Hello all,

I was just looking at my starter button mounted in the dash and I saw it only had a 1 wire hookup. I was expecting to see 2, one with power from the key and one to feed the solenoid to engage the starter motor while the button was pushed. It is currently unhooked right now so I cant trace the wire to figure out where it goes. I looked on a wiring diagram it it looks like the 1 wire goes to the little stud on the solenoid. The truck has been converted to 12 volt, I am assuming negative ground.I just dont see how this would engage the starter if it isnt connected to the battery in any way. Anyone know how to hook this up the right way before I blow something up?

Thanks!!!

 

It goes to ground and completes the circuit

 

That makes sense, so the wire from the push button goes to one of the little posts on the solenoid and the ignition switch must be where the hot comes from to power up the solenoid to engage the starter. Does the wire from the key go to the other little post on the solenoid?

 

If you solenoid has two small posts then you a non stock solenoid. It should only have one small post. The two post is energized by applying power to one stud and grounding the other stud.

The original circuit is as Dick described. The push button's case is grounded to the dash and when pushed in provides a ground to the solenoid. The power to the solenoid's magnetic coil is internally wired. The newer, two post solenoid isn't.

There's a post on the original stock ignition switch has a post that has a wire connected to the (-) post on the coil. Remember originally your truck was negative grounded.

 

I just ran down and looked, it is just a 1 little post solenoid. Sounds like I just run 1 wire from the push button to the little stud and I am done. I am not used to this negative ground setup. It has been converted to 12 volt so I think I just have to wire the ignition switch a little differently. I will run power from the battery to 1 side of the switch and then to the positive side of the coil. Will that work?

 

Whoa, Bob!

I believe a stock '51 solenoid will only have one terminal, and it will be looking for power, not ground. That's a change from 48-50's, can't remember if it was changed in '51 or '52.

If there is a two-post solenoid, like much more modern Fords, one is power to energize the solenoid ("S" I believe), the other is a ballast resistor bypass to the coil ("I") while cranking.

"Remember originally your truck was wired POSITIVE ground"

 

My stock 51 has the starter button taking ground to the single small post on the starter relay (positive ground).

The starter motor will turn whether the ignition key is on or off (the truck won't start if it's off) because the starter button completes the circuit from the battery to the starter motor through the starter relay. No power goes to the coil if the ignition switch is off.

 

Ross,

You're correct, I'm sorry for the misinformation. I didn't know about the switch in the solenoid, I just assume the trucks I had were all set up the same. None of the '51-52s I had were operable, only parts trucks. I must have been thinking positive but typed negative. I remember thinking to myself, as I was typing, that the our old Ford were backwards from the later cars and truck.

Sorry guys.

 

Ross, now I am reconfused. Do I just run a wire from the starter button to the little post on the solenoid?

 

It sounds from JR Joe's post that the change was made in '52. Check the '51 wiring diagram on VanPelt's site, and check your solenoid by putting either a ground to the little terminal or jumping to it from the battery side of the solenoid.

 

Yes, that's correct if it's the original style solenoid.
Was the solenoid swapped out when the system was converted to 12V?
And, it doesn't matter whether it's negative or positive ground, it works the same way.
My 6V system is changed over to negative ground, and the only things that need to change to do that are the direction of wire through the ammeter and the position of the wires on the coil.

 

Jonas,

I don't think the solenoid has been replaced. I think all the guy did was throw a 12volt battery in the truck and just go. I think this because none of the gauges or lights work, like they were burnt out.

As far as the key goes, does it have power in and then power out to the other side of the coil?

 

1948/51

21A-11450 .. Starter Solenoid / 6A-11450 .. Starter Button.
------------------------------------------------------------
1952/55

B5A-11450-A .. Starter Solenoid / 2C-11500 .. Starter Button.

The 2C starter button was also used as a windshield washer actuating switch for 1965/66 F100/250's and is still available from Ford.

 

I'm in the same boat you are in. I converted my dads 46 truck to 12 volt. It has a new 2 post solenoid on it. Im leaving the push button on it and need to know where it goes to. This is the second go around. I have a 12 volt generator on it and its not charging right. I had it checked once and it was good, so know Im trying to figure this wiring out. My gen and voltage reg is hooked up right and the truck starts fine, it just willnt charge.

 

Is the regulator for a neg ground 12v vehicle? Did you polarize the generator after install?