Rewiring my 40 random questions

busmania

busmania

Well-known member
Moving along on my 40. I have never wired a car. Wiring and electrical has always been the one thing I avoid on a car. But not this time. I will be wiring my car from scratch with Rhode Island wiring parts. I layed it all out the other day with and with their diagrams on each harness, it looks pretty straight forward. This thread is for the millions of questions the google machine won't have answers for. I appreciate y'alls help!

Details
40 ford coupe
12 v negative ground
Rhode Island wiring
1 wire alternator
turn signals
mostly stock'ish
Stromberg efire distributor

First up, starter. I am hoping to get my freshly rebuilt flathead fired up first before I really move on to the rest of the car wiring. This is my first ford. Do I need a starter relay on the firewall? does 6v or 12v matter? Is there a generic ford relay I can use for 12v?
 
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Yes, you’ll need a 12v starter solenoid. You can buy one at NAPA. They can look up the stock part, and just order the 12v version.

When I wired my 41 pickup, it was slightly less easy than my 57 oval window Beetle. Which is still pretty easy. You are correct, it’s pretty straightforward.
 
While your rewiring it, it's neat to install a 12V LED light under the dash that will light up the passenger floor area at night when headlights are on.
 
Congrats, You have one of if the best wire looms made. I know you will need a starter solenoid that activates when you ground the small terminal. Most 12volts activate when you apply power to that terminal. If you follow their instructions it will be a snap and work flawlessly . I put one in my 46 Cadillac and it was easy. Tim
 
If I was installing a new starter relay I would try getting one with the button to spin the starter.
 
They have a button on the bottom that acts as a second starter button. So you can turn the engine over while working in the engine bay. You can get new ones like this too.
 
Fritz said:
They have a button on the bottom that acts as a second starter button. So you can turn the engine over while working in the engine bay. You can get new ones like this too.
Click to expand...
64-10021.jpg
 
I found plenty of 6v relays with the button at Napa but no 12v so for now I’m moving on. I want to try and start the engine maybe today. Question on wiring a few things.

Started relay. - positive from battery to one side, other side goes to starter, correct? What goes to the small terminal in the middle?

I am making a small gauge panel with a on/off switch and starter button. The on/off. Do I just run my coil wire to here and the to ? Where? Where do I run the push button wires?

I know this is really basic stuff I’m just not great with electrical stuff. Thanks y’all.
 
6volt Ford relay has been working fine for years on 12 volts for me. Be sure to mount it with the button on the bottom so gravity helps to breaks the circuit or they sometimes stick on
 
I have had a random (I have no idea what voltage it was originally for) solenoid on my engine test stand for years. I run both 6 volt and 12 volt systems and it hasn't missed a beat in 10 years.

If I had to guess, it is probably a 12 volt unit, because I bought it at a FLAPS.
 
cas3 said:
6volt Ford relay has been working fine for years on 12 volts for me. Be sure to mount it with the button on the bottom so gravity helps to breaks the circuit or they sometimes stick on
Click to expand...

This makes sense to me. 12v requires less current/amperage, so the 6v solenoid would be overkill, but work as normal.

The small terminal in the middle of the solenoid is for the starter button on the dash.

Do you have a wiring diagram? They are pretty simple, you can use them as a reference to trace where wires run to/from.

Van Pelt has good online diagrams. But I’d rely on your Rhode Island kit diagrams. You should have a wire from the main harness going to the ignition (on/off) switch. That wire runs from the starter solenoid battery side.
http://www.vanpeltsales.com/FH_web/flathead_drawings_electrical.htm
 
Just to make sure everyone understands, the smaller terminal on a Ford solenoid is "hot" and the solenoid is activated by grounding it with the starter button.
 
Thanks y’all. Please see this photo (terrible drawing) of my wiring plan. Is this correct to get the engine started (not planning to drive it yet)? What is missing or would you change?

Again, I’m just trying to wire a temp startup stand, not the whole car yet.

1358E859-DEC9-4D8D-8784-867A2B31AF92.jpg
 
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I’m not following what your coil and dist wiring is. Your coil neg terminal will prob want a ground. Don’t know of a neg terminal on the dist. The coil will connect to your dist by the spark plug type wire. What coil and dist are you using?
 
Gotcha. If you wire the ignition according to the Stromberg instructions, the rest of the diagram looks good to me.

Some people here have a personal grudge against every electronic ignition, but they work fine if you want to use one and wire it up as instructed.
 
Thanks fritz. I used to be so against anything other than stock on any old car until I started trying some various “upgrades” and most I’ve been very happy with. Electronic ignition made my life so much easier on a past car after years of refusing to try it. I’m now a Convert and will ignore the criticism. If it doesn’t work…:::sigh::: I’ll go back to stock. Pretty simple really.
 
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