New Juice.. need help on wiring.

Go a Google or other search on beavco.

This is what I got...
http://www.fullsizebronco.com/forum/showthread.php?t=632

Post what you got for installation instructions. Maybe we can collectively figure it out.

If only someone in here had a nice write-up on the wiring upgrade.








































Jrichker will be in shortly with the alternator wiring upgrade lists.

TYpically there are 3 wires.
One is a 4 gauge fused power feed to the battery side of the starter solenoid. The fuse would be 125 amps
The second wire is 18 gauge wire for voltage sense that connects to the power feed wire.
The third wire is 18 gauge wire with 12 volts from the Run side of the ignition switch. It turns the voltage regulator on.

The secondary power ground is between the back of the intake manifold and the driver's side firewall. It is often missing or loose. It supplies ground for the alternator, A/C compressor clutch and other electrical accessories such as the gauges. Any car that has a 3G alternator or other high current alternator needs a 4 gauge ground wire running from the block to the chassis ground where the battery pigtail ground connects.

Wiring parts & sources:

See WWW.partsexpress.com for the fuse & fuse holder.
Fuse @ $3.90 each (need one) http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=071-952

Fuseholder @ $5.80 each (need one) http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=263-630

4 gauge black wire @ $1.25 a foot (use string to lay out routing & determine length) http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=100-196

4 gauge red wire @ $1.25 a foot (use string to lay out routing & determine length) http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=100-194

4 gauge ring crimp terminals (package of 5) $3.25. http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=095-584

3/4 “ Black heat shrink tubing, 4ft length, $3.39
http://www.partsexpress.com/pe/pshow...number=082-058

3/4 “ Red heat shrink tubing, 4ft length, $3.39
http://www.partsexpress.com/pe/pshow...number=082-064

The new PA Performance 2G replacement alternators are designed the same way. http://www.pa-performance.com/display.asp?sku=157.

Their site states:

Note: Due to Ford TSB's and Inherent problems with the push on molded plug design all new alternators use stud or post connections to reduce the risk of heat build up and fire associated with the Original design. The three wires on the OEM plug will need to be cut off and provided terminals crimped and soldered.

The alt must be designed so that the Orange/Black wires from the large connector are tied together on one post while the stator wire is connected to the other post.

Do any of the original Mustang wiring connectors look like they fit on the new alternator?

mustangillusion said:

Yes actually the other plug (smaller one) looks like it would plug right In (i havnet tried). But the larger one has the two posts as shown in the picture. Wouldnt I still need to upgrade the wiring to run 120amps? I think I would want to, just to be safe.

Click to expand...

You will definitely need to upgrade the wiring, See my previous post for wiring parts and sources.

Do not connect the black/ orange wires to the new alternator.

Look at the plug on your car that seems to fit the new alternator. What color wires are on that plug?

If that is true, then this won't be difficult.

Disconnect the battery power ground by removing the negative battery terminal.

One 4 gauge wire goes from the big stud on the alternator to one side of a 125 amp fuse. The other side of the fuse goes to the battery side of the starter solenoid. Pre-fab 4 gauge cables with lugs already on the ends are available in most auto parts stores. Look for the starter switch to starter cables. The fuse & fuse holder may also be there too.

The power feed plug for the old alternator has two black/orange wires and one small white/black wire. After you are finished working with the white/black wire, tape the plug up good and secure it out of the way.

The white/black stator wire gets the insulation stripped back about 1 1/2" in the middle of the wire & cut in the middle of the stripped area. Then a short length of white wire with a ring terminal gets spliced on to the white/black wire. Slide on enough 1/4" heat shrink tubing on the white wire to cover the solder splice you are going to make. Next all 3 wires get soldered together & the heat shrink tubing gets shrunk. When you finish, the white/black wire looks like a "Y" with 1 white arm and 1 white/black arm. Connect the ring terminal to the small stud on the alternator.

Plug the 3 wire plug into the mating connector on the new alternator.


Add a 4 gauge ground wire running from the block to the chassis ground where the battery pigtail ground connects.

Re-connect the battery negative terminal and you are done.

This arrangement retains the stock wiring so if your new alternator ever fails, a stock 65 amp alternator can be swapped in without any problems.

mustangillusion said:

Sounds easy enough but just to make sure im understanding clearly let me ask a few questions. On the stator wire could you not just use one of this splice lock deals and run that wire up to the stator post. Im finding it difficult to figure out why you would cut the original startor wire instead of just stripping it and adding the new wire?

Click to expand...

The idea is that you end up with a "Y" wire for the stator. The old plug still has all the wires connected to it and the new wire has the ring terminal crimped on it. That way the old alternator still works with no changes. If your new high current alternator is DOA or dies at a later date, it is very easy to put the old alternator back in place.

Solder and heat shrinking the splice makes sure that you have quality connections and no intermittent connections that will drive you crazy. Under the hood is a hostile environment that demands the best connections you can make.

When upgrading to the heavy gauge power cable I would also consider routing/supporting the cable so there is no undue stress on the post. The post does not look quite as stout as those found on a 3G alt and going by the pics it looks like it would be more susceptible to damage from cable weight/vibration especially since the post will be close to the 8-9 o'clock position when the alt is mounted.

mustangillusion said:

I thought of another question I had. What do I do with the third wire on the alternator? Other than the plug into the voltage regulator does the alternator only require two wires? (meaning the upgraded power wire and a stator.) Im just asking because in stock for the alt has 3 wires on the large plug?

Click to expand...

On the stock large plug there are two Orange/Black wires and one White. Both O/BK wires are tied together further up the cable so in essence it is a single wire.