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can't believe i am asking this

Hey guys, really need some help here. I haven't been able to do much of anything to my f1 since i got it, not even pics. I'm trying to move it now and need some advice. It came with no battery, and I'm not familiar with positive ground systems. Tying to figure out if it even is... Please tell me if this sounds right... One battery cable going from engine block to positive terminal on battery. Negative post of battery going to right hand side of starter solenoid. Sound right?
 

Fellro

Moderator
Staff member
That would be a positive ground...
 

O'Rattlecan

Redneck Prognosticator
26,689
797
Belton, MO
Wow, was that stock? Does anyone know? I've never heard of such a thing.

Ryan
 

fatherdoug

Tonto Papadapolous
I believe Ford trucks were positive ground until the mid-50's. I do know our '58 F100 had a 12V Negative ground system.
 

Fellro

Moderator
Staff member
It was pretty common way back. But it really doesn't work that much different than 12v neg ground. The current flows essentially the same, as the polarity is technically the same, it just gets hooked up on the opposite cable. The actual flow direction is backwards of the conventional thinking. Generally, the common thought is that it flows positive to negative, but actually, the positive is the receptacle.
 

mtflat

Flatheads Forever
2,559
147
From memory, I think it was '56 when Ford switched from 6V pos to neg grnd.

Funny reading the comments of the young guys here. I work so much in this older world that I had forgotten everyone doesn't understand it. Thanks for the smiles this morning.

When I rebuilt my '48 F1 I switched to 12V neg mainly to take advantage of newer accessories. 6V requires wiring twice as heavy as 12 due to lower voltage but higher amps being drawn thru the wires.
 
Thanks a lot for all the responses guys. "Opposite of conventional", well at least conventional now, that's how I've been trying to force myself to think of it. I just have to keep reminding myself that it's not negative ground, gonna have to kinda relearn how i diag electrical issues for this one. Well as long as it's hooked up right i can now roller that out, but still having a problem. Now it's basically just a no crank no start condition. I should be able to figure out where the problem is but i'm just looking for some reassurance here, positive ground or negative ground, I'm using my test light the same way right? Clip it to a solid ground and start testing posts, wires and terminals, right? I can't get the starter relay to click, nor can i jump it for some reason. I turn the key on, hit the starter button and nothing... Any further direction or advice would be appreciated, and by the way, I'm using a 12 volt battery, i don't think that's a big deal just to get it started and moved 20 feet but I'll let you guys tell me that answer if you don't mind:)
 

mtflat

Flatheads Forever
2,559
147
Yes, your test light will work the same way on either system. An analog multi-meter will sweep backward - if you use one of these connect black to Pos and red to ground.

Connections have to be clean and tight, especially with 6V. It's pains-taking work but go over every electrical connection on the starting circuit... disassemble, clean/sand and reconnect.

Grounds are critical. Stock oem should have a positive ground from battery to block, block to firewall, body to frame. Negative goes to solenoid, solenoid to starter like normal. The starter button allows the circuit to collapse in the solenoid sending juice to the starter.

To help wrap your mind around it, all wiring is conventional - just the battery terminals are reversed.

If you wish to convert to 12v someday, this tutorial is what I followed: scroll down to "converting 6 to 12"
http://www.patricksantiquecars.com/articles.html
 
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Thanks mt flat, very clearly stated, appreciate it. I'll do exactly that, check/clean all connections. Funny thing i just noticed is that both sides of my start button have power, without me pressing the button:headbang: strange...
 

fatherdoug

Tonto Papadapolous
Yes, your test light will work the same way on either system. An analog multi-meter will sweep backward - if you use one of these connect black to Pos and red to ground.

Connections have to be clean and tight, especially with 6V. It's pains-taking work but go over every electrical connection on the starting circuit... disassemble, clean/sand and reconnect.

Grounds are critical. Stock oem should have a positive ground from battery to block, block to firewall, body to frame. Negative goes to solenoid, solenoid to starter like normal. The starter button allows the circuit to collapse in the solenoid sending juice to the starter.

To help wrap your mind around it, all wiring is conventional - just the battery terminals are reversed.

If you wish to convert to 12v someday, this tutorial is what I followed: scroll down to "converting 6 to 12"
http://www.patricksantiquecars.com/articles.html

Tim, I wanted to read all about 6v/12v conversions, but alas, the error message says the domain registration expired on June 6. :(
 

dustybumpers

don't play well w others
12 volt will fry your gas guage. be sure to unhook it, and the sending unit before you get too much testing into it.
 
Will do, one of the things I feel like I'm getting conflicting info on is if the starter button is supposed to be giving ground to the single post on the solenoid or power. Again my truck ids a 51, i've heard both though...
 

dustybumpers

don't play well w others
51 is a funny year. One of my Farmall tractors is Pos ground, the other is Neg ground.
Trust only what you see.
 

mtflat

Flatheads Forever
2,559
147
Thanks mt flat, very clearly stated, appreciate it. I'll do exactly that, check/clean all connections. Funny thing i just noticed is that both sides of my start button have power, without me pressing the button:headbang: strange...

Oh, you have the late style button with two wires. Mine are the earlier single wire button that grounds to the dash.

Sounds like your button may be stuck "ON" for it to have power on both sides. They're relatively inexpensive - I'd opt for a new one and see what happens.
 
No, i know what you mean but i tested the switch, i have power on both sides and continuity but not because of the switch, it's strange but that's how it is. Almost seems like previous owner had tried to bypass either the ignition switch or the start button, not sure... Just picked up a 6 volt battery today, gonna put it in this weekend and see what i have...
 

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