Fan Relay That's cool. No offense taken. I was just showing what connections went where on the relay. __________________ 1971 LWB Custom, 6.0LS & 4L80E, Speedhut.com GPS speedometer & gauges with A/C. 20" Boss 338's Grey wheels 4 wheel disc brakes. My Driver Seeing the USA in a 71 Upstate SC GM Truck Club 2013,14 and 2016 Hot Rod Pour Tour http://upstategmtrucks.com/ Get out and drive the truck this summer and have some fun! It sucks not being able to hear! LWB trucks rule, if you don't think so measure your SWB! After talking to tech support at Air Lift I have found out that the kit I need is 60811. Per the measurements I gave them. Ride height of truck inside spring and inside diameter of springs.

11-30-2007, 06:28 PM	#10
piecesparts Parts and more parts Join Date: Nov 2003 Location: Lebo, Kansas (middle of nowhere Posts: 6,821	Re: Electric Fan Relay There is always the deal that if you run your fan on a manual switch, then the day will come that you will EITHER forget to turn it on or you will get bummed by the fact that you ALWAYS have to turn it off. I put my fans on a switched circuit from my ignition (feeding to the relay) and the ground circuit is fed by the temp switch in the block for the turn on point. This allows the vehicle to warm up easily and then turn the fan on when I actually need it NOT when I happen to think about it or maybe to late. If you choose to have A/C, then there is that factor to deal with also. On a later model truck, you can even tie into the motor's temp switch for the computer feed. Look at this website for a wiring diagram that is really complete. http://www.spalusa.com/fans/automate...85FH-195FH.pdf

11-29-2007, 05:10 PM	#1
CJJ67 Registered User Join Date: Sep 2003 Location: Temecula, Ca. Posts: 64	Electric Fan Relay I posted this question before but I still haven't gotten an answer. I'm trying to put an electric fan in my truck but I am stuck trying to correctly hook up the relay switch. I bought the grand jeep fan from the dealer and I have, what I think, is a electric fuel pump relay kit (given to me by my neighbor) from keep it clean. My question is, can I use this relay kit to hook up my electric fan. The kit is a 12V 30/40A relay, 16awg wiring, 30A circuit breaker and I purchased a thermal sensor for the 350 engine head. If I can use it, my relay numbers are 87, 86, 85 and 30. What number goes where to make this fan work. Oh yeah, my baby is a 67 stepside, short bed 350 Chevy. Thanks for any help that you can give me.

11-29-2007, 05:18 PM	#2
Andy4639 Old member Join Date: Jan 2002 Location: Liberty, & Garden City S.C. , U.S. Posts: 19,936	Re: Electric Fan Relay This should help you. Anything can be hooked up to the relay it doesn't care what it is. __________________ 1971 LWB Custom, 6.0LS & 4L80E, Speedhut.com GPS speedometer & gauges with A/C. 20" Boss 338's Grey wheels 4 wheel disc brakes. My Driver Seeing the USA in a 71 Upstate SC GM Truck Club 2013,14 and 2016 Hot Rod Pour Tour http://upstategmtrucks.com/ Get out and drive the truck this summer and have some fun! It sucks not being able to hear! LWB trucks rule, if you don't think so measure your SWB! After talking to tech support at Air Lift I have found out that the kit I need is 60811. Per the measurements I gave them. Ride height of truck inside spring and inside diameter of springs.

11-29-2007, 07:03 PM	#3
70GMCer Senior Member Join Date: Apr 2005 Location: Joppa, Maryland Posts: 4,408	Re: Electric Fan Relay Here's a copy of the instructions from the kit that I will be using for my Jeep fan install...... steve Attached Images __________________ 1997 GMC Sierra Ext 1965 Mustang

11-30-2007, 06:16 AM	#8
71Rat ran out of money Join Date: Apr 2003 Location: northern, NJ Posts: 925	Re: Electric Fan Relay CJJ67: Im glad I could help out Andy4639: I didnt mean to offend you! if anything thank you for providing the drawings to give a rough idea of how a relay works. __________________ Modify everything, leave nothing alone!~

11-30-2007, 07:03 PM	#11
Andy4639 Old member Join Date: Jan 2002 Location: Liberty, & Garden City S.C. , U.S. Posts: 19,936	Re: Electric Fan Relay I have a electric and the motor fan on the 71. The electric is hooked to the A/C fan switch so when I turn the A/C on the electric fan kicks on by the relay. __________________ 1971 LWB Custom, 6.0LS & 4L80E, Speedhut.com GPS speedometer & gauges with A/C. 20" Boss 338's Grey wheels 4 wheel disc brakes. My Driver Seeing the USA in a 71 Upstate SC GM Truck Club 2013,14 and 2016 Hot Rod Pour Tour http://upstategmtrucks.com/ Get out and drive the truck this summer and have some fun! It sucks not being able to hear! LWB trucks rule, if you don't think so measure your SWB! After talking to tech support at Air Lift I have found out that the kit I need is 60811. Per the measurements I gave them. Ride height of truck inside spring and inside diameter of springs.

12-07-2007, 12:34 AM	#12
CJJ67 Registered User Join Date: Sep 2003 Location: Temecula, Ca. Posts: 64	Re: Electric Fan Relay I got a couple more questions left. Do I run pin 30 to the constant hot through the circuit breaker that pin 86 is connected to? I am just about there but my fan never came on and I drove for almost 40 minutes today. I'll check tomorrow to see if I even have a thermastat in the intake. One thing for sure though, the fan looks like it was made for these trucks. Oh yeah, I haven't taken the flex fan off because I wasn't sure if I had hooked up the electric fan correctly. Looks like I didn't.

12-07-2007, 03:35 AM	#13
Andy4639 Old member Join Date: Jan 2002 Location: Liberty, & Garden City S.C. , U.S. Posts: 19,936	Re: Electric Fan Relay Look at my 2nd drawing. No you don't connect them together. Have you got the fan grounded. The fan has to be grounded and the relay, they will be seperate grounds. __________________ 1971 LWB Custom, 6.0LS & 4L80E, Speedhut.com GPS speedometer & gauges with A/C. 20" Boss 338's Grey wheels 4 wheel disc brakes. My Driver Seeing the USA in a 71 Upstate SC GM Truck Club 2013,14 and 2016 Hot Rod Pour Tour http://upstategmtrucks.com/ Get out and drive the truck this summer and have some fun! It sucks not being able to hear! LWB trucks rule, if you don't think so measure your SWB! After talking to tech support at Air Lift I have found out that the kit I need is 60811. Per the measurements I gave them. Ride height of truck inside spring and inside diameter of springs.

12-11-2008, 07:00 PM	#14
petey-pablo "THE GREEN GOBLIN" Join Date: Mar 2008 Location: Fremont Ca. Posts: 1,025	Re: Electric Fan Relay Sorry to jack this thread but I posted this elsewear with no luck and since you guys are on the same topic please I can use the help I would like something to do this weekend...Can any one help me with a diagram on how to wire Dual Electric fans useing 2 relays in the best posable way I heard tHAT IN SERIES would work best But I have searched online and I haven't found anything I also want to put a toggle switch so I can bypass the temp sensor if I wanted to turn it on early if needed But keep it hot Ignition only"just in case I forget to turn it off". This is what I have to work with thanks... I have RELAYS WITH WIRE Harness wire colors as follows RELAY #86 Black wire #87 Yellow Wire #87a Red wire #85 White Wire and #30 Blue Wire.. My fans Harness Are Fan #1 White & Black Wires Fan#2 Blue & Black Wires and I also have a Temp Sensor with a Black and Red wire on my Radiator, I just need to buy my toggle swich..I also have a Have Fuse Block Under the hood with 7 Circuits 3-constant hot and 4 ignition hot circuits From Cirkit Boss Aux Form Painless. I Have NO A/C So I don't need the diode I read about I hope.......Any help would be greatly apreciated thanks & sorry once again for Jacking your thread......... Pablo __________________ Petey-pablo "THE GREEN GOBLIN" 1972 Cheyenne 10 Short Fleet Side Front 2.5inch Spindles with 2inch Springs Rear 4inch drop Springs. 454BBC TH400,Posi 1971 Cheyenne 10 Long Fleet Side 454BBC TH350,Posi Sold Drive it like you stole it! Petey-pablo@sbcglobal.net

12-11-2008, 09:52 PM	#15
piecesparts Parts and more parts Join Date: Nov 2003 Location: Lebo, Kansas (middle of nowhere Posts: 6,821	Re: Electric Fan Relay Go to the SPAL website and open up the acessories section for the FANS and find the Fan PWM item. The attached page in the blue letters for the fan has some pictures of wiring diagrams for different fan setups. See attached web info and look for the diagrams inside the PDF file. http://www.spalusa.com/fans/automate...PWM-V3_ins.pdf

12-12-2008, 12:41 AM	#16
ERASER5 Registered User Join Date: Jun 2006 Location: Indiana Posts: 4,859	Re: Electric Fan Relay O'Rilleys has a fan controller for about $40. Add a fuse to a keyed power source and follow the instructions. SPAL has better options, but are WAY more expensive. __________________ '70 GMC C1500 LWB Power disc brakes. WooHoo! Posi 6 Lug Dana 60



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12-12-2008, 12:44 AM	#17
72BLUZ Registered User Join Date: Nov 2006 Location: lafayette, ga. Posts: 832	Re: Electric Fan Relay those schematics are self explanatory __________________ Freedom is never more than one generation away from extinction. We didn't pass it to our children in the bloodstream. It must be fought for, protected, and handed on for them to do the same.... Ronald Reagan

12-12-2008, 08:59 AM	#19
70GMCer Senior Member Join Date: Apr 2005 Location: Joppa, Maryland Posts: 4,408	Re: Electric Fan Relay Yes, that thermo switch is normally opened until the temp rises. Since using the diagram I posted, Mine works great. No problems. It also is wired for manual use in case the thermo switch fails. __________________ 1997 GMC Sierra Ext 1965 Mustang

12-12-2008, 09:37 AM	#20
VetteVet Msgt USAF Ret Join Date: Jan 2005 Location: Kalamazoo, Michigan Posts: 8,709	Re: Electric Fan Relay For the record, I did a little research and the thermal switches also come in a grounded body type. Where the body of the switch completes the ground circuit, as in a temperature sending unit. Obviously this type would not work for a hot side wiring circuit and would have to be used on the relay grounding terminal. I had thought of that in my prior post but I was focused on the OP's wiring diagrams. The important thing to remember is to know what type thermal switch is in the kit and to follow the directions in the kit. I'm glad yours works great and here is a diagram of one that I believe is like yours. __________________ VetteVet metallic green 67 stepside 74 corvette convertible 1965 Harley sportster 1995 Harley wide glide Growing old is hell, but it beats the alternative.

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