# Do I have an electrical problem?



## Baaad65 (Aug 29, 2019)

So out cruising last night about 80° outside car is running good, with the stereo on so my 100w amp and sub are on but not bumping, 16" puller fan running 15amp draw, and parking lights...I notice my volt meter is at 13v now I usually don't have the radio and parking lights on so ok getting into some stop and go traffic the temp gets up to 190-195° I flip on the two pusher fans @ 8amps each and the headlights voltage still at 13v but increases to 14v with more rpms ok...stop for a bite to eat pull the key out and it's warm (never had that happen) so I feel the ignition switch and it's warm maybe 85-90 ° idk. So I use my battery disconnect go eat for an hour drive home about 5-6 miles all the same things on except the pusher fans voltage is at about 14 get in the garage the key and switch are fine not warm at all. I'm running a 100amp Tuff Stuff 3 wire alternator and new regulator...do I have a problem, do I need a bigger alternator or is this a normal happening because I've never had it happen before and this is the third summer with all these components except the pusher fans were added this winter. Just don't want a fire while driving I hear that's a bad thing.


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## Baaad65 (Aug 29, 2019)

....I should add that I have a new engine harness and stock size battery cables but the original three alternator wires and I did laser temp the alternator after I got in the garage and it was between 140 and 165° depending where I pointed it but it always seems like you can't touch it after running for while but maybe some of that is engine heat, I did not feel the wires from it or the regulator.


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## GTO44 (Apr 11, 2016)

If you still have stock battery / charging wires than you need to upgrade. Stock alt was what 40amps? Short length of 10gauge took care of that. Now you have 100amps trying to run thru that same 10guage. You need to upgrade to at least a 4gauge (i prefer 2awg) for the alternator to battery and ground from battery to chassis.

Your ignition switch getting hot is a different thing. If you’re running the radio, amp, and electric fans off the stock fuse block then that extra draw is going thru the ignition switch. If it was rated for 40-50amps but now you pushing more current thru it than it will heat up. That’s why its always a good idea to use the ‘acc’ taps on the fuse block to trigger relays that are feeding direct battery power to the devices.

On another note, from my experience all pusher fans do is block incoming air. I would ditch those and get a better puller fan setup that will get the job done. We like to see at least 4,000 cfm from puller fans with a sealed shroud to cool properly. Its also handy to have a controller that can shut those electric fans off above lets say 50mph so the fans arent slowing down the incoming air at that speed.


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## Baaad65 (Aug 29, 2019)

Ok bare with me because electrical isn't my strong suit but I understand most things, you say upgrade the cable from the battery to the alternator but I only have a 4awg negative battery to engine, a 4awg positive directly to the starter then the 12awg? from the alternator into the loom which plugs into the fire wall block. So which one am I supposed to upgrade? And I do have my stereo and fans into the auxiliary terminals on the fuse block just never had this issue before but maybe I was running more than usual. As far as the fans I'm not running much of a shroud I know that's the problem but I don't like the looks of the bulky plastic shroud so I'm dealing with it for now, I have a 16" puller fan that's about 3000 cfms because the belt driven fan put to much drag on my serpentine belt and it would squeal, then I put two 13" pusher fans(1000cfms each) at the bottom of the radiator for when I get into traffic and it seems to be working well, stays at 200° on a 90° day in traffic







and they don't have much restriction as going down the road on a cooler day sometimes I don't have any of the fans on.


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## Baaad65 (Aug 29, 2019)

Ok so I searched some posts here about an alternator upgrade and all agree I need a bigger gauge wire to the battery, question is can I or do I have to leave the smaller wire going down to the starter connected or do I have to disconnect it?


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## LATECH (Jul 18, 2018)

#4 will be hard to work. Not to mention it is pure overkill

The real problem here is that the alternator large red wire runs through the ignition switch from the alternator then to the battery
It is NOT made to handle 60 + amps , at least not for long.

Run a #10 Ga AWG from the alternator straight to the battery . Then it will cool your switch down Ha Ha
seriously , I have checked this out on my 64 and the charge wire goes through the ignition switch then to the battery.That is the root of the problem

Leave the small wire and everything else intact


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## Baaad65 (Aug 29, 2019)

Ok, I could probably deal with a #6 or #8 pretty well unless that's still overkill? I didn't have any of the fans when I bought the alternator so now I'm thinking I should get a 140 amp because I forgot or didn't realize I'm not getting 100 amps at idle, so then with the 140 amp alternator I would probably need a 6 or 8 cable. I'm glad you said I could just add a wire because to replace the wire going to the starter would be a nightmare.


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## O52 (Jan 27, 2019)

I believe that changed in 65 LATECH. Alternator output to starter. Starter to battery. Red wire to ignition switch is spliced to the alternator-starter wire as part of the engine harness wiring. You can add a # 6 or 8 wire directly to the battery from the alternator but leave the original wire in place. You will then have two wires in parallel feeding the battery. 
In regards to the ignition switch getting hot have you added anything to the ignition circuit such as the aux panel you installed?


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## Baaad65 (Aug 29, 2019)

Haven't added anything since the two pusher fans last winter so been running all spring and summer like this, added it to the same auxiliary terminal the pusher fan was hooked to and all separately fused with one switch for the pushers one switch for the pullers. The small wire theory makes sense as you can't hook a garden hose to a fire hydrant and expect it to work, plus I probably never had that many things turned on at once....perfect storm. I guess I should try the bigger wire first before buying a bigger alternator unless there's a formula of adding up amperage loads of items to calculate what I need.


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## GTO44 (Apr 11, 2016)

LATECH said:


> #4 will be hard to work. Not to mention it is pure overkill
> 
> The real problem here is that the alternator large red wire runs through the ignition switch from the alternator then to the battery
> It is NOT made to handle 60 + amps , at least not for long.
> ...


Your’re saying NOT to upgrade to a 4awg for a high amp alt?? Ok ill make sure you never wire any of my cars LoL. Keep in mind i do this for a living.


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## LATECH (Jul 18, 2018)

GTO44 said:


> Your’re saying NOT to upgrade to a 4awg for a high amp alt?? Ok ill make sure you never wire any of my cars LoL. Keep in mind i do this for a living.


Kiss my A S S
If you are running 24 feet of wire then a 4 AWG would be needed
Get a grip

A 3 foot run of #10 is fine. It is not like the alternator is going to be used for welding,Even if you think it is too small...
the original wiring for the alternator is still present along with the added wire being discussed. And you want to add a 4 gauge ?
Remind me not to let you bill me for work done on my car 

I swear the more common sense I post the more BS i get from trolls and know it alls


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## LATECH (Jul 18, 2018)

O52 said:


> I believe that changed in 65 LATECH.


Pretty sure it changed in 66
Unless you have a wiring diagram we can look over. That would be awesome

OP said his alternator lead goes into the harness and goes to the bulkhead connector.
Sounds like 64-65 is the same


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## GTO44 (Apr 11, 2016)

Op im done. If you want real advice PM me. There is no circumstance inwhich a 10awg wire is acceptable for 100amp alternator.

To LAtech, im wrapping up a 200k restomod chevelle for an NBA player and the shop is completely full of high end wiring jobs. Do you boo. Wire your cars however you want. When you start giving BS advice to random people is where i have a problem.


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## Baaad65 (Aug 29, 2019)

Whoa guys, didn't want to start a pissing contest but LA has a point the longer the run the more resistance = heat and loss of signal, I'm only talking about a 16" wire plus like stated I still have the original wire I believe looks and feels like a 12# based on me wiring enough 110-240v commercial stuff. So what's everyone's opinion on upgrading to a 140 amp alternator without starting another war? Aslo remember everything is rated for cover your ass lawsuit, I've rented to mold making machine shops that were running locked rotor ratings of 400 amps on everything totaled up out of a 200 amp 3 phase box that they could hardly get the cover bolted on with no problems, but I know the inspector would never pass it because you're only supposed to use 80% of the total amperage so they're just covering there ass to avoid a lawsuit that's all. Thanks for everyone's advice I do take all of it in 👍


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## O52 (Jan 27, 2019)

65 Tempest schematic.


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## O52 (Jan 27, 2019)

So my next question is; where does the aux panel get its power from? 
battery?
fusebox?
ignition sw?


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## Baaad65 (Aug 29, 2019)

No aux panel, just the extra terminals in the corner of the fuse panel and I'm guilty of double up on a couple of them.


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## O52 (Jan 27, 2019)

ooooo. That kinda explains a lot.

Can you provide a picture of the fuse box with your connections. It sounds like you may be running everything off the ignition circuit and accessory circuits which would explain why the switch is so hot. 

if this is the case you MUST run your amp and fans off a separate panel powered directly off the battery and controlled by relays. 

I’ll refrain from any more conjecture until I get a look at the fusebox.


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## Baaad65 (Aug 29, 2019)

Some terminals are acc some are ignition, I'll get a picture tomorrow...but yesterday is the first time in 4 1/2 years that this has happened.


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## LATECH (Jul 18, 2018)

GTO44 said:


> Op im done. If you want real advice PM me. There is no circumstance inwhich a 10awg wire is acceptable for 100amp alternator.
> 
> To LAtech, im wrapping up a 200k restomod chevelle for an NBA player and the shop is completely full of high end wiring jobs. Do you boo. Wire your cars however you want. When you start giving BS advice to random people is where i have a problem.


I have been working on cars as a profession for 38 years. Master certified.
You arent teaching me anything


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## LATECH (Jul 18, 2018)

Nice 052. 
I guess GM caught there mess up after 1 production year.
whodathunk?

Thanks for posting that .I was not correct...


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## PontiacJim (Dec 29, 2012)

Damn! Where is Stuart, the PY Nazi? Good thing I am not a moderator here on the forums or I would have to ban a couple of you guys for life for being a troll or butting heads on the subject. I would have to ban the OP for 2 weeks because he was the one who posted the original question that turned into a slap fest.

So glad we are not PY. Heated differences are real world, right or wrong. At the end of the day, we are still GTO/Pontiac guys and will move forward to the next post.

"The amount of resistance in a wire increases when the wire is warm. GM engineering data shows about a 25% increase in resistance when wire temperature is increased from 70 degrees to 160 degrees F."

"Please note that simply disconnecting the original alternator wires, and then installing a heavy cable from the alternator directly to the battery, will only make the alternator effective as a “battery charger.” (That happens when running a ONE-WIRE alternator with many factory layouts.) Of course we have to charge the battery, but what about routing power from the alternator to the electrical system? (ignition, lights, and accessories) Power would have to flow from the battery to the junction via the old “charging wire.” And often in a factory-original type harness the “charging wire” is even longer than the wire from the alternator to the junction. And so the result of this ONE-WIRE method would be dimmer lights and overall weak electrical system performance; in fact often worse performance than with the original, correctly wired, small alternator that was standard equipment on the old cars."

*ALTERNATOR WIRING KIT*
_For the GM alternator models:_
*CS-130 (1st generation)*
&
*CS-130D (late 1990’s, into the 2000 and …? years)*​
*8 Feet Lengths of WIRE*

Our Red, *8 gauge* Tuff-Wire is used for the Out-Put circuit. A selection of 8 gauge wire terminals is included for the various options with wiring methods, which are all shown in the manual.
Our Red, *14 gauge *Tuff-Wire is used for the “Remote Voltage Sensing” Hook-Up.
Dark Brown wire, which is the gauge size and color that GM typically used for the “Turn-On” & Warning Light circuit.
* 
OTHER PARTS included in the package*

A 12 gauge Fusible Link Wire kit is included for short-circuit/over-load protection of the 8 gauge Out-Put wire to the alternator.
A RESISTOR is included, which is calibrated to protect voltage regulator electronics (the regulator is within in the alternator).
A DIODE is included, which will be required with MSD 6A box ignition (and with many other similar types of ignition).
Wire terminals and shrinkable tubing is included for the work of wiring the plug-in connector circuits.





__





MadElectrical.com - Mad Enterprises






www.madelectrical.com


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## Baaad65 (Aug 29, 2019)

Thanks PJ, I don't want to tear apart the wire loom so I think I'll just add a #6 or #8 from the alternator to the battery but I still don't know if I should upgrade to a 140 amp alternator, I do have a lot stuff running so guess it can't hurt.


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## LATECH (Jul 18, 2018)

So glad you are not a moderator P Jim LOL


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## LATECH (Jul 18, 2018)

Baaad65 said:


> Thanks PJ, I don't want to tear apart the wire loom so I think I'll just add a #6 or #8 from the alternator to the battery but I still don't know if I should upgrade to a 140 amp alternator, I do have a lot stuff running so guess it can't hurt.


add the total power consumption in amps. Then ,like you eluded to, if you have under 80 % capacity being used total, the 100 amp will be fine.

X2 with PJ one wire alternators suck

10 awg is fine for such a short run. 8AWG is easy enough to use. just overkill IMHO


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## Baaad65 (Aug 29, 2019)

Ok, but it would give me an excuse to buy a nice black alternator 🤣 the 80% I referred to is for residential/commercial applications where if you have a 200amp panel the inspectors only want all of your possible load to equal 180 amps or they will flag it. But I'll go try and add everything up plus I have to remember it's not putting out 100 amps at idle or lower rpms I think it's somewhere around 4000 rpms right?


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## LATECH (Jul 18, 2018)

remember the pulley on the alt is small so 4000 rpms on the engine is a LOT more at the alt
I do not recall what RPM the alt has to turn to achieve full output, but it is likely at or slightly below cruise rpm of the engine. remember the pulley ratio also changes things at the alternator as far as RPM of the alt


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## PontiacJim (Dec 29, 2012)

LATECH said:


> So glad you are not a moderator P Jim LOL


If I was, then I could not be a "dick" or be part of a "passionate disagreement"........... and I hate "politically correct", "its all about the children", "its all about helping the underserved", "being told what I can say or can't say," "those who don't respect 'Freedom of Speech', "socialism", "lawyers", "government/state forced mandates that go against my personal choice", and eggs - I don't like their color, they're slimy, the cooked smell of rotten eggs,and that fact they come out of chicken's butts. I am OK with them in mixes like cakes and such.

LOL


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## LATECH (Jul 18, 2018)

Funny ^^^^ but understandable and a great disposition


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## O52 (Jan 27, 2019)

Baaad65 said:


> Some terminals are acc some are ignition, I'll get a picture tomorrow...but yesterday is the first time in 4 1/2 years that this has happened.


I think you’ve been lucky. And recent ‘perfect storm’ events prove that. 
The fuse box was never intended for high amperage applications for a long operating time. Short time applications such as a convertible top or power windows are only used for a few seconds so they won’t overload the wiring. 
You really should install a separate high amperage fuse panel powered by a 8-10 gauge wire from the battery. Mount it under the hood and control each component by a relay. Power for the relays can be controlled by toggle switches through the battery or accessory fusebox terminal since they are a low amperage components. 
A better set up would have a thermostatic switch for the puller fans instead of a toggle switch.
Your current setup is marginal.


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## Baaad65 (Aug 29, 2019)

Yes I have thought of an auxiliary panel because of what I've added and now it's probably time before something bad happens, I do have everything fused and I like having control with switches that are rated plenty for the fans. But you're right these old cars were never meant for all these extras I'm just not the best at wiring but I can figure it out eventually. What do you think about upgrading the alternator to a 140 amp? What about the stock regulator, it's new but I've heard about solid state ones. And is there some temperature that an alternator should be, I know the more load the hotter it runs and engine temperature effects it but I can never even touch it after driving it, it's as hot as the motor...maybe it's running hotter because of the small charge wire?


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## O52 (Jan 27, 2019)

The alternator will only put out what the demand is. For my car with only a radio and no other power options a 37 amp is more than enough. 
Add 30 Amps for A/C, 30-60 amps for electric fans, xx amount for high powered entertainment systems and you can exceed 100 amps easily. A 140 won’t hurt anything Except your wallet. If I went that route I’d get the internally regulated alternator from a reputable source. No EBay crap. Lots of good sources explaining how to make it work and how to set up a relay operated system for your accessories.





__





MadElectrical.com - Mad Enterprises






www.madelectrical.com


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## Baaad65 (Aug 29, 2019)

Got it, thanks for all the help and I was looking at the same Tuff Stuff one I have maybe in black for 168.00...I'll go add up my load here and see where I'm at.


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## ylwgto (Oct 27, 2009)

This might help...I went through some similar surprise wiring issues when I upgraded my alternator and did an electric fan conversion









wires spliced into alternator charging cable ??


So I just went to upgrade my old alternator battery charge cable to a 6 gauge to accommodate the 100amp alternator I put in. I took the loom off and found 3 wires booger-soldered into the charge cable. It looks like they are part of the harness that goes to the firewall plug in for the fuse...




www.gtoforum.com





The stock alt wire was terrifying the way it was "stock" solder-spliced into the harness. Spent a lot of time correcting that and adapting the bigger gauge wire.


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## Baaad65 (Aug 29, 2019)

Thanks I did see that thread googling around


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## Baaad65 (Aug 29, 2019)

So another electrical question that I mentioned in a different post is I have to run a relay to get 12v to the coil because my new engine harness wasn't labeled that it had a resistor wire, so the relay worked good for a while then I would have to turn the key to acc to kill the motor so it was suggested here it might be worn out even after just two summer's so I installed a new one, it's a diode suppression relay and right out of the box sometimes it doesn't kill the motor and sometimes it does. It's not a big deal I suppose but just would like things to work as they should...any ideas of what's going on and how to cure it? It should be wired right or I would think it wouldn't work at all.


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## Droach6498 (Nov 1, 2020)

Baaad65 said:


> Some terminals are acc some are ignition, I'll get a picture tomorrow...but yesterday is the first time in 4 1/2 years that this has happened.


Boy was that ever some interesting reading! haha, WTF did you start? Just jokin it got serious though dam some dudes take things a bit to personal


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## Baaad65 (Aug 29, 2019)

Ya it was a little crazy, so I just installed a #8 wire(because that's what I had in my shop and saved me from buying 25') from the alternator to the battery. But turns out that didn't help as when had the engine running I turned most things on then put my hand up inside on the ignition switch and a wire was getting hot, turns out it was the pink wire from the ignition switch for the dash lights. So my dumbass thought I could run three fans on that little wire,( queue the eye rolls and head shaking) idk what I was thinking but obviously not much. So I experimented by separating the pusher fans and puller fan and plugging them into separate extra spade terminals marked for courtesy glove box lamp and some other courtesy light, the pusher fan was ok it's 15amps and the fuse is a 20amp fuse stayed cool but the puller fans are 10amps each so that fuse didn't blow but was hot. I think the best bet is running a 10# wire from the battery to the fan switches since they're rated for 30amps each or is it better to run a relay for each set of fans? Then I'll have to look up how to wire the relays, like I said automotive wiring isn't my strong suit obviously.


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## pontrc (Mar 18, 2020)

Baaad65 said:


> Ya it was a little crazy, so I just installed a #8 wire(because that's what I had in my shop and saved me from buying 25') from the alternator to the battery. But turns out that didn't help as when had the engine running I turned most things on then put my hand up inside on the ignition switch and a wire was getting hot, turns out it was the pink wire from the ignition switch for the dash lights. So my dumbass thought I could run three fans on that little wire,( queue the eye rolls and head shaking) idk what I was thinking but obviously not much. So I experimented by separating the pusher fans and puller fan and plugging them into separate extra spade terminals marked for courtesy glove box lamp and some other courtesy light, the pusher fan was ok it's 15amps and the fuse is a 20amp fuse stayed cool but the puller fans are 10amps each so that fuse didn't blow but was hot. I think the best bet is running a 10# wire from the battery to the fan switches since they're rated for 30amps each or is it better to run a relay for each set of fans? Then I'll have to look up how to wire the relays, like I said automotive wiring isn't my strong suit obviously.


Well Bad at least you caught it before it turned for the worst. You will get it straight 👍


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## goat671 (Apr 13, 2019)

As O52 posted previously this is what you need to do. Use relays to run these fans

I think you’ve been lucky. And recent ‘perfect storm’ events prove that.
The fuse box was never intended for high amperage applications for a long operating time. Short time applications such as a convertible top or power windows are only used for a few seconds so they won’t overload the wiring.
You really should install a separate high amperage fuse panel powered by a 8-10 gauge wire from the battery. Mount it under the hood and control each component by a relay. Power for the relays can be controlled by toggle switches through the battery or accessory fusebox terminal since they are a low amperage components.
A better set up would have a thermostatic switch for the puller fans instead of a toggle switch.
Your current setup is marginal.


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## Baaad65 (Aug 29, 2019)

That's my question, if I have switches that are rated for 30 amps each and properly fused do I need relay's, I've read many opinions doing it both ways. The two pusher fans are 10 amps each and the puller fan is 12 amps so I'm wondering if a 10awg wire is ok or if I should be running 2- 12awg wires to the switches or relays?


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## O52 (Jan 27, 2019)

OK. Tough love time.

Adding an extra wire from the battery to the alternator does nothing to solve the problem with the ignition switch. 
REMOVE ALL THE HIGH AMPERAGE ACCESSORIES FROM THE FUSE BOX!!!

The fuse box gets its power from a single 12 gauge wire which is barely sufficient for a stock car. This is why Pontiac added second 12 gauge wire to run pwr seats and windows, and a third to operate the A/C. 

Operating high amperage accessories without a relay will in turn burn the contacts on your toggle switches unless they are rated for 20 amps or more. 

Relays are one of the simplest wiring jobs to do. Read the material others and I have suggested and educate yourself before that beautiful car of your is no more than burn't sheetmetal


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## PontiacJim (Dec 29, 2012)

Since your car is far from original, just add an auxillary fuse block. Easy enough to do. Supply the fuse block with a 12 Volt source independent of the car's wiring harness, add you connections/switches/fuses and you are done. Added a fuse box and auxillary box to my brother's 1948 International seeing they did not have fuse boxes and I rewired the entire truck adding fuses to protect all the wiring like a "modern" car.

Pic #1 is the power wire that is tied into the battery/starter lug and goes into the truck to power the fuse box.

Pic #2 is the fuse box. You can see the red power wire at the base of the box. I used the modern spade type fuses and when they burn out, they have an LED light that will glow telling you which fuse popped. Above that is a power strip/junction. The fused wiring from the fuse box then goes to my power strip/junction. Then on the same lug/connection of the power strip/junction, the wire goes to the light (s) and powers those lights. Makes it easier for me to connect the wires using soldered ends, as well as fast individual testing should I have a light (s)/wiring failure or issue, and makes it easier to replace an individual wire should the need arise.

Pic #3 is a manual 12V shut-off switch I installed between the battery cable coming off the battery, to the switch, then to the starter lug on the starter solenoid. A 12V shut off switch should be wired into any of out older vehicles to protect them from wire fires - which can happen even if you are nowhere near. I have too much time/money invested in my vehicles to have a short catch it on fire and burn it to the ground whether I am in the car or not. And if you put your ride in a garage, is it worth taking a chance in having your house burn up with the car?


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## Baaad65 (Aug 29, 2019)

O52 said:


> OK. Tough love time.
> 
> Adding an extra wire from the battery to the alternator does nothing to solve the problem with the ignition switch.
> REMOVE ALL THE HIGH AMPERAGE ACCESSORIES FROM THE FUSE BOX!!!
> ...


Ok I get that but the wire to the alternator was suggested here and can't hurt now that it's in place and now that I've found my boneheadded mistake I will be correcting it and my switches are Doorman oval ones with the indicator light that are rated at 30 amps, I've heard of relays burning out too since they only cost 3.99. I'm going to run two 12awg wires instead of one 10awg. I'll check what I have plugged into the fuse panel but I'm pretty sure it's low amp stuff like a glove box light, the stereo head unit not the amps, those have a 2awg right to the battery. Thanks for the help.


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## goat671 (Apr 13, 2019)

One reason to use relays is to eliminate the need to run heavy gauge wires from the source to a switch and then to the load. If you use a relay the heavy gauge wire is not needed to the switch.
A low current is used to pull the relay which completes the circuit to the high current device which is wired with the heavy gauge wire.
So follow the advice add an external junction box and wire the relays and fans from this. 

So instead of running two 12 gauge wires from the fans to the switches in the car just use relays.


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## Baaad65 (Aug 29, 2019)

Got it, well I already ran the heavy wires from the fans when I installed them so now I was going run more wires from the battery for a power source instead of trying to tap power out of the fuse box which isn't right, does that make sense?


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## goat671 (Apr 13, 2019)

Baaad65 said:


> Got it, well I already ran the heavy wires from the fans when I installed them so now I was going run more wires from the battery for a power source instead of trying to tap power out of the fuse box which isn't right, does that make sense?


The point is if you used relays you would not need to run any more heavy wires to the switches or the fans.
If you have the correct wires to run the fans what you would do is connect each fan to a relay the switches you have can then be connected to the switch side of the relay.
You will need to run a heavy gauge wire to each relay as the source. So you more than likely have enough wire to complete this since you do not need to run this all the way to the switches.

Instead of lights imagine your fans


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## O52 (Jan 27, 2019)

I use Bosch (made in Germany) relays in all my electrical work. They come in different amperages according to load. Never had one fail. 

I think you're on the right track B65. It's your personal preference to use the 30 Amp switch or relays. 
As mentioned, with relays, you'll reduce your big wire runs and voltage drops. With relays you can run a single 14 gauge wire from the battery terminal on the fusebox, daisy chain to each switch, and then a 14 gauge to each underhood relay from each switch. You want to keep the high amperage wire runs as short as possible. Install the relays after the circuit fuse as shown above. Jims pictures of a fuse panel would work well. 
Mount the relays to the outer fender lip just behind the battery. Short wire run. You can mount the fuse panel on the inner fender near the battery and under the outer fender to reduce clutter. 

The extra wire from the alternator to the battery is a good thing too but wasn't totally related to the ignition switch overheating. In doing all this, your solving several different problems. 
Good winter project! Send pictures of your installation progress and we'll make sure your not fubaring it.


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## Baaad65 (Aug 29, 2019)

Ok I understand, I'll have to see where I can mount the relays out of site and then have to tear apart my wiring to the fans that I hid neatly to do this, that's why I thought it might be easier to run a couple of wires from the battery to the dash switches and if I decide to use relays I would stick them under the dash but your right it's better to keep the power runs short as possible. If I was starting from scratch I would have done it differently....now that I get the concept I'll figure it out, thanks


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## Baaad65 (Aug 29, 2019)

So I'm going to do it right and use the two 30 amp relays and mount them behind the battery for a short battery power run then I can use my two wires that run to the switches as relay triggers. Only thing I have to get straight is getting power to the switches for the indicator lights, looking at diagrams I can pull power out of the fuse block for that to the 12v side of the switches then the acc terminal on the switches is my relay triggers, and keep my switches grounded to chassis like they are now, I'll hack into the fan wiring to install the relays using a chassis ground out there and a short peice of 10awg to power the relays, hopefully that's a big enough wire because I have about 32 amps with all three fans....does that sound right?


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## O52 (Jan 27, 2019)

Sometimes a drawing is easier to describe.

Switch wiring. 12 volts from the fusebox, Battery terminal if you want to operate fans with the key off or Acc with key in the Acc or Run position. OK to use fusebox terminal since the relay load is very small
Connect 12 volts from one switch terminal to the other. 

Light is powered from the load (relay) side, other side to ground.

Add additional switches the same way


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## Baaad65 (Aug 29, 2019)

Maybe my light bulb hasn't gone on yet but is the diagram missing a terminal, shouldn't there be 4 terminals? Where you show relay 1 relay 2 is that going to the fans or is that my short power lead from the battery?


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## O52 (Jan 27, 2019)

Diagram shows a basic 2 terminal switch. Not the relays.

Switches can have 2, 4 or 6 terminals.


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## Baaad65 (Aug 29, 2019)

Ah ok, I took the squares as the relays, I have three pole switches.


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## Baaad65 (Aug 29, 2019)

Ok so I'm rewiring my fans and have a couple questions for you experts, the power from the battery to the #30 terminal on the relays should that be a separate wire to each relay or can I go to one relay then jump to the other relay? The two pusher fans are 9 amps each and the puller fan is 12 amps. I'm thinking that's to much amperage for one #12 wire since those are rated for only 20 amps. Second question is the relay for the two pusher fans has two #87 terminals so do they both close the same so I could put a fan on each one?


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## goat671 (Apr 13, 2019)

I would use 2 12 gauge wires from the bat / fuse one to each relay pin 30, now each relay can provide 20 amps with 12 gauge wire. If you wanted to you could use 14 gauge for the single fan relay.
For the relay to control the two fans use a switched 12 volts to pin 86 this can be a small gauge wire 16 or 18
Pin 85 is ground for the relay coil this can be the same smaller gauge wire as the switched input.
Run a 12 gauge wire from Pin 87 to the first fan + terminal and another 12 gauge wire from this fan to the second fan + terminal. For the ground connections on the fan use 12 or 14 gauge.

For the single fan do the same as above but you can use a step down in gauge for pins 30 and 87 if you want as it is drawing 12 amps 14 gauge is rated for 15 amps

I hope this helps


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## Baaad65 (Aug 29, 2019)

goat671 said:


> I would use 2 12 gauge wires from the bat / fuse one to each relay pin 30, now each relay can provide 20 amps with 12 gauge wire. If you wanted to you could use 14 gauge for the single fan relay.
> For the relay to control the two fans use a switched 12 volts to pin 86 this can be a small gauge wire 16 or 18
> Pin 85 is ground for the relay coil this can be the same smaller gauge wire as the switched input.
> Run a 12 gauge wire from Pin 87 to the first fan + terminal and another 12 gauge wire from this fan to the second fan + terminal. For the ground connections on the fan use 12 or 14 gauge.
> ...





goat671 said:


> I would use 2 12 gauge wires from the bat / fuse one to each relay pin 30, now each relay can provide 20 amps with 12 gauge wire. If you wanted to you could use 14 gauge for the single fan relay.
> For the relay to control the two fans use a switched 12 volts to pin 86 this can be a small gauge wire 16 or 18
> Pin 85 is ground for the relay coil this can be the same smaller gauge wire as the switched input.
> Run a 12 gauge wire from Pin 87 to the first fan + terminal and another 12 gauge wire from this fan to the second fan + terminal. For the ground connections on the fan use 12 or 14 gauge.
> ...


Yes it does thanks, and I knew after I asked about the battery leads to the 30 terminal just was wanted a second opinion. I'm not sure if I got it straight on the two fan relay, it's a 5 pin with two # 87 terminals so I have it wired with each positive from each fan to the two #87 terminals will that work?


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## Baaad65 (Aug 29, 2019)

After researching it some looks like I need a double output relay with an 87 and 87b so I don't end up with three relays....I'm understanding this now, thanks.


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## Baaad65 (Aug 29, 2019)

I have a double output relay from Grainger ordered be here Monday and I separated the battery leads and installed the appropriate fuses, getting there 👍


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## Baaad65 (Aug 29, 2019)

So here's an update on the rewiring of my fans the correct way, waited a week for the double output relay, had to hook the switches to battery because it was the last two terminals left on the fuse block. Also installed a new 140 amp alternator with an #8 wire directly to the battery and new belt, I went with black to match the steering pump but I'm not a 100% sure it looks better than the polished one, oh well. Ran it for about 20 minutes with the fans on and nothing got warm and no fuses blown so hopefully it's all good but we'll see next summer, thanks everyone for the great help in avoiding a disaster, some before and after pix





























👍


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## Baaad65 (Aug 29, 2019)

So what's the consensus on the black alternator vs. the polished, not that I want to spend more money but maybe I could return the black one. Just not sure maybe I have to let it grow on me.


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## Baaad65 (Aug 29, 2019)

My thought was to match the power steering pump and not so much bling but it seems to stand out more than the polished one...I know first world problems.


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## 67ventwindow (Mar 3, 2020)

Baaad65 said:


> My thought was to match the power steering pump and not so much bling but it seems to stand out more than the polished one...I know first world problems.


 The polished looks better. But both need some contrast to the alternator body. But cant even match socks.


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## Baaad65 (Aug 29, 2019)

67ventwindow said:


> The polished looks better. But both need some contrast to the alternator body. But cant even match socks.


Ya I wasn't sure after I put it on, maybe I can swap the polished case onto the 140 amp guts.


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