2002 f150 4.2 liter. Wanting to do the big 3 but having trouble figuring out where to connect to the alternator. Here is what the alternator looks like. Not sure which ones are positive and negative and confused as to how to connect my 0 gauge wires since the existing wires aren't bolted on so I can't just add my 0 gauge with a ring terminal to the bolt.

 

Yea, some call the entire Alt case absolute ground. I guess you could say, -very close to it since absolute ground is actually the block matting surface where the alt connects.

Also a Big 3 doesn't actually complete things, it's close. The BIG 4 is a solid complete circuit of equalized current.

The answer for you is anywhere on the alt case. There's usually an 8mm thread port on the back somewhere.

1/0 try to use tinned cast copper lugs or solid copper connectors tinned. If they are not tinned, use "No Ox ID A Special Compound" so your copper doesn't skin. Once it skins the resistance increases significantly - skin = oxidation. Vehicle voltage uses the core and very outside of the cable and surfaces for transmission.

To much to explain in one shot..Crimping is best with cable that large. If by your working with smaller cable, you can solder, but use Silver Bearing Solder.

You can get get 16T hydraulic crimpers very cheap now. If you trust Ebay, you can get them new ver cheap and surprisingly, they are built very well. 50 or 60 bucks and you can crimp anything. Great for AC Coolant and air compressor hoses.

Well hope I answered your question somewhere in there, I think I got it lol.

 

Wow lots of info there. Where is the positive lead on the alternator?

 

Wow lots of info there. So the negative on the alternator is anywhere on the casing....but where is the positive lead?

 

It would be cabled in red, this is a spare large case Ford Motorcraft 3G I rebuilt, just for sort of a reference, -



There should be a yellow zinc'ed post or threaded stem coming from the back for positive. It looks like Black /Orange is your positive with that one. I can't see it very well with your pic...how , where it connects or if you have another cable not pictured. If that's the only cable , it's hot.

 

You're a huge help! How do I go about connecting my ring termin to the black/orange cable though?

 

So your keep your Orange/Black or replacing it ? Just to be sure.

 

Keeping it. I heard its better that way

 

Yea, it can be if your unsure, but I chose to have the entire system to reach the benefit of this install. That = eliminating the existing and much more work to set up properly.

The easiest way to do what you want is to either double up on the post or purchase/make a 2 into one Y before the connection.

Regardless, you need 1/0 x 1/4" lug. Crimping is the best. I have some pics of 1/0 crimps I've made in the past, -



That's a cut away of cable and lug crimping for a solid resistance free connection. A must IF you want this set to work as it should.

 

Whew, I thought the big 3 was a simple bolt-on project, but this seems a bit more complicated.