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Starter solenoid/ starter wiring question

Waverous

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Need some advice. I am rewiring my Bronco using new wiring and I am down to confirming power from the key to the starter. Here is what I have:
  • “Kwick Wire” loom
  • Mini Starter
  • 3g Alternator
  • Stock starter solenoid
So far, I have a battery cable coming from the battery to the solenoid lug post (“S” post side of the solenoid) as well as a starter cable from the same post to the mini starter. I have the wire from the coil to the “S” post of the solenoid and I have a wire from the cable lug on the “I” side of the solenoid to the post on the mini starter.

I am trying to confirm I have power running through the starting system without cranking the engine yet. So far, I have:
  • 12 volts from the battery to the “S” side lug
  • 12 volts from the coil to the “S” post on the solenoid when key is turned
  • 12 volts from the “S” side battery lug to the starter
  • 0 volts from “I” side lug to the mini starter post when the key is turned
It seems to me that there should be some discernible electrical flow from the “I” side lug to the mini starter – correct?
 

Jdgephar

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mini-starter-wiring.jpg


The main difference with the mini starter is that the "I" side lug goes to the small tab that actuates the bendix on the starter. "S" side lug uses a heavy guage wire to the bendix lug.

Seems like what you described is correct. The mounting bracket is the ground for the coil of the solenoid. Make sure thats a solid ground connection, and not insulated by paint or something.

Sent from my SM-G981U using Tapatalk
 
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ngsd

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Also some of the new torque starter such as MSD have a built in solenoid.
 

DirtDonk

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Here is what I have:
  • “Kwick Wire” loom
  • Mini Starter
  • 3g Alternator
  • Stock starter solenoid
So this means that the START wire on the "S" post should be Purple/Violet. Correct?

So far, I have a battery cable coming from the battery to the solenoid lug post (“S” post side of the solenoid) as well as a starter cable from the same post to the mini starter.
Sounds correct so far.

I have the wire from the coil to the “S” post of the solenoid and I have a wire from the cable lug on the “I” side of the solenoid to the post on the mini starter.
Not sure about this. Some of it sounds bass-ackwards.
The only wire (normally) that should be on the small S post of the fender mounted relay/solenoid should be the Purple START wire from the ignition switch. Or from the NSS if you have an automatic?

The "I" wire going to the starter solenoid on the other hand sounds correct.
Will you be utilizing the small "I" post for ignition duties or anything like that? That's where your wire from the coil should go. If you have a wire from the ignition coil to the "S" post it will crank the starter every time you turn the key to the ON position.

I am trying to confirm I have power running through the starting system without cranking the engine yet.
Then you better remove the "S" wire or disconnect one of the wires from the starter!
Sounds like it's fully connected, and if so you're going to get the starter to crank when you turn the key. Best to have a helper, but if not you can verify power to different places in other ways. Perhaps a test lamp you can see from the front seat?

So far, I have:
  • 12 volts from the battery to the “S” side lug
  • 12 volts from the coil to the “S” post on the solenoid when key is turned
  • 12 volts from the “S” side battery lug to the starter
  • 0 volts from “I” side lug to the mini starter post when the key is turned
It seems to me that there should be some discernible electrical flow from the “I” side lug to the mini starter – correct?
Correct. If you are getting 12v to the S post then the starter relay should be energized and close the contacts.
As mentioned, verify that the starter relay on the fender is getting a good ground through it's mounting ears. A quick way to tell short of removing it and scraping paint, would be to run a dedicated ground wire from the battery to the mounting bolt. This is often where we put the main body ground anyway, when re-wiring a Bronco. Originally it was on the inner wheel well near the exhaust manifold, but when going with aftermarket battery cables a new one is usually easier/cleaner/shorter to connect to the body near the relay/solenoid.

Try that and see what happens. But if you keep the wire from the ignition on the S post be ready for the starter to crank when you turn the key to ON.
If it does not crank, you may have a defective starter relay. But those are easy and quick to test right in place. Just use a jumper wire or tool to connect your battery side to the small S post. If you hear it click and the starter cranks you know where to go from there.

Paul
 
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Waverous

Waverous

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Sorry for the delayed reply DirtDonk (out of town).
I found the purple wire from the NSS which was left (by me) tucked securely in the wire loom and forgotten :rolleyes:. I have it now hooked to the "S" post but I haven't tested it yet due to lack of time - I will do it tomorrow

BTW - I am running a manual trany
 

DirtDonk

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Great news. Can’t wait to hear the testing results.
Crossing fingers…
 
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Waverous

Waverous

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OK race fans -
Now that I "found" the purple wire (this is what happens when you're old and the mind goes; allowing months to go by between working on the bronco and forgetting where you left off; ignoring the installation manual) and installing on the "S" post, I get 12v on the "I" post and on the "I" side lug to the starter - volts present with the key "on" and cut out when ignition key turned to "crank".
 

ngsd

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sounds like the switch wiring is backwards
 

DirtDonk

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What color wire is connected to the “I” side of the fender mounted relay, and what color wire is on the “I” side of the starter solenoid?
And where did they go? What kind of writing is on them.
 
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Waverous

Waverous

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OK, I went back and looked at the switch wiring and I have this:
- Red/blue wire running to the "S" post
- Red/green wire running to the coil directly (no resistor wire or ballast present)

With power coming from the key to the coil directly, do I need to run a connection from the coil to the "I" post?
 
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Waverous

Waverous

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Yes, I have - the problem is using an aftermarket wire harness and their directions, having a G3 alternator, using a high torque mini starter, and AC - it just takes a while to connect the dots (so to speak). Some of those dots aren't very clear and I want to tap the brains of the true gurus here.
 

ngsd

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One thing you can do is meter the leads at the switch. If the lead going to the solenoid is hot when at run and cranking there you will know if it is between that and the solenoid or after.
 

chrlsful

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Chad said: "...an 'electron dummy')...."
I aint alone,
BTW: schematics just confuse me. Only thing
makes sense is the colored lines & followin them.
 

ngsd

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So if I am following along, you have a 3g alternator and new wiring, you eliminated the voltage regulator as it is internal correct? You have the green wire back on harness to green off the alternator, yellow to battery, start wire probably purple to the S side of the solenoid and using a mini starter. You don't have voltage at crank position on the purple wire or was I mistaken? One thing that was mentioned above is that some starters such as the MSD need to see the start wire at the starter instead of the solenoid. Here is my build using the same as you have. I have jumped the S post to the starter solenoid. (msd starter)
 

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Waverous

Waverous

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Am I following you correctly - red/blue ignition wire to S post and then onto the mini starter solenoid? Oh and correct regarding purple wire-no power at crank
 

ngsd

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No, are you using the Centech harness? The Purple wire should be hot at crank. if not, that could be the issue. The centech probably came with an aftemarket switch and an adapter to use with a stock switch. Are you using a stock switch or after market generic? still shoud have power at purple though I would think.
 
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