...where does the small stud wire come from? I think from the picture shown earlier in this thread, that the cable from my solenoid that goes to the starter also has a smaller gauge wire and that is the one that goes to the small stud??? just doesn't make sense to me because the power is coming from the same place and hooks to two different post on the starter.
Just to make sure, can you post up a pic of your starter? This way we're certain what we're working with.
The starter wiring is actually pretty simple once you get it.
Let's start by changing some words for starters though.
For this discussion the unit on the wheel well is the "starter relay" and the unit piggybacking the starter motor is the "starter solenoid". Which, in fact, is just exactly what they are.
The starter relay simply takes the higher load of the starter solenoid off of the weaker ignition switch. Helps it last longer and, when you release the key it isolates the starter so that it does not feed back into the system causing run-on.
The starter solenoid does the duties of both a switch and the lever that pushes the gears into mesh. This "physical movement" of the lever and gear is actually what defines it as a "solenoid" in the first place. Instead of just a simple relay/switch that only closes electrical contacts but does not do any manual labor.
On the fender, the left side of your starter relay still gets the positive battery cable, and you move your starter cable from the right side to the left side. The other end still goes to the starter solenoid's large post.
This is what messes a lot of people's minds, because they think the power is always at the starter now and so it'll spin as soon as you connect the battery. This does not happen because the solenoid does not let it make an electrical connection until the small wire tells it to.
The new smaller (10ga usually) wire now connects from your starter relay's right post to the new starter solenoid's small post. This is the wire that tells the starter to spin.
When you turn the key to START, your old relay now simply tells the new solenoid to kick things into gear and get to spinning.
There is a large gauge interconnect between your starter solenoid and the motor itself. This is because both need a good current flow from the battery to work properly, but they are able to stay isolated until the small wire gets it's signal from the relay and closes the big heavy duty switch inside the solenoid.
Clear as muddy muck now?%)
Many millions of American cars and trucks used starters similar to your new one and had a heavy gauge wire (probably 10ga too) run directly from the ignition switch to the starter solenoid, without the use of the fender mounted relay. Our stock Ford setups used lighter duty switches and smaller gauge wires because the relay was necessary for our stock style starter. Wiring our switches directly to the new starter solenoids is not a good idea due to the heavier load placed on the ignition switch and the smaller wire. Even Ford retained the starter relay mounted on the fender when they switched to the smaller PMGR starters with the piggyback solenoids. We do the same for the best results.
We also have found that for some reason not found on legions of GM vehicles that eliminating the relay and losing it's isolating characteristics allowed some feedback from the spinning starter motor into the system and caused the starters to run on for a couple of seconds. Surprised a lot of people.
So we continue to use the relay and go by the diagram that Garry posted before.
It also gives you a much more convenient and heat/chemical/weather resistant location to mount extra wires and such.
Bonus.
Some of us have successfully run both the large starter cable and the smaller 10ga trigger wire from the same right side stud of the fender mounted relay. The starter doesn't care that the electricity to energize the solenoid
AND spin the starter motor arrives at the same time. But you do lose the isolating properties and might run afoul of the run on. Haven't had that happen yet, but it could.
Paul
And then you will be helping out others...