Electrical Circuit ??

[55 Fargo]

I just re-wired the headlight/park light circuit.

I did use the OEM switch with a 30 amp circuit breaker rated at 12 volts, but I do believe these work for 6-24 volts.

All is well, my set-up is 12 volts, the dash lights, the park lights and headlights all working very well, all have 12 volt bulbs now. The park and headlights have a ll new ground wires too.

Because I am not installing a fuse panel, is the 30 amp circuit breaker enough to protect this circuit, or should I install a in-line fuse prior to the circuit breaker, from my hot lead to the light switch.

The amperage load should be 1/2 of a 6 volt set-up, and I still used 12/14 gauge wire, for all, I did also use a block terminal under hood to supply the current to the front lights, to use less wire.

My next step is to install a 7 wire universal signal switch, for the signal/brake light circuits, plan to use 16 gauge wire and lED bulbs for that, witha n electronic 3 terminal flasher.

My alternaotr is rated 55 amp, I do not pkan any heavy loads for juice, but will havea heater motor, stereo, but no AC or power windows.....

[TodFitch]

The fuse or circuit breaker should trip before other parts of the system are damaged. If you used the same wire size as for 6v then the wires can safely handle the same amperage as before. Assuming the factory thought a 30 amp breaker was adequate for the wiring, that is still true.

[55 Fargo]

The fuse or circuit breaker should trip before other parts of the system are damaged. If you used the same wire size as for 6v then the wires can safely handle the same amperage as before. Assuming the factory thought a 30 amp breaker was adequate for the wiring, that is still true.

Okay, thanx Tod, other item I noticed that is different, is on the trucks light switch, the park lights go on first as per usual, but they go off, when the headlights are pulled on, not sure if that is correct, on this application or not, I personally like the park lights on with the head lights.....

[Young Ed]

Thats the way my car is wired too.

[55 Fargo]

Thats the way my car is wired too.

Hi Ed, my 47 Chrysler, think the park light stay on with headlights, maybe I wired it in the wrong way, but like it that way. Gonna go check, and see if that is the case....The truck, has a dimmer switch for the instrument panel, which is kinda neat...

[TodFitch]

Okay, thanx Tod, other item I noticed that is different, is on the trucks light switch, the park lights go on first as per usual, but they go off, when the headlights are pulled on, not sure if that is correct, on this application or not, I personally like the park lights on with the head lights.....

The parking lights on my '33 turn off when the headlights turn on. Dredging up old memories, I'm pretty certain that the '63 Plymouth I learned to drive on and the '63 Dodge D200 pick up I had a long time ago both had the parking lights turn off when the headlights came on. I think that having the parking lights stay on became standard in the late 1960s.

[55 Fargo]

47 Chrysler lights, park lights on first pull, the next pull, headlights and park lights , maybe a luxury car thing, fine with me......

[Don Coatney]

I think that having the parking lights stay on became standard in the late 1960s.

I recall first seeing parking lights and headlights both on in 1963 or 64 when I was in high school. I thought it looked so cool:cool: When I get around to re-wiring my car I will go that route.

[TodFitch]

I recall first seeing parking lights and headlights both on in 1963 or 64 when I was in high school. I thought it looked so cool:cool: When I get around to re-wiring my car I will go that route.

Doing some searching around, it seems that some makes and models started doing that in the early to mid-1960s. From http://www.valiant.org/electrical.html it sounds like it became required in 1968:

Chris North wrote: Until 1968, the parking lights on US cars normally went off when the headlights were turned on. The early Plymouth Barracuda put a jumper between the tail light terminal and the parking light terminal on the plug that attaches to the headlight switch, to make the parking lights stay on when the headlights were turned on. For your Valiant, you can remove the headlight switch and solder a jumper wire between the "P" and "R" terminals on your headlight switch to keep the parking lights on with the headlights.

Sounds like it was the same for Ford: http://forums.vintage-mustang.com/vintage-mustang-forum/567568-do-parking-lights-come-headlights.html This pretty well matches up with my memories of the era.

As for my '33, the parking lights are inside the headlight assembly on the headlight reflector and I doubt that you could see their little 3cp output against the 50cp output of the adjacent headlight bulbs. So I think I'll keep the stock set up on that.

Edited February 24, 2012 by TodFitch

[55 Fargo]

Doing some searching around, it seems that some makes and models started doing that in the early to mid-1960s. From http://www.valiant.org/electrical.html it sounds like it became required in 1968:

Sounds like it was the same for Ford: http://forums.vintage-mustang.com/vintage-mustang-forum/567568-do-parking-lights-come-headlights.html This pretty well matches up with my memories of the era.

As for my '33, the parking lights are inside the headlight assembly on the headlight reflector and I doubt that you could see their little 3cp output against the 50cp output of the adjacent headlight bulbs. So I think I'll keep the stock set up on that.

I know I have the OEM light switch for my 47 Chrysler, and the park and headlights go on together, and the park lights go on by themselves only on the 1st part of the light switch, is that the way it should be, if so, did the upper lines of Chrysler do this specifically....

BTW, just came from a short ride with the 56 Fargo, it is dark here now. The 12 volt 45/55 watt headlights illuminate very well. The 12 volt bulbs in the speedo and instrument panel are working well indeed too.

Very pleased with this. Now to wire in the brake light/signal circuit, and gas gauge etc....

Edited February 24, 2012 by Rockwood

[Don Coatney]

I know I have the OEM light switch for my 47 Chrysler, and the park and headlights go on together, and the park lights go on by themselves only on the 1st part of the light switch, is that the way it should be, ....

I dont think so.

[TodFitch]

I know I have the OEM light switch for my 47 Chrysler, and the park and headlights go on together, and the park lights go on by themselves only on the 1st part of the light switch, is that the way it should be, if so, did the upper lines of Chrysler do this specifically....

You can easily wire any of the cars I've seen to have the parking light come on with the headlights: Just connect the front parking light wire to the tail light terminal on the headlight switch. Depending on your access under the dash and if the switch uses screw type connectors or not, its something like a two minute job. With screw type terminals where you can easily connect two wires instead of one to a post you don't need any new connectors, switches, etc. Wouldn't surprise me if lots of older cars have had that simple mod. It would surprise me some if a 1940s car came from the factory that way...

[Young Ed]

Doing some searching around, it seems that some makes and models started doing that in the early to mid-1960s. From http://www.valiant.org/electrical.html it sounds like it became required in 1968:

That would be the same year side marker lights became law. The two things might have been part of the same law.

[55 Fargo]

You can easily wire any of the cars I've seen to have the parking light come on with the headlights: Just connect the front parking light wire to the tail light terminal on the headlight switch. Depending on your access under the dash and if the switch uses screw type connectors or not, its something like a two minute job. With screw type terminals where you can easily connect two wires instead of one to a post you don't need any new connectors, switches, etc. Wouldn't surprise me if lots of older cars have had that simple mod. It would surprise me some if a 1940s car came from the factory that way...

Oh okay, something I musta done, well it works for me.

I dont think so.

Again, inadvertently, wired my 47 to have both park and headlights on the same time....

Edited February 24, 2012 by Rockwood

[Don Coatney]

As I said I will wire my lights to work that way when I re-wire my car.

[55 Fargo]

Wired in fuel gauge today.

Now this was a fun job, but did not take very long either, so 6 of this and 1/2 a dozen of the other.

The fuel tank sender unit has not access, so there is a few inches of clearance above the tank under the cab floor.

I could not undo the sender unit terminal screw, so cut the old wire, and left a few inches, and ran wire from this point, by using a butt terminal, and shrink tubing.

Went to attach wire to back of fuel gauge, and noticed no needle, oh yah, thats why there was some kinda old gas gauge attached to bottom of the dash.

I am in luck though, have a parts truck, and grab the cluster, and pull out gas gauge, simple enough right?

Well now I have to take fuel gauge out of cluster under truck dash, came out fairly easy, but installing donor gauge was not as easy, so played around for a 1/2 hour, finally all mounted into place, whew, go lucky, this would be a real pain under a P15 or C38 dash, the 55 Dodge truck is much more forgiving.

Powered up the truck, and fuel gauge indicated 1/8 of a tank, about right, as there is about 2 gallons of gas in the tank, as I had just poured some in yesterday.

So that went well, and no issue was noticed by using 12 volt negative ground, on this gauge, whicih is either from a 1956(12v) or a 1955(6v+), either way it works so far, will see with more fuel in the tank......

[TodFitch]

...So that went well, and no issue was noticed by using 12 volt negative ground, on this gauge, whicih is either from a 1956(12v) or a 1955(6v+), either way it works so far, will see with more fuel in the tank......

I think the fuel gauges were 6v long after the vehicle electrical when to 12v. At least the '63 Dodge D200 I once had used a voltage reducer that was in one gauge to power other gauges. Can't remember right off if the reducer was in the temperature gauge or the gas gauge, but it was in one of them.

You might want to consider using a voltage drop resistor in-line with the power to the fuel gauge to reduce the power it needs to dissipate. Might help extend its life. The ones I've seen are all based on differential resistance/current so they are pretty insensitive to input voltage and will read correctly over a wide range of voltages. But if it will work on 6v or 8v instead of 12v the insides of the dash unit will stay cooler and probably last longer.

[55 Fargo]

I think the fuel gauges were 6v long after the vehicle electrical when to 12v. At least the '63 Dodge D200 I once had used a voltage reducer that was in one gauge to power other gauges. Can't remember right off if the reducer was in the temperature gauge or the gas gauge, but it was in one of them.

You might want to consider using a voltage drop resistor in-line with the power to the fuel gauge to reduce the power it needs to dissipate. Might help extend its life. The ones I've seen are all based on differential resistance/current so they are pretty insensitive to input voltage and will read correctly over a wide range of voltages. But if it will work on 6v or 8v instead of 12v the insides of the dash unit will stay cooler and probably last longer.

Thanx Tod, would think a Runtz type volt dropper, should work on ths gauge

[ggdad1951]

My truck has an access hole w/ plug under the seat above the sender to do that wire attaching...does yours not?

[TodFitch]

Thanx Tod, would think a Runtz type volt dropper, should work on ths gauge

Well a web search turns up a Runtz unit that supplies 4 amps which is way over kill. So it would work but the price on the site I found one was $18.

I'd just measure the resistance between the power input to the dash gauge and ground (resistance of the total fuel gauge system). To cut the voltage in half you'll need to put a resistor of the same value in series with power wire to the gauge. The resistor will be dropping 6 or 7 volts and you'll know the resistance so calculate out the power it needs to dissipate and thus what wattage resistor to use. Probably available at Radio Shack for pretty cheap.

[55 Fargo]

My truck has an access hole w/ plug under the seat above the sender to do that wire attaching...does yours not?

No it does not, or I would have accessed through it.

What year is your truck??

[55 Fargo]

Pics on dirt road near field, near my property. It is very cold out today, as compared to lately, about 0f with windchill.

Truck with headlights on, and with park lights on....

[Dave72dt]

No it does not, or I would have accessed through it.

What year is your truck??

'51