Wiring question

[Rjpond]

Lately I’ve ejoyed replacing wires on my 55 3/4 ton truck. I’ve started working on the wiring that matches up with the wiring diagram that I have. My 55 is what they say a later model and I wonder if I need a better diagram? My truck has a horn relay, windshield wipers, heater box and other wiring areas that don’t match with the 1955 diagram that I’m using. For instance, my truck’s headlight switch has a wire connected direct to the ignition switch. The corresponding attaching post on my diagram shows a wire running to the ammeter ( which matches my trucks wiring), however it shows the other wire going to the coil and not the ignition? I guess I’m a bit confused.

 

thanks

[bach4660]

out of curiousity as a late 1955 is it a positive ground 12 volt?

[Plymouthy Adams]

in that schematic, your ignition switch shows coil output in words...keep in mind the position of the switch determine connections internally and the drawing just shows input/output...does not mean it is straight wired....

Edited August 12, 2018 by Plymouthy Adams

[Rjpond]

Yes it is a six volt positive ground system. The previous owner had add a second device (like a second selinoid) which a member told me allowed him to add a second six volt battery . So that also complicates things for a novice like me

[Plymouthy Adams]

I believe you are the second poster to picture this added relay....has been a long time since the first posting and I assure I have no clue where to look for that......not even sure the final outcome of the open discussion.  Maybe an avid truck member here saved a link to that thread. 

[Rjpond]

Thank you Plymouthy Adams for your reply regarding the schematic and what it actually shows. I’m pretty sure the wiring is all original so I’ll keep tracking and replacing one wire at a time. I do reference the wiring diagram to make sure I replace with correct gauge wire

[JBNeal]

additional information - Modified Wiring Diagram with Headlight Relays + Turn Signal 

Edited October 17, 2019 by JBNeal
revised link

[Rjpond]

Thanks guys for the good info and help

[kencombs]

8 hours ago, bach4660 said:

out of curiousity as a late 1955 is it a positive ground 12 volt?

 

the answer below indicates it is still 6v.  At least that's the way I understand it.  OP, can you clarify?  Kind of reading between the line it seem the batteries are in series for start, parallel for run, is that the reason for the relay??

[Rjpond]

Yeah, I did a poor job answering the member’s question on if it’s a 12 volt system. It is a six volt system with positive ground. The truck had one six volt battery in the battery box mounted to the frame and a second  battery was mounted under the hood. I’m not sure why the two batteries ,maybe for better starting in winter weather? I plan to keep it six volts with only one battery

[Jj1981]

When I got my b2b it had a second  battery under hood also that was wired to the starter and the lights 

[Rjpond]

Do you still run the two battery set up?

[Jj1981]

I am converting to 12 volt