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Author Topic:   Under hood Power Source?
JAAZZY
Gearhead

Posts: 691
From: Bay Area, CA
Registered: Apr 2001

posted 09-24-2001 02:43 PM     Click Here to See the Profile for JAAZZY     Edit/Delete Message   Reply w/Quote
I am ignorant about a lot of things but electrical is probably at the top of the list. I was hoping to find an easy 12v source under the hood of my 65. I was wondering if I couldn't just run the wiring to the starter solenoid? If I run it to the same side that the battery + side connects to would that give me power only with the key on? Thanks.

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DaveK
Gearhead

Posts: 171
From: Sterling, VA
Registered: Dec 99

posted 09-24-2001 04:39 PM     Click Here to See the Profile for DaveK   Click Here to Email DaveK     Edit/Delete Message   Reply w/Quote
If you run a wire to where the battery connects, you'll have +12V all the time. I think you need to take it from the 'I' post of the solenoid.

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JAAZZY
Gearhead

Posts: 691
From: Bay Area, CA
Registered: Apr 2001

posted 09-24-2001 05:55 PM     Click Here to See the Profile for JAAZZY     Edit/Delete Message   Reply w/Quote
Thanks... I am wondering if I can run my electric fans from there so I don't forget and leave them on like I have done before. They take a lot of juice and wear the battery down in no time.

Does everyone agree?


quote:
Originally posted by DaveK:
If you run a wire to where the battery connects, you'll have +12V all the time. I think you need to take it from the 'I' post of the solenoid.

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steve'66
Gearhead

Posts: 4085
From: Sonoma,CA,USA
Registered: Mar 2000

posted 09-24-2001 06:31 PM     Click Here to See the Profile for steve'66   Click Here to Email steve'66     Edit/Delete Message   Reply w/Quote
Jas,

I added a 30 amp relay ($5) next to the solenoid. Wire the 'I' post to the coil of the relay and ground the other coil wire, and the +12v battery post through the relay's contacts. The relay will energize whenever the key is on, and the hi-amperage will flow from the +12v post on the solenoid.

SteveW

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JAAZZY
Gearhead

Posts: 691
From: Bay Area, CA
Registered: Apr 2001

posted 09-24-2001 06:57 PM     Click Here to See the Profile for JAAZZY     Edit/Delete Message   Reply w/Quote
Steve,

I understand in theory but maybe it is because I don't understand what the relay looks like. I wire the "I" to the relay. What other coil wire do I ground? Then I run a jumper from the solenoid to the relay?

Somehow I think I have it all wrong. I really am behind on the electrical connections but am trying to learn it. If you can explain it again maybe I'll figure it out. Would I be able to run the fuel injection from here as well? Lastly, where do I buy it? Thanks.

- Jas

quote:
Originally posted by steve'66:
Jas,

I added a 30 amp relay ($5) next to the solenoid. Wire the 'I' post to the coil of the relay and ground the other coil wire, and the +12v battery post through the relay's contacts. The relay will energize whenever the key is on, and the hi-amperage will flow from the +12v post on the solenoid.

SteveW


[This message has been edited by JAAZZY (edited 09-24-2001).]

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JAAZZY
Gearhead

Posts: 691
From: Bay Area, CA
Registered: Apr 2001

posted 09-24-2001 08:01 PM     Click Here to See the Profile for JAAZZY     Edit/Delete Message   Reply w/Quote
I found a little info on the net. I think I understand it a little better. "I" terminal is just to activate the coil to let the power from the battery flow. Sound right?

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franklin
Gearhead

Posts: 128
From: VA
Registered: Nov 2000

posted 09-24-2001 11:28 PM     Click Here to See the Profile for franklin     Edit/Delete Message   Reply w/Quote
The "I" terminal wire is the same wire as the "bat" wire on the ignition coil. The "bat" wire on the coil as you probably know makes the spark for the engine so it is hot anytime the key is on. But, this is not a true 12 volt coming from the keyswitch. It runs through a resistor or resistor wire which keeps approx 9 volt on the coil while running. Think of the "I" terminal as a "back door" or officially it is known as a bypass wire. It puts a full 12 volt on the "bat" of the coil during cranking only to make the car start easier. It may work, but is really not the proper place for a hot in run 12v source. It definitely will not be able to handle any load, since more load means more voltage drop across the resistor. The relay idea may work, but you still don't have a full 12volt running it. I would run a small wire from the acc or ign part of the fuse box to trigger the relay, and run heavy wires from the solenoid/battery connection to the contacts of the relay.

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steve'66
Gearhead

Posts: 4085
From: Sonoma,CA,USA
Registered: Mar 2000

posted 09-25-2001 10:42 AM     Click Here to See the Profile for steve'66   Click Here to Email steve'66     Edit/Delete Message   Reply w/Quote
Jas,

Franklin is right, but the 'I' terminal works fine and is "clean" (no wires running from the dash). The relay I used was for auxillary lights. I got it off the shelf of an auto parts store by the fog lights. If you want to run other stuff too, just make sure the relay's amperage rating is sufficient to handle everything. If you still need help, e-mail me a fax # and I'll fax you a diagram.

SteveW

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JAAZZY
Gearhead

Posts: 691
From: Bay Area, CA
Registered: Apr 2001

posted 09-26-2001 01:29 AM     Click Here to See the Profile for JAAZZY     Edit/Delete Message   Reply w/Quote
Thanks Steve I'll let you know.

I spent halfd the day re-wiring under the hood since I burned quite a bit of wire when the system shorted this weekend. Looks good but I don't know if it works yet since the battery is dead.

quote:
Originally posted by steve'66:
Jas,

Franklin is right, but the 'I' terminal works fine and is "clean" (no wires running from the dash). The relay I used was for auxillary lights. I got it off the shelf of an auto parts store by the fog lights. If you want to run other stuff too, just make sure the relay's amperage rating is sufficient to handle everything. If you still need help, e-mail me a fax # and I'll fax you a diagram.

SteveW


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