4g alternator wiring concerns

[Teal68]

I am getting my 2001 explorer serpentine set up with 4g alternator going and it seems I have read it can be a fire hazard.

Question 1: Maybe something to do with the ammeter???? I'm not finding clear info if it's a problem or not.

Question 2: Can I just simply unplug the old regulator once the 4g is wired up?

Thanks,
Tyler

 

[DirtDonk]

The 4G is not a fire hazard in and of itself.
The 2G was, due to it's use of under-sized wire and not-too-weatherproof connectors that built up resistance.

The ammeter is not a fire hazard because you can no longer use it with a modern alternator. The feed wire from the original alternator is 10ga and you need at least 6ga cable.

You will need to add a new charge wire complete. Directly from the alternator's BAT output post to the starter relay and positive battery cable.

Yes, the old regulator goes bye-bye because the new alternator has it's own regulator internally.
So all of the old stuff is gone, but most people re-use the Green w/red switched power wire from the old regulator to feed the same color wire on the new alternator's regulator plug.

Paul

 

[DirtDonk]

Here's the main idea for your new charge cable: https://www.wildhorses4x4.com/product/Battery_Charge_Cable_AMG_fused/Bronco_Starters

For generally a short run between the alternator and starter relay, this size cable is a bit of overkill. But if the bean-counters at Ford said that overkill is worth the extra cost, then most of us think it's a good idea to follow.
On the longer runs of cable in vans and pickups, Ford actually uses the larger 4ga cable, but for these shorter runs, 6ga is more than sufficient.
Just make sure to keep the connections clean and tight.

A standard 3G rated at a conservative 130a is generally capable of 140a or even more sometimes. Standard rebuilds often test out at up to 150a output.
Hence the need for larger wire.

Plenty of 3G/4G install threads around here to give you the full rundown on the steps needed to make a safe and clean install. Mostly about what to do with the old wires.
Remember that the old Black w/yellow charge wire is directly connected to the battery, so just disconnecting it from the alternator does NOT render it safe to just leave hanging around.
You either need to re-purpose it for other duties, or safely cap it off so it can never touch anything.

Paul

 

[Crush]

I re-used the pos and neg explorer wires from the batt to the starter/alternator, the relay and the neg to the grounds. there were two or three ground connections in that harness, wires for the red/green to hook to and go to the alt. i then just hooked the old blk/yellow wire(power loop) on both ends to the solenoid relay so it is a loop. no exposed ends anywhere. I plan on using the end that went to the old alt to hook a power distribution box to..

 

[Teal68]

Thanks for the info Paul and Chuck. Very helpful!
Tyler