relay install

JNasty

i drive fast cars (supra)
Jun 25, 2005
358
0
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41
Jacksonville fl
i dont really know alot about wiring but i do like to learn and do things myself so i though i would ask you guys and i have researched the crap out if this and learned alittle about it but not where and how to hook it all up...

so. im running dual cooling fans and i have a relay made by beuler. its a (bu-5083-0000) same basic layout as figura 1 in this web page http://www.the12volt.com/relays/relays.asp i know how it works but need to know how to hook it to my fans. my relay has a harness with it and ill tell you what wire colors go where on the relay.. the relay i have is set up to come on at 200 and shut off at 185 i think , it was on my old car and i just cant remember how to install it back on the car.
so here goes and ill tell you where i think they go so tell me if im wrong

87= 1 orange (fused) and 1 blue wire (not fused) (i think orange is the power out to the fans and blue not used)
86= black ( ground)
87a= ( not used)
30=red (power from battery)
85= 1 green and 1 brown wire (i think that they connect to the temp switch in the radiator green on one side and the brown on the other side of the temp switch)

also any help on how to test a relay with a multimeter would be great..
 

metaphysico

Mad Scientist
Jan 2, 2008
428
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Gainesville, Georgia
30 is power in from the battery or key on power to the relay should be fused close to the battery.
87 is power out to the load ie your fans, so that wire goes from relay to your fans.
86 ground hook straight to ground.
85 trigger, this is a power wire but it will only be power under certain instances the reason you have two is that one is going to your temp switch and one is probably going to the ac fan control. its a blue and black pair of wires in a black connector near the bottom of the battery/ fuse panel area.

Now the last thing you need is power for your temp switch. A temp switch is like a relay where it connects two pins but it does it when it gets hot enough. So you will need a key on power wire (only has power when the key is on), fused(put the fuse close to battery), going to your temp switch then the other wire on the switch will hook to 85 on the relay. Also find the power wire from the ac fan circuit should be the blue wire but not sure and hook it to the other wire connected to 85.

85 and 86 are interchangeable as long as one side has power and the other side has ground the relay will "turn on" passing power through from 30 to 87. To test the relay put power on one of these 85 or 86 and put ground on the other. then with a multimeter do a resistance test on the relay. Should have low resistance ie less than .8ohm. When the power and ground are hooked up you should hear an audible click.

I will return and make a wiring diagram for you, bored as hell at work.
 

JNasty

i drive fast cars (supra)
Jun 25, 2005
358
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41
Jacksonville fl
ok thanks. is there anywhere that i can hook up the power supply instead of the battery itself bacause do to my ffim the battery is in the trunk.. also my ac is not in the car so i should have some live wires there i could possibly use if i can and need be
 

metaphysico

Mad Scientist
Jan 2, 2008
428
0
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44
Gainesville, Georgia
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---------- Post added at 11:34 AM ---------- Previous post was at 11:30 AM ----------

If you have no ac you dont have to worry about the second wire on relay terminal 85. Tap into where ever you tapped the line that goes to your starter main power. The large wire off the starter hooks to the battery, you should have a wire for that accessible somewhere. Or tie off from the large wire on the alternator it is direct to the battery too. Just make sure to fuse your wire close to the tie in point.
 

JNasty

i drive fast cars (supra)
Jun 25, 2005
358
0
0
41
Jacksonville fl
yeah ill wire it strait to the alt..so red will go to the alt, black ground,, orange to the fan motor,brown to the temp switch,the blue is not needed or i can run it to the other fan as 1 hot to each individual fan instead of 1 hot for both fans together, and the green will go?also the green wire has a resistor in it or something but from one side of that resistor to the other measures 1.0 to 1.2 ohms...
 
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JNasty

i drive fast cars (supra)
Jun 25, 2005
358
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0
41
Jacksonville fl
got them all figures out except do i run the brown(wo/resistor) or green (w/resistor)to the temp switch and what should i do with the other one. also what size fuses would you suggest putting for the relay and for the temp switch?
 

metaphysico

Mad Scientist
Jan 2, 2008
428
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44
Gainesville, Georgia
Well that depends on what temp switch you are running if your running an aftermarket adjustable temp switch you will not need a relay if you are trying to run off the stock temp switch or one that is aftermarket but not adjustable it may have the resistor to make the relay come on later. Which setup are you running for temp switch?
 

JNasty

i drive fast cars (supra)
Jun 25, 2005
358
0
0
41
Jacksonville fl
to be honest i cant remember i think ill just bypass that and wire the relay to come on when the car is switched on i guess, so there for red will go to a ignition + black to ground, and orange to the fans right? or would it go orange to power and red to fans?
 

metaphysico

Mad Scientist
Jan 2, 2008
428
0
0
44
Gainesville, Georgia
You dont want them running all the time, and I overlooked the temp switch being in the radiator so its an aftermarket unit. Just hook to that unit, the resistor was probably put on there to make them come on a little later, but if they come on early its not a big deal compared to having them come on with key on power. Try the brown on the temp switch and if they are coming on too early then try the other one with the resistor and see when they come on then.
 

JNasty

i drive fast cars (supra)
Jun 25, 2005
358
0
0
41
Jacksonville fl
yeah its a temp switch in the radiator thats what ill do is the try the brown and see what happens cause its the one that still has the little harness that would hook to the switch..but my fuel lines are still undone so cant try it for a while.. thanks for your help bro!