Need to wire up an electric fan on my 360...

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sazzlefrats

sazzlefrats

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Important Facts:
1. I'm clueless
2. I have a 1974 360 with 4spd, no AC.
3. The bare minimum of wires are hooked up to run the vehicle... nothing else. Many wires are probably completely missing and so is a lot of the standard equipment.
4. I feel I may have to buy something to make this work, but I'm not sure what. Its not a show car, but I don't want to make it look worse than it already is. I don't have a rats nest of wiring and would like to keep it that way.
5. :violent1: help?


I have an electric fan installed on my radiator, but.... omg there is electrical work to be done. Here's the instructions from the outfit that I bought all this from...

"you can use a standard automotive relay from most auto parts stores. The coil or control circuit of the relay should be connected to a key-on 12 volt source so the fan will not run after the key is turned off. You will use 4 terminals of the relay. Terminal 30 will be wired to a 25 or 30 amp fuse from the battery, starter solenoid, or horn relay 12 volt distribution point. Terminal 87 will go to the fan. Terminal 85 will go to the key-on 12 volt source. Terminal 86 will be wired to the coolent temp switch in the manifold. Here is a diagram. Disregard the wire colors.
[FONT=arial, sans-serif]If you have A/C, you can wire a trinary switch to turn the fan on when the condensor needs more airflow. If you don't have a trinary switch in the A/C system, you can use another relay to control the fan relay from the compressor clutch circuit.[/FONT]"


The diagram is fun unfortunately I couldn't copy it inside the instant message I received.


From the diagram, it looks simple enough, just I don't know what all the parts are.


From the battery I need a positive red wire going to a 30amp fuse which goes to.... a relay? This relay has a yellow wire going to a sending unit (I'm guessing thats the heater sending unit on top of the intake manifold. And there's an orange wire going to the ignition. So is this relay already on my car? Where do I find the orange wire? And I'm pretty sure I have no wire on my sending unit right now, (my gauges do not work). And then there's another red wire comming off the relay which goes to the fan (the fan BTW has two black wires, I'm guessing this means the fan doesn't care which way it gets voltage, but I'm also guessing that if I choose the wrong one my fan is going to spin backwards).


And then in the diagram there are instructions for a override switch... Why would I want this?
 
Sounds like you don't have "all this stuff."

You need to buy a good heavy inline fuse holder, preferably with no 12 or 10 gauge wire

If you have the Mopar starter relay, the battery stud on the Mopar relay makes a good place to take off from. The Mopar relay looks like this:

starterrelay.jpg


You cannot use your Mopar temp sender which is for a gauge. You need a temp sender SWITCH designed for a fan. These come in several designs, some screw into the intake manifold just like your gauge sender, some have a sensor tube that clamps onto the bottom of the top hose, and some are adjustable

The relay they are referring to is known as a "Bosch relay" and is a common, standard, general purpose auto relay. Most parts stores have 'em, and you can buy a connector that fits the bottom

RAP_Relay.jpg


If you look at the bottom of a Bosch relay, the terminals are numbered: Some have 4, some have 5 terminals

relaybot.jpg


Just wire it like the destructions describe. The control coil of a Bosh relay is terminals 85 and 86. These do the same job as the two "push on" terminals of a Mopar start relay. That's the magnetic coil

The "normally open" contacts of a Bosch are terminals 30 and 87. These are the "switch"


So wire terminal 85 to the same place as your ignition power on/ off. This will power the relay, and when the fan thermostat ---which will connect to 86 turns on, the stat switch will ground term. 86, turning on the relay

The main power running the fan, the "switch" part of the relay, will be a big fuse coming from the battery (starter relay stud) to terminal 30. So this is hot all the time.

Then term. 87 goes off to the fan
 
I want my gauge to work and have the electric fan do its thing... and a switch will allow for that? Any idea which switch to buy?
 
BTW at idle, should my radiator and hoses get too hot to touch after about 10minutes without the fan running at all?
 
The gauge sender and the fan control switch are two separate components. Not practical to tie them into one sender."
 
sazzlefrats said:
BTW at idle, should my radiator and hoses get too hot to touch after about 10minutes without the fan running at all?
Click to expand...

Yes.

You can skip a temperature probe if you want to manually turn the fan on and off. Otherwise, follow the instructions so eloquently laid out by Mr. 67Dart273!!!
 
He could get a thermal relay controller and use it to run the fan but still have his temp guage.
My controller was about 50 bucks and I got it from Jegs, and it has the relay built in.

One wire to the starter relay or batt+ for power, and the other goes to the fan and you can set the on-off temp range.
This way he wouldn't have to wire up his own relay.
 
TrailBeast said:
He could get a thermal relay controller and use it to run the fan but still have his temp guage.
My controller was about 50 bucks and I got it from Jegs, and it has the relay built in.

One wire to the starter relay or batt+ for power, and the other goes to the fan and you can set the on-off temp range.
This way he wouldn't have to wire up his own relay.
Click to expand...

That sounds like what I want, do you think thats available at an O'reily or an Autozone?

What's the jegs part number?
 
It's available they usually keep them in the back. The brand is compressor works. They should have them. They are pre wired. There is on with its "own" adjustable temp controlling knob.

The kicker is getting past.the kid at the counter that tries to look it up in the computer. Look for the older gentleman and tell him you need an eletric fan controller. They come with instructions and pictures.

Something about pictures to go with the words just makes it make sense to me, I guess its my "dummy proof"

THEY ARE PRE WIRED!

Aj
 
I agree on getting a pre-wired fan-relay harness. I bought 3 approaches. An aux fan wiring kit for $15 on ebay. This was a factory recall kit for a GM SUV in AZ that dealers started unloading cheap, so bought 2. Just the relay and wiring harness, no temp sensor so I bought a temp switch separately on ebay (hard to find a <200 F one). Then I saw a Hayden 3651 kit on rockauto for $25. This is the better model w/ screw-in temp sensor and adjustable setpoint that you see for $50+, sometimes relabelled Jegs or Summit. Before above, I bought the solid-state relay used on my 2002 T&C minivan ($29) since it drives 2 fans and should last longer, but more work to wire, so will probably just keep as a spare.

The fan circuits can run stand-alone quite easy. They run the control thru the engine computer in most modern cars, but mainly just to monitor failures. I saved some info on wiring it so the fan also comes on w/ the AC compressor. As I recall, that requires another relay (can be small since just for logic). If you install an engine controller like a Holley Commander 950, many can control the fan.
 
Hey does this look right? Grounded to the body, positive to hayden 3653 controller, to 30amp relay to battery... done.

Pros: No messing around with the ignition, and I'm free to hook up my regular temperature sending unit to my dash.

Cons: ignition switch is bypassed... fans could run with engine off.

 
Looks good.
Now all you have to do is decide if you want it fully automatic or not.
Full auto you power it reight from the battery, and if you want it to go off when the key is off then connect it to an ignition power source.

sazzlefrats said:
Hey does this look right? Grounded to the body, positive to hayden 3653 controller, to 30amp relay to battery... done.

Pros: No messing around with the ignition, and I'm free to hook up my regular temperature sending unit to my dash.

Cons: ignition switch is bypassed... fans could run with engine off.

Click to expand...
 
I found what I think is the voltage regulator. It has three hookups, the lower one has constant power, and the other two... I have no idea, the voltmeter didn't show any power, so I figure one is ignition? I didn't start up the engine, maybe I should have. Anyhow I hooked the positive wire for the fan to that instead of the battery.

I think I'm probably okay with full power all the time, where should I find the ignition wire to tap into?

And I learned something disappointing.. the side of the motor says 318, guess the previous owner lied to me or didn't know it wasn't a 360 :-(
 
sazzlefrats said:
I found what I think is the voltage regulator. It has three hookups, the lower one has constant power, and the other two... I have no idea, the voltmeter didn't show any power, so I figure one is ignition? I didn't start up the engine, maybe I should have. Anyhow I hooked the positive wire for the fan to that instead of the battery.

I think I'm probably okay with full power all the time, where should I find the ignition wire to tap into?

And I learned something disappointing.. the side of the motor says 318, guess the previous owner lied to me or didn't know it wasn't a 360 :-(
Click to expand...
wow thats messed up.well the teener runs good right?
 
bad440 said:
wow thats messed up.well the teener runs good right?
Click to expand...

Yeah its annoying to get the shaft like that, but a 318 and a 360 share the same block don't they, if so a new crank and rods and I got a 360!? All the same it seems to run fine. Starts up and idles well. I haven't done anything more than drive it around the block once.
 
sazzlefrats said:
Yeah its annoying to get the shaft like that, but a 318 and a 360 share the same block don't they, if so a new crank and rods and I got a 360!? All the same it seems to run fine. Starts up and idles well. I haven't done anything more than drive it around the block once.
Click to expand...

They are not the same 318/360 so crank and rods won't do it.

If your fan controller has thermostatic control (turns itself on and off depending on temp) you can connect it right at the relay on the heavy positive terminal.
 
damn boy, dont be disappointed about your 318. I'll take it if ya dont want it.....
 
TrailBeast said:
They are not the same 318/360 so crank and rods won't do it.

If your fan controller has thermostatic control (turns itself on and off depending on temp) you can connect it right at the relay on the heavy positive terminal.
Click to expand...

Exactly what I beleive I did. Done... I'll fire it up next weekend and let it idle until the fan turns on.

Projects left
-Power Steering Leak (looks like at the hoses connected to the pump)
-Real dual exhaust (instead of my mock up)
-Master Brake Cylinder Leak (installed remanufactured one)
-Oil Change
-Connect Dart and Power Wagon turn signals/brake lights, horns, and anything else that might not be working electrical work.
-Full Interior Restore
-Exterior strip and into black primer, put all chrome on the car.
-Drive it!
 
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