New member here, and new to the 8N world. I've been lurking and learning from the forum (thank you!) but this is my first post. I grew up on a farm, and restoring cars is a hobby that I enjoy, so I'm somewhat familiar with mechanical and electrical things, but I'm not an expert by any means.
I am helping a friend with a 12 volt conversion on a 1951 8N. The safety starter button was bypassed by a previous owner, and when we did the conversion, we also bypassed it. There is a starter button in the dash now. What we have now is a 12 volt, negative ground system instead of the original 6v positive ground. We installed a new 12 volt coil and new 12 volt lights. We ran all new wiring because the old wires were crispy and looked like a rat's nest. We cleaned the spark plugs, adjusted the gaps and adjusted the point gap.
We also had to install a new three post starter solenoid because the threads on the battery side were shot and the nut wouldn't get tight. The small post on the new solenoid is being supplied with positive 12 volts from the starter button, which is on the dash (not the original safety switch).
Everything works as it should and the tractor starts up easily. But I'm concerned that the safety starter switch is not being used. The safety switch is still in place by the shifter, but it is not wired in our new circuit. Instead, our aftermarket two pole key switch provides 12 volts to a starter button installed in the dash. The starter button then sends 12 volts to the solenoid when pressed, and the tractor starts fine.
I can't quite figure out what to do to put the safety switch back into the starting circuit. The old system was positive ground, so if we run our 12v positive wire to the safety switch and push the button, it's going to send the current to ground and bad things will happen.
Here is what I think we need to do, please feel free to correct me or confirm:
I think we need a 4 post solenoid. In my mind, a positive wire would run from the key switch to the small positive solenoid post. A ground wire would run from the other small solenoid post to the safety switch, so that when the safety switch is pressed, it would complete the negative circuit to ground, and the starter would spin. I know very little about solenoids, so I want to be sure I buy the right one, if such a thing exists for what we need to do. The starter itself is grounded to the engine block, so in my mind the small ground post would have to be isolated ONLY to the circuit inside the solenoid. I'm sure they make such a thing, but any guidance would help. Maybe there is a simpler way?
If you know of a specific link to the solenoid we need, please let me know. Thanks in advance!
I am helping a friend with a 12 volt conversion on a 1951 8N. The safety starter button was bypassed by a previous owner, and when we did the conversion, we also bypassed it. There is a starter button in the dash now. What we have now is a 12 volt, negative ground system instead of the original 6v positive ground. We installed a new 12 volt coil and new 12 volt lights. We ran all new wiring because the old wires were crispy and looked like a rat's nest. We cleaned the spark plugs, adjusted the gaps and adjusted the point gap.
We also had to install a new three post starter solenoid because the threads on the battery side were shot and the nut wouldn't get tight. The small post on the new solenoid is being supplied with positive 12 volts from the starter button, which is on the dash (not the original safety switch).
Everything works as it should and the tractor starts up easily. But I'm concerned that the safety starter switch is not being used. The safety switch is still in place by the shifter, but it is not wired in our new circuit. Instead, our aftermarket two pole key switch provides 12 volts to a starter button installed in the dash. The starter button then sends 12 volts to the solenoid when pressed, and the tractor starts fine.
I can't quite figure out what to do to put the safety switch back into the starting circuit. The old system was positive ground, so if we run our 12v positive wire to the safety switch and push the button, it's going to send the current to ground and bad things will happen.
Here is what I think we need to do, please feel free to correct me or confirm:
I think we need a 4 post solenoid. In my mind, a positive wire would run from the key switch to the small positive solenoid post. A ground wire would run from the other small solenoid post to the safety switch, so that when the safety switch is pressed, it would complete the negative circuit to ground, and the starter would spin. I know very little about solenoids, so I want to be sure I buy the right one, if such a thing exists for what we need to do. The starter itself is grounded to the engine block, so in my mind the small ground post would have to be isolated ONLY to the circuit inside the solenoid. I'm sure they make such a thing, but any guidance would help. Maybe there is a simpler way?
If you know of a specific link to the solenoid we need, please let me know. Thanks in advance!
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