New electrical - help

[robofig]

I stripped out every old wire in the bronco and I am starting new.

I have done quite a bit of searching with not much luck.

I'm running an explorer serp set up w/ a 4G alternator, and a mini starter.

Does someone have a diagram showing how to wire this up correctly,

what gauge wire to use between all components,

what size mega fuse to use and its location?

Also keep in mind a winch will be added in the future.

Thanks in advance.

 

[old 71]

Robofig, are you looking to use a pre made wiring harness , or make your own ?there are a lot of wiring harnesses to choose from on the market , painless, American autowire , centect, Ron Francis , ez wire to name a few. First three come with instructions not sure about Ron or ez though. If your making your own I beleave on here Steve83 has some nice wire diagrams he has made http://www.supermotors.net/registry/21979/75575
hope that helps good luck

Dale

 

[Broncobowsher]

Pick a harness kit, follow instructions. Too many variables beyond that.

Mini starter can be an issue, but not that big of a deal. The original Bronco ignitions switch (if you use it) is unreliable in giving power to the ignition while in start. In the original wiring that isn't a problem, the "I" wire off the solenoid gives the ignition system voltage during Start. But delete the solenoid and use the one built into the mini starter and you loose that "I" wire and the ignition power during Start. There are a few different fixes for that. Aftermarket (generic) ignition switch has power in ignition while in Start. You can add a relay powered on during Start that will power the ignition circuit. Add a diode from Start to Ignition posts on the switch so Start will power Ignition as well but the diode will block Ignition from powering Start. Must use a properly speced diode to handle the amperage and voltage, not any diode will do.

 

[robofig]

I'm making my own up.

Steve's diagrams don't seen to cover 4G's and do not state the gauge of the wire.

I see a lot of write ups using a 175 amp Mega fuse.

This doesn't make since to me. If I'm using a 130amp alternator, shouldn't the amperage be close to the alternator amperage ?

 

[Broncobowsher]

I'm not a huge fan of fusing the alternator output, but that is how the hew high output stuff is done. It isn't there to protect the alternator, it's there to protect the vehicle from burning up if the alternator becomes a dead short. You don't want it that close to the output rating, you don't want it accidently blowing.

 

[xcntrk]

I'm making my own up.

Steve's diagrams don't seen to cover 4G's and do not state the gauge of the wire.

I see a lot of write ups using a 175 amp Mega fuse.

This doesn't make since to me. If I'm using a 130amp alternator, shouldn't the amperage be close to the alternator amperage ?

3G and 4G is the same wiring. Both are 130-amp in stock form.

Try this:
http://www.bcbroncos.com/3ginstall.pdf

 

[DirtDonk]

Even a stock rebuilt 130 amp 3 or 4G can put out in the neighborhood of 160 amps. Often they have test sheets showing AT LEAST 140 amps stock.

Hence the 150 to 175 amp fuse ratings

Paul

 

[Rustytruck]

BC Broncos has a tech sheet on the 3 G wiring.
http://www.bcbroncos.com/3g.pdf

 

[DirtDonk]

...what gauge wire to use between all components

Between battery and starter relay and starter, and battery to ground: Should be a MINIMUM of 6ga cable. Larger is better though, so for an EB I usually say 4ga. I personally run 2ga and 1/0 welding cable on my projects. 2ga is such a minimal upcharge when purchased as pre-made cables at the local parts store, that it just makes a lot of sense.

Between the alternator and battery positive: 6ga is preferred for modest runs, with 4ga for longer runs. Most with EB's run them straight across from the passenger side alt location to the passenger side battery location, so 6 is fine and is what we use for our Mega-Fuse kits : http://www.wildhorses4x4.com/product/Battery_Charge_Cable_AMG_fused
For short runs, you really could even use 8ga if you have some laying around (it's not that common) but overkill is better.

I shouldn't give so many choices to muddy up what could really be a fairly simple proposition, but I like showing options and reasons.

Paul

 

[robofig]

FYI the 3g AND THE 4g wiring is a little different.

In my town here is the alternator/starter shop Quality Power. Many guys have used their alternators etc. on this site.
They straightened me out as far as the mega fuse and wire gauge.

Broncobowser, I will be using my stock ignition switch. But I will also be using the stock starter solenoid.(basicaly as a relay?).

Will that work? Can you send me a diagram of how this can work?

Thanks again to everyone

 

[DirtDonk]

FYI the 3g AND THE 4g wiring is a little different.

But they can both be operated with the same 3G electrical plug without any trouble.

In my town here is the alternator/starter shop Quality Power. Many guys have used their alternators etc. on this site.
They straightened me out as far as the mega fuse and wire gauge.

Good to know. What did they say? Any differences from what we talk about in general?

Broncobowser, I will be using my stock ignition switch. But I will also be using the stock starter solenoid.(basicaly as a relay?).

Funny you say it that way. The original Ford starter thingy IS a relay. That's what it is and what Ford has always called it. It's just us out in the world that have called it a "solenoid" when by definition, a solenoid is doing physical work, along with it's obvious electrical duties.

Will that work? Can you send me a diagram of how this can work?

Pretty sure Steve83's diagrams show the alternative wiring methods for the two different starter setups. Guess I'll have to check them again to make sure I'm right about that, but that's what I remember.
Basically though, it's a good idea to use the original relay to energize the solenoid and starter to keep feedback from causing the starter to run-on after releasing the key from the START position.

You can use the typical wiring setup, where you swap wires on the relay and use a new wire down to the starter, or wire it like we do on our kits. Our new starters come with a small jumper wire between the large battery cable post and the solenoid's "S" post. This means you use your old wiring as-is and simply put the relay-to-starter cable on the new starter's big post and you're done.

Paul

 

[robofig]

Paul,
Quality power said to use a 175 to 200 amp mega fuse. If the battery is down 200 to 300 amps the alternator could easily produce more than 130-150 amps and blow the fuse, as long as you wire gauge is big enough.

Like I said, I have ripped out all my wiring, going new.
I'm going with modern wiring,EZ wiring harness, but using stock switches.

I will have to check out your site. I do much better with diagrams than with type.

Thanks for your time.

 

[DirtDonk]

And I like drawing diagrams of what I'm always talking about, but I'm really, really bad at it! Wish I was better, or would just take the time to figure out the use of a computer program like Paint or something so I could make more sense. ;D

For locations of components, that's left up to you in most cases, since you're completely modifying it from original, you get to choose the cleanest routing to take.
For instance, I ran a friend's alternator cable all the way back across the intake manifold, down behind the engine and across the firewall down low, then back forward to the battery along the main harness on the inner fender apron. It's longer and more convoluted, but we just didn't want to take the shorter route that most do (and I've done too) of straight from the top of the alternator over to the fender.
Works either way, but whatever suits your fancy is often the "best" way.

Notice the Mega-Fuse holder along the wall there. The EFI fuses and relay pack are along the firewall just behind that.

That's 2ga cable at the battery and 4ga for the alternator. We've since gone to the cleaner looking "military" square lug battery connectors.
The big Radio Shack type of terminal strip is taking the place of the junkyard GM truck buss-bar while waiting to cut it into three separate isolated sections. One is CONSTANT power, one is SWITCHED power, and one is power in START only.

For some confirmation of recommendations, Ford uses 6ga on their cars (and maybe some trucks?) that have shorter runs from the alternator to the battery (or load center) and 4ga on the longer runs. Lots of trucks and vans especially have the 4ga setup.
Ford even uses Mega-Fuses on some applications, while still keeping to the fusible link protection method on others. The fusible links are often visible as a shorter run of two much smaller gauge wires connected to the single larger gauge wire.

Paul

 

[Broncobowsher]

For what its worth, get a premade kit. Even a generic one. It is a better value than bulk wire and doing it yourself.

Couple years ago I wired a boat. Little 16' that was dead simple. Points ignition. True 1-wire alternator. Bow light, anchor light, bilge pump, horn was all the accessory loads. Water, oil and amp were all the gauges. I bought spools of wire, ran out of color options and had to re-use the same color for a few things. In the end I had as much money into that little handful of wires as I did the universal Painless kit I put into the Bronco. The painless kit had nicely labeled wires (printing right on the wire for the function), good generic instructions (it was the generic kit after all), and totally worth it. The only way you are going to beat the price of a premade harness (the generic anyway) with building your own harness is to cut corners and make it a horrible wreck.