switched power in run and start

[wesleydax]

where can i get switched power that is hot in run and start position? the only one i know of is coil + but the efi kit says not to hook it there.

 

[Viperwolf1]

Green-red wire from the old voltage regulator.

 

[wesleydax]

Thank you. Would not have found that.

 

[Broncobowsher]

Green-red wire from the old voltage regulator.

You need to back that up with a diode to provide power in start as well. That wire off the regulator is not a reliable power source during crank. Depends on the ignition switch. From the factory start power comes off of the "I" post of the solenoid. Anything else being powered didn't matter, all they were concerend with powering during start was the starter and ignition.

 

[lonesouth]

Old post, but i figured someone may some day benefit. I think this would provide reliable 12V in start and run. using a relay instead of a diode. Advantage being that you can get more amperage than a diode setup would allow(restricted by the factory wire size).

This uses the green w/red stripe wire that comes off of the voltage regulator as the trigger. In start, the green/red does not get any voltage, and the coil is in the open state with pin 87 getting power from pin 87a which is connected to the I terminal of the starter solenoid. When the key is released and changed to a run state, the green/red gets 12V, closing the relay and powering 87 from pin 30 connected to B+.

 

[Viperwolf1]

Old post, but i figured someone may some day benefit. I think this would provide reliable 12V in start and run. using a relay instead of a diode. Advantage being that you can get more amperage than a diode setup would allow(restricted by the factory wire size).

This uses the green w/red stripe wire that comes off of the voltage regulator as the trigger. In start, the green/red does not get any voltage, and the coil is in the open state with pin 87 getting power from pin 87a which is connected to the I terminal of the starter solenoid. When the key is released and changed to a run state, the green/red gets 12V, closing the relay and powering 87 from pin 30 connected to B+.

How do you expect to turn the engine off with that setup?

Green-red wire SHOULD be hot in start and run in '67-'77. This is true because it is used to test the brake warning bulb in start and turn the regulator on in run. If you want more current run your relay without the "I" wire.

 

[lonesouth]

After reading too many threads, I was under the impression that red/green was unreliable for start.

 

[Viperwolf1]

After reading too many threads, I was under the impression that red/green was unreliable for start.

It would be an ignition switch problem if it was unreliable.

 

[lonesouth]

that makes it much simpler then

thanks!

 

[brianstrange]

..... or you could trace the resistance wire back to the IGN sw, and power it from there

 

[Steve83]

Any circuit connected to the ig.sw. "I" terminal. The coil runs at reduced voltage because of the resistor - that's why you can't use it, but you can overlay a wire directly back to the ig.sw.



If you need more current than the ig.sw. can pass, use a relay triggered by the "I" terminal, and supplied through an appropriately-sized fuse (near the starter relay) & wires.

 

[lonesouth]

Again, I was under the impression that the I was internally switched by the starter solenoid and it was open when the starter was disengaged.

 

[brianstrange]

Again, I was under the impression that the I was internally switched by the starter solenoid and it was open when the starter was disengaged.

This is correct! The "I" terminal offers a full 12 volts from the solenoid to the coil during start. It bypasses the resistance wire. The post will also read a reduced voltage while running, only because it's then being back fed by the coil.

 

[Viperwolf1]

Again, I was under the impression that the I was internally switched by the starter solenoid and it was open when the starter was disengaged.

That is true if there is nothing else attached to "I". The factory wiring has the ignition resistor bypass wire (brown wire) attached there. Your relay will send battery voltage to that wire when the ignition switch is turned off and the green-red wire disengages the relay. Thus, your engine would continue to run with the key off.

 

[Steve83]

Again, I was under the impression that the I was internally switched by the starter solenoid....

You appear to be replying to my statement about the ig.sw. "I" terminal, but you're replying about the starter relay "I" terminal. They're different, and do different things. Don't confuse them just because they have the same label.

 

[lonesouth]

That clears things up Steve.