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Discussion Starter #1
I've got another one for the day, I'm out of practice.

I'e been running a smaller gear reduction starter from an SN95 I believe for years now, but I always left the apron solenoid. So I have constant power into the side of the solenoid, then OUT of the solenoid, to the mini starter.

I then have the trigger wire for the starter going off the other side of the fenderwell solenoid. So in essence, the main larger apron solenoid is being used as a relay, to trigger the relay/solenoid on the mini starter.

Now I can't recall, but I probably did it this way out of laziness or a time constraint. but searching, it appears everyone is wiring it that way (?!).

I'd like to eliminate the fender apron solenoid to clean up my wiring. So I would just have the main power wire from the battery, to the starter, and then the trigger wire going to the mini starter solenoid.

Any issues??

Thanks!
 

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No, but you probably want to use a small relay under the dash to take the load off of the ignition switch.
 

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What about the main power wire to the dash? That also comes off the solenoid. You will at least need a power distribution block.
 

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Discussion Starter #4
Oh no, nothing stock left of my wiring,so no worries about the rest of the car (main power I mean)

Matter: Do you know the draw of the mini-starter solenoid? Or the fender mount solenoid? And is it more than the keyswitch maximum? (Do we know the keyswitch maximum?)

Thanks!
 

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The solenoid is a relay. A relay uses low power to activate a coil that closes a large switch for a heavy load. The solenoid/relay itself uses very little power. So there is no need to add a relay under the dash as that is the solenoid's job.
As mentioned, you will need an electrical junction block. You can use the large stud on the starter's solenoid for that purpose but now you have a bunch of wires running down to the starter. It is much easier to leave the fender solenoid in place and use it as the junction block.
 

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I once tried using a Bosch type 30 amp relay in place of the fender mounted solenoid, it lasted about 3 days before it wouldn't do anything. So I have to assume that the trigger current is greater than 30 Amps. Amazon sells a 75A relay if you want to try it. It has the same pin outs as the 30A relay, it just looks different.
 

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I copied the SN95 system and used a relay with a diode built into it. Pulled the relay from a ford power panel. Still working 5 years later.
Awhtx is correct, the original dash wiring is only used for a signal.
 

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Discussion Starter #8
Thanks guys. No, I am very familiar with the electrical, I am wondering if anyone knows the amp draw.. (or I can measure when I do this if anyone else is curious I guess). I will be using the battery terminals as junction blocks as I have run everything to that location.
I was hoping someone knew the amp draw on the solenoid of a mini starter/gear reduction starter, or more importantly, the max draw the keyswitch can handle. (My solenoid trigger wire is running directly to the keyswitch).
 

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As a signal wire to a relay, the amp draw is minimal. You can't run it direct to the starter.
 

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Discussion Starter #11
289, what do you mean? And please think >SN95 here. Not sure what you mean by direct to starter? Starting in 1994 (If I recall, off the top of my head), the Solenoid is on the starter. There is no longer an apron solenoid.
Does anyone have the maximum current of a 67/68 starter switch, Crank signal?

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Heavy battery cable to starter, original S terminal wire as trigger/signal into relay, ground out the other side, fused power in, output to starter.
 

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I'd use something like this with at least 4 relay positions to take away the clutter at the battery terminal. Need at least 4 for high beam, low beam, horn, starter. Plenty of choices available.
 

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I would drop in a 40amp 5 pin spdt Bosch style relay. That should be overkill and they are robust and easy to come by.
 

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Hard to read the diagram on that relay. It needs a relay with a diode in it to kill the voltage spike a PMGR starter produces. It can cause the starter to continue spinning when you release the key.
The starter can create voltage like an alternator.
 

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289vert
The 80amp relays don’t have diodes. I picked up that box couple of years ago.
 
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