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12 volt conversion wiring diagram

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So I have decided to switch my 53 B4C over to 12 volts.  Here is a wiring diagram I plan to follow when redoing the harness.  This assumes a one wire alternator, changing the heater motor to a 12 volt motor, change the horn to 12 volts, and add relays for the fog lights and one each for the high and low beams. Also switching the wiring on the Ammeter and the coil (a 12 volt coil with PerTronix ignition.  Also a blade style fuse box.  Anyone see anything I missed?  Thanks in advance for your help and if this looks good maybe it could help others make the switch to 12 volts.

12 volt wiring diagram.jpg

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One relay would work but some of the sites about relays advise one for low and one for high to maximize the benefit. I am open to any thoughts on the subject.

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Are the sites that give this advice the ones who sell the relays? I could understand how that could maximize there benefit. But it is your vehicle. Do what you are most comfortable with.

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Hey there, relays for both high and low, plus fog lights, so a lot of circuit security, relieving any of the switches in the circuits to become overtaxed.

I think it's a bit "overkill" , but then I am comfortable with a fused circuits, and  1 relay for my headlights.

Hopefully those with some real wiring experience might chime in, lot's of conjecture on this website on a occasion for certain topics, so take it all with a grain of salt. Good luck.

BTW I looked at your "schematic" and it will be a very fine system, and most likely you will never have overload issues and burnt wires.....Good Luck

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Found something that may be a bit nit picky while measuring for new wires.  On the wiring diagram there is a brown wire going from the ignition to both the light switch and the ammeter.  However, when I look at the wiring on my truck the brown wire goes from the ignition to the light switch and then to the ammeter. (see the photo below)  The double connect on the wiring diagram is at the ignition while what I found is the double connect on the light switch.  Not sure any of this make any difference but I thought it was an interesting difference.  I am pretty sure none of these wires have been replaced and looking at the condition and coloring the brown wire certainly looks factory.  I think I will follow what I found when remaking the wiring as it worked just fine connected this way for many years.

ignition detail.gif

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interesting. as you pointed out, it is electrically the same point...altered by PO or a running change in production after the schematics were drawn...who knows..you realize it is the same point..follow your own lead on what way to go back.  Either way who but you would know?  Good to make progress...

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Just rewired my 51 Pilothouse for a few hundred dollars, I ordered a universal kit that addressed all concerns. Wiring was all pre-labeled for what went where. For the money and effort, I would suggest doing the same. New wiring, and changing over the 6 volt, alternator included, all for $500.00? I'm in!

June_1.jpg

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I wired my truck two times, fire took the first harness. Now I have used a kit to wire my suburban. For me neither was an easy experience. Should I wire another vehicle, I would run a simple hot  wire harness for the engine, and a simple separate harness for the head and . tail lights. All the other wires are options nice to have but not required. Wiring for dash lights, wire for fuel gauge, horn, ,heater, wiper motor,  etc. 

last week i fried the harness in my truck. I think one wire shorted out, maybe a cut in the wire, it got hot and melted through successive wires.  I disconnected the battery and closed the doors. So I have a project when I get home. 

Don C taught me this, use washer locks on every stud that requires a nut. If you do not, the viabration will work the nuts loose. I learned this the hard way. Whatever you do, best to you. 

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As far as the horn goes, you don't need to change that to a 12 volt.  Just use a series of diodes in the wire from your source to the horn to lower the voltage, keep the original horn.  

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Diodes? Did you mean resistors? If so did not work for me as the dual horns use too many amps for the resistors that I could afford. If there is a way to do this I would like to know, otherwise the  6 volt horns work on 12 volts just very loud! Just change the horn relay and use very heavy wire to and from the relay. Some horn tuning may be required.

DJ

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Use 6 amp diodes, each diode drops the voltage .7 volts.  Just splice the wire between your amp meter and the horn and solder the diodes in.  I've tried both resistors and diodes and diodes work best for me.

http://www.ebay.com/itm/132114125153?_trksid=p2057872.m2749.l2648&ssPageName=STRK%3AMEBIDX%3AIT

Here are some rated 10 amp that will work also if you don't mind the waiting time for shipping.

http://www.ebay.com/itm/20x-10A10-10Amp-1000V-10A-1KV-R-6-MIC-General-Purpose-Axial-Rectifier-Diodes/182323218419?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D2%26asc%3D41376%26meid%3D45b4d1dff37a44519a1846652932ccf3%26pid%3D100005%26rk%3D3%26rkt%3D6%26mehot%3Dag%26sd%3D132114125153

Edited by Dennis46PU

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On 6/5/2017 at 5:30 PM, RonaldC said:

New wiring, and changing over the 6 volt, alternator included

@RonaldC  : Who did you purchase the package from?

Edited by medium_jon

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4 hours ago, Plymouthy Adams said:

how does this stand up to some impatient driver stuck in traffic with a heavy palm laying on the button..heat dissipation is my question...?

Actually haven't had any trouble but haven't been impatient in traffic to know that.  How many amps does the horn in our trucks WC and pilot house models draw?  I know my Ames horn in a different car pulls 4 to 5 amps and while in parades it gets used a lot.  Heat has never been a problem with 6 amp diodes, however in the future I will probably use 10 amp the next time.  

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I could be wrong, but this seems like a good place to ask this question:

As per photo below, is the trans mount bolt a good place for the Neg Grnd on a 12V coversion just beginning?

It's nice and close to where the Batt Neg will end up.

 

NEG_GRND_on_Trans_.JPG

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http://www.ebay.com/itm/WIPER-and-other-Accessory-VOLTAGE-DROP-12-volt-to-6-volt/260805627953?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2055119.m1438.l2649

Remember to wire the amp gauge backwards from original. I doesn't care how much voltage it reads.

Drop the voltage to the fuel gauge or you'll burn it up. Also, wire it backwards.

Just too much work converting to 12.

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Not sure how I didnt catch questions directed to me. Sorry guys.

 

I purchased Highway 15 from Yogi's online. Great kit. Only had to reach out to tech support a couple times as I needed clarification on how to keep the floor start, and do it the correct way. Would recommend the same purchase to others. Just make sure the 15 circuit suits your needs, now and any future upgrades.

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Hi do you plan to run the 6v starter with 12v or do you change it?

Im looking for a 12v modern starter that fits, do you know any?

Thanks 

Otto

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