1959 GMC foot start wiring

[Sammy4358]

Does anyone know what to do with the black and purple wires that would go to the solenoid top and side lug on the starter when you have a foot pedal for the starter? Does one connect with the positive battery cable attached to the starter and cap the other?

[1project2many]

The purple wire would not exist on a foot pedal truck. It is the wire from the key "start" position to the starter solenoid. Black wire carries power from the battery connection at the starter to the ignition switch. You need that one.

[Sammy4358]

Thanks for the info, I have one wiring diagram showing the purple wire connected to the bolt that holds the foot pedal pivot arm on the starter, so it would be grounded. I guess the start position on the key switch would connect the solenoid to the ground to complete the circuit anyway so I should not short out my ignition switch, I hope!!!

[mr48chev]

Edited,

Reading subsequent posts brought up that the Black wire should be the power supply to the inside of the truck connecting to the ammeter if it connects to the large stud that the battery cable connects to.

The resistor by pass would normally connect to the I post on the solenoid and run to the coil.

[Foot Stomper]

If you have a factory foot stomp start, you should not have a start position on your ignition switch.

[Sammy4358]

Total restoration, new wiring harness and the I cannot find an original ignition switch, the reproduction dealers say they are for this truck but all have the start switch. I purchased one from Jim Carter that only has the on & ACC position but it won't fit in the factory hole or use the correct key cylinder. If you know where I can find a real ignition switch for this truck, that would be wonderful.
Thanks

[1project2many]

Do not connect the purple wire to ground. If you are using a switch with "Start" position my advice is not to connect any wires to the start terminal.

[Sammy4358]

Thanks for the info, you probably saved my ignition switch

[Foot Stomper]

Hope this helps.

[dsraven]

does your starter solenoid switch look like this, with a small terminal on the side? the black wire would go there and up to the coil (+). the black wire gives the coil full power when the starter is engaged for a nice hot spark. when the foot pedal is released the ign switch feeds power to the coil through a ballast resistor to reduce voltage to the coil when running. otherwise the ign contact points, condensor and coil burn out prematurely. battery cable pos goes on the larger terminal at the starter. purple wire gets capped and shrink tubed on both ends, if your harness has it, because it would normally feed the starter solenoid from the key switch on the dash if you didn't have a pedal operated starter. yours has foot pedal linkage that pushes against the button on this switch to give the starter motor power when pushed. the linkage also pushes the starter drive into the flywheel ring gear when the lever is moved towards the switch button. make sure there is free moving linkage and a return spring on the pedal linkage.

see the pic and starter info here when you scroll down

http://oldchevytrucks.com/blog/index...ag/mechanical/

here is the switch with the terminal for the ign coil

https://www.classicparts.com/1947-59...ctinfo/53-712/

hope that helps you out.

[Sammy4358]

My starter looks just like the second one on the Jim Carter site but it does not have the side lug, only the big lug on top for the battery cable. My truck is a GMC with the original 270 six
Thanks

[1project2many]

The black wire is battery power. I said it was to ignition switch but it actually connects to ammeter.

The purple wire is not used. It's to power the solenoid.

If your truck used a resistor bypass wire it would have been dark green. On the switch with the side terminal in the pictures above, the green wire goes from the side terminal to coil +.

There should be a tan wire from ignition switch to resistor, and a green wire from resistor to coil + also.

The wiring diagram previously posted shows the black wire from the battery connection at the starter to the back of the ammeter.

[mr48chev]

Well done 1project2many. We need to save that for reference.

I had qualms about even mentioning it but you could on that truck run the resistor bypass wire off the start pole on the switch to the + post of the coil rather than using the push button I mentioned earlier.

Now I probably have to edit another post.

[dsraven]

sorry guys, I shouldn't have mentioned wire colors because the op said he has a new wiring harness. you never know if the colors are gonna be the same as factory or not.
good catch 1project
at least I gave directions on where the wire goes, even if the color is wrong....good thing you guys proof read my post.

[1project2many]

at least I gave directions on where the wire goes, even if the color is wrong....good thing you guys proof read my post.

Lol... You put a ton of effort into providing helpful and thorough explanations for folks. Don't beat yourself up over a missed wire color.

sorry guys, I shouldn't have mentioned wire colors because the op said he has a new wiring harness. you never know if the colors are gonna be the same as factory or not.

Good point. Aftermarket harnesses don't always follow original color codes.

[Sammy4358]

The advertisement for this wiring harness stated( this is the easiest harness to wire on the market) and it was pretty straight forward except for the above mentioned purple wire.
Thanks for all your help

[mr48chev]

When you have no real need for the purple wire as it was designed for that can be confusing.

If you used the start position on the key switch as the resistor bypass that would simplify things and you just hold the switch to start and hit the stomp pedal letting off both at the same time. No added motions or extra switches or wires.

If you don't need a resistor bypass you just don't hook it up. just neatly hide the wire in the harness so it would be there if you ever decided to use a starter that needed the key switch.

[Sammy4358]

We did a test run on the engine after rebuilding her with only a wire from the battery to the top of the resister and she cranked and ran fine with no booster voltage for starting. She has been running for 60 years without that darn purple wire, so I guess I'll keep her that way.

[dsraven]

purple was probably just an extra for those guys that use the key start. that way the harness maker gets coverage for both styles with a single part number.
I recommend to shrink tube the ends of the purple wire. that way when you are under there someday (or somebody else is) you won't wonder what it's for. it also looks finished and not like something isn't finished.