• Welcome Visitor! Please take a few seconds and Register for our forum. Even if you don't want to post, you can still 'Like' and react to posts.

alternator upgrade question


cozz

Member
Joined
May 3, 2009
Messages
18
Vehicle Year
1990
Transmission
Manual
wondering if anyone can help me here. I have a 90 ranger with the 2.3 and an extremely anemic alternator. I added an electric rad fan and the stock 65 amp just ain't doing it. Been through a few lifetime alts from autozone, and I just wanna go to a 3g from a 95 mustang (140 amp) I noticed these are 1 wire, mine has the crappy 3 wire plug. Am I correct in assuming that the 2 big fat wires can be spliced and put to the large red connector on the alt? and if so-where does the smaller white wire with black strip go? is that for the gauge?
This is a beater work truck and I don't wanna order a fancy 3 million amp alternator off the net, just want to be able to run the A/C fan and wipers at the same time. Thanks for any advice, Kevin
 
You will want to completely eliminate the 3 wire (meaning the 2 black/orange wire and 1 white wire plug) system. It is junk. I melted the sheathing on those black wires in my Mustang with a stock 85 amp alternator. The wiring is very simple actually. You need to get a stator wire (it will be white with a black stripe) out of the donor vehicle. The 3 wire plug for your current voltage regulator is that same, it just needs a bit of rewiring. Then all you need is a 4 gauge wire to run as your main. Wire it like so:
 

Attachments

  • 3gwiring.jpg.gif
    3gwiring.jpg.gif
    37.2 KB · Views: 215
thank you

I didn't quite understand your pic, until I found this site
http://oldfuelinjection.com/?p=63
shows both my current system and the system for the new alternator
Now I gotta go talk the guy at autozone into giving me credit for the alt I just bought(3rd one)- it wouldn't hold max charge at idle, none of the last 3 I've bought so far will, the electric fan in a 23 year old truck = bad charging, even with all the important wiring thoroughly cleaned up.
 
You do need to run a larger "Battery" wire from the alternator, for the larger AMPs.
You will fry the original wire or wires.

Also 1 wire Alternators don't charge at idle, you mentioned that about the current alternator.
I think all 1 wire alternators have a "speed" sensor of sorts, that's how the work with only 1 wire, once alternator is turning at a preset-RPM it will start outputting voltage, on some, once the "speed" is reached they will continue to output voltage at any speed, even lower RPM, and will stop outputting voltage only when alternator RPM is 0, stopped.
Check the specs on the one you are getting.
And in most cases you do not want to run the higher amp alternator thru your AMP gauge, check very carefully about that hook up.
Some 1 wire alternators have a second hook up, some times behind a rubber plug, this is for a "battery" dash light or in some case an dash board AMP meter.

An alternator is like an electric motor, in reverse, if connected directly to a battery it will act like an electric motor draining the battery, so there needs to be an "OFF" switch, that's what 1 of the extra wires was for, it goes to the key switch and turns "ON" the alternator, when key is on.
The 1 wire alternator doesn't have this, so is "OFF" when not spinning, and only turns "ON" when spinning fast enough.


Often you will need to change the pulley size(smaller) to get the 1 wire alternator to spin at a faster speed, to enable charging at idle.
Once alternator is installed(and hooked up) start engine and check battery voltage, if its in the 12.5-12.9 range then alternator is not charging, raise RPM slowly until you get a voltage at the battery of 13.6-13.9, it should just "pop up" when alternator turns on, should be about 1.1 volts above battery voltage.
1.1 volts above battery's voltage will maintain a charge, 1.2 volts and up will recharge a 12v battery.
 
Last edited:
yep

gonna ad another 10 gauge fused wire directly to the battery, and I think from the pics(not always representative of the actual product) that the 95 mustang 5.0 alt has a smaller pulley. There is a guy up at autozone, that I try to deal with exclusively, older dude, gonna see if he'll work with me on this- he's customer orientated. Hopefully at least I can use this stock one as a core. From what I see in the diagrams, this should be a really easy swap, as they're both ford alts. Thanks for the help guys
 
gonna ad another 10 gauge fused wire directly to the battery

Wait... you are saying that you are going to run an additional wire? So, you will have 3 wires going from the alternator to the battery? That is insane. If you are going to pony up on a 130 amp alternator, why cheap out and create a fire hazard because you were too cheap to spend 10-15 dollars on a piece of wire?

Forgive me if I am reading that wrong... but that is utterly insane the way I interpreted it.
 
worked like a champ

yes- here's what I did:
1)chopped off big crappy plug, ran 2 large existing wires to big red terminal on alt
2)ran battery cable wire from big red terminal on alt to battery+
3)ran small white wire with black stripe to the single stator plug on alt (had to find special terminal at Pep boys in the help section- nobody had it, even ford)
4)plug in small 3 wire plug into alt, no modifications necessary, and the gauge still works

I did have to grind away a little of the ps bracket
I'm not concerned about fire, the extra wire is 4 gauge and goes to the battery, and so does the relay for my electric rad fan, which is what was straining my system. You have to remember, having more amps present doesn't melt wires- it's the amount of amperage you're drawing through the wires that melts them. Now the extra draw goes through a heavy cable right to the power sucker. Of course the factory harness gets more amps too- but it only draws what it needs. I do need to get a fuse for the heavy cable probably though

And oh, here's a good word for the guys at my Autozone- I went in and told em about my dilemma and what I planned to do- they let me buy the 3g alt, take it home and fit it, and then let me bring the old unit back, and refunded me for it (guess they got tired of me bringing the stock one back 3 times)

I could have just left the 2 big wires from the big crappy plug capped off and not use them, but ain't nothing wrong with redundancy on a truck with 300,000 miles.

This upgrade is awesome, the gauge doesn't even flinch when I run everything. And oh donor was a 95 mustang with a 5.0, I never could find one for a Mercury Marquis as listed in the alt page here on TRS. It actually had a larger pulley, but the belt fit and it works great
 
The new 4ga wire is fused....right?
The wire size is a two-way street, yes draw is part of what needs to be considered.
But alternator output is the other direction of the street, alternators do fail and output way over rated volts/amps.
Fire is a concern but melted insulation is worse in that it can send high volts where you don't want them and dead short the battery, and the battery is usually new when this happens, lol.

The amp gauge does move...right, so lower before starting and then higher after starting?
 
i would go here have three of their alt for the last 5 year running strong a 170 and a 135 in the 94 rangers and a 200 amp in the 97 Taurus. they do custom alts too. and they are fairly cheap. so how much could a email hurt to find out he stocks it? if it's like $150 instead of doing some screwing up.. i think would be better...


http://www.motorcityreman.com/high-amp-alternators.html
 
Fire is a concern but melted insulation is worse in that it can send high volts where you don't want them

Yes sir. And those two factory wires are garbage. I may still have the wires I cut out of mine in my recycle pile. I'll have to photograph them if I do. I feel overwhelmingly lucky that no major issues were caused by them It is probably 3 inches of bare wire - all done with an 85 amp alternator too.
 
i would go here have three of their alt for the last 5 year running strong a 170 and a 135 in the 94 rangers and a 200 amp in the 97 Taurus. they do custom alts too. and they are fairly cheap. so how much could a email hurt to find out he stocks it? if it's like $150 instead of doing some screwing up.. i think would be better...


http://www.motorcityreman.com/high-amp-alternators.html

Wish i woulda gone here first instead off buy the 7069fbull that tuff stuff sales, its a 140amp one wire that retails 150$
 
If the alternator manufacturer say 4 ga wire then go 2 ga, just to be covered.

Also, all for not here, what about your grounding system, it can kill a new alternator install or at least reduce the output of the alternator.

There is something called the big-3 but I do not know exactly what it is about, here is my thought.

Add a new 2 ga, 4 ga min, wires as follows: (better to go bigger than smaller)

1) From the engine to the frame
2) From the frame to the negative terminal on the battery
3) From the alternator body to either the engine/frame mounting point or directly to the battery.
4) from the negative battery terminal to one of the mounting bolts on the starter.

Also, consider a new ground wire to the body of the vehicle, the OEM wire/braided cable is poor at best and may already have broken off.

Remember to get to bare metal when making any electrical connection and use a good quality, waterproof dielectric grease on and in between all electrical connection.

Once the body ground strap breaks, and believe me it is a minimum size to begin with, all that is left for the return current to run through is the mounting hardware.
It doesn’t sound too bad, right, but think about all of the rust, grease, oil, dirt and road grime that is built up and in between all of the mounting points and this all adds up to one very bad connection and almost no current flow.
Easiest way out is to add a good sized grounding wire from the body back to the negative battery terminal.

Extra work, yes, but it will be worth it when everything is running correctly, no more ground problems and things will stop burning out.

One more thing, add the ground wire where you can get to the mounting hardware on the inside of the vehicle, it will give you a good grounding point for higher currect draw components.

I’ll get off the box now.
 
When in doubt about ground get jumper cables, clip one to the block, one to the frame, and the other two to the batt negative. You will never run out of ground if you do that.

Postin' from teh Galaxy
 

Sponsored Ad


Sponsored Ad

TRS Events

Member & Vendor Upgrades

For a small yearly donation, you can support this forum and receive a 'Supporting Member' banner, or become a 'Supporting Vendor' and promote your products here. Click the banner to find out how.

Recently Featured

Want to see your truck here? Share your photos and details in the forum.

Ranger Adventure Video

TRS Merchandise

Follow TRS On Instagram

TRS Sponsors


Sponsored Ad


Sponsored Ad


Amazon Deals

Sponsored Ad

Back
Top