73 Solenoid/Starter voltage issue

[MNMustang73]

I need help figuring out why I have no voltage coming out of the solenoid and going to the starter.  I have 12 volts from the battery post to the solenoid, 12 volts on the "S" terminal and 12 volts on the "I" terminal with the key turned forward but I have no voltage going to the starter.  I discovered that if I touch a cable from the negative post from the battery to the "S" terminal on the solenoid with the key turned forward the starter cranks and the car starts.    

Both the battery and the solenoid are new, so I have no idea what the issue is at this point? 

Any advise or ideas would be appreciated.

 

[Canted 393]

It sounds like your new solenoid is crap, a lot of junk ones out on the market today.

Try these I have had good luck with them and their US made.

https://www.jegs.com/i/Accel/110/40200/10002/-1

 

[Hemikiller]

If you apply 12V from the positive post to the "S" terminal, it should close and engage the starter. If it won't do that, you have a bad solenoid. As Canted states, get a good solenoid. Try to get the linked Accel, or a NAPA Echlin, Standard or Motorcraft unit. The cheapies sold by Advance/Pep Boys/Oreilly/Autozone will get you going for about $8, but probably won't last very long.

If there's anything that drives me nuts about the current state of the automotive parts business, is that the chains are pawning their cheap crap at the same prices as the good stuff from the small stores they drove out of business.

 

[SteveO_71]

I'm still trying to understand how the engine cranks when a ground is applied to the S terminal. As mentioned, typically +12 is applied there to activate the solenoid and crank the starter.

 

[delawarebill]

ok first there are no negative posts on that sol.

looking at sol the front lg is from bat, the other lg is starter, the S is 12v from ign sw telling the sol to engage and I is to the dizzy . the I post is a temp 12v to dizzy when car starts it goes to the resistor wire to dizzy. so u putting a Neg wire anywhere on that sol is a no no.. the only neg on that sol is the screws that mount to fender well for ground.

get a new solenoid.

but do this test, ign on 12v or less at dizzy through resistor wire, ign to start u will have 12v to the S wire and only in the start, hook S wire up to sol and hit sw again and now read the I terminal, not the wire coming off it. (disconnect it then read terminal)

 

[MNMustang73]

If you apply 12V from the positive post to the "S" terminal, it should close and engage the starter. If it won't do that, you have a bad solenoid. As Canted states, get a good solenoid. Try to get the linked Accel, or a NAPA Echlin, Standard or Motorcraft unit. The cheapies sold by Advance/Pep Boys/Oreilly/Autozone will get you going for about $8, but probably won't last very long.

If there's anything that drives me nuts about the current state of the automotive parts business, is that the chains are pawning their cheap crap at the same prices as the good stuff from the small stores they drove out of business.

I mis-spoke in my first email.  I do not have 12v at the "S" post even with the key turned forward.  The solenoid is the best that NAPA carries????  Do you think I have grounding issue.  I will take my solenoid to NAPA and see if they can test it.

Just so you know I have just put the engine back in and while I think I have everything connected right (it matches both pics and the wiring schematic) I may be missing something?  It still pretty bare bones with no neutral safety switch or wiring connected inside the car.  Even so, I still cant understand why the solenoid gets voltage but it will not put any voltage out?

 

[MNMustang73]

ok first there are no negative posts on that sol.

looking at sol the front lg is from bat, the other lg is starter, the S is 12v from ign sw telling the sol to engage and I is to the dizzy . the I post is a temp 12v to dizzy when car starts it goes to the resistor wire to dizzy. so u putting a Neg wire anywhere on that sol is a no no.. the only neg on that sol is the screws that mount to fender well for ground.

get a new solenoid.

but do this test, ign on 12v or less at dizzy through resistor wire, ign to start u will have 12v to the S wire and only in the start, hook S wire up to sol and hit sw again and now read the I terminal, not the wire coming off it. (disconnect it then read terminal)

I mis-spoke in my first email.  I do not have 12v at the "S" post even with the key turned forward.  The solenoid is the best that NAPA carries????  Do you think I have grounding issue.  I am perplexed why going to ground worked as well and I am fairly confident that I have it wired correctly.  I did touch a cable from the battery to the "S" post with the key turned and it did engage the starter.  I will take my solenoid to NAPA and see if they can test it.

Just so you know I have just put the engine back in and while I think I have everything connected right (it matches both pics and the wiring schematic) I may be missing something?  It still pretty bare bones with no neutral safety switch or wiring connected inside the car.  Even so, I still cant understand why the solenoid gets voltage but it will not put any voltage out?

 

[Hemikiller]

Just so you know I have just put the engine back in and while I think I have everything connected right (it matches both pics and the wiring schematic) I may be missing something?  It still pretty bare bones with no neutral safety switch or wiring connected inside the car.  Even so, I still cant understand why the solenoid gets voltage but it will not put any voltage out?

You will not get 12V out to the solenoid if you don't have the neutral safety switch hooked up and adjusted properly. 

If you gave it 12V from battery to the S terminal and it engaged the starter, the solenoid is working properly.

 

[delawarebill]

so with ign on u do not have 12v ON the S wire. that's ok for now, but troubleshooting later. put key on, and jump off pos battery to S post and hopefully it'll start and keep running. don't leave jumper on the S post that is for start only. u can trace the 2 wires for the neu sw and just jumper them, hook up S wire to sol and hit key to start. if no starter see if u now have 12v in the start position and measure at the S wire. the first test will tell u if u have a bad sol, the second part will tell of a bad start wire or sw if no voltage

 

[Don C]

It would help all of us keep on the same page if you used the correct names for the ignition key positions. Starting with the key rotated all the way counterclockwise, the first position is Accessories, then Off/Lock, next is Run or On, and then rotated all the way clockwise is Start.

Another possibility for the continuous run problem is if your car originally had an electric choke. Ford connected the choke element to the stator terminal on the alternator so the only time it is powered is when the engine is running. If that wire was connected to the wire that runs from the "I" terminal to the coil your engine would continue to run.

After you turn the ignition switch off and the engine is still running disconnect the wire on the "I" terminal, if the engine quits it is the solenoid, if not, it's something else.

 

[MNMustang73]

Just so you know I have just put the engine back in and while I think I have everything connected right (it matches both pics and the wiring schematic) I may be missing something?  It still pretty bare bones with no neutral safety switch or wiring connected inside the car.  Even so, I still cant understand why the solenoid gets voltage but it will not put any voltage out?

You will not get 12V out to the solenoid if you don't have the neutral safety switch hooked up and adjusted properly. 

If you gave it 12V from battery to the S terminal and it engaged the starter, the solenoid is working properly.

Thanks for the input.  It was the neutral safety switch not being bypassed that was the issue.  I still have no idea why it would crank when you grounded it but it works correctly now.