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Topic: Need help badly with 1g to 3g in 84svo 5.0 (Read 3353 times) previous topic - next topic

Need help badly with 1g to 3g in 84svo 5.0

Ok i do not have a cougar or a t bird i have a 84 mustang svo 2.3 turbo that was converted to 92 5.0 high output
Im trying to get some help but not much on the mustang sites

It has an ampmeter that is always at halfway point even with vehicle off

I have a externally regulated 1 g  , it has 3 wire connections on the alternator, i need to replace it because this alternator was creating a parasitic draw

I have a rjm injection 3 g alternator upgrade harness

I replaced it with a 3G from a 94-95 mustang that has A,S,I conenctions and a stator hook up Also has a positive battery post which i connected to the solenoid on the fender

the external regulator has 4 connections the I wire (not sure of color was replaced with a thin blue solid blue wire)  runs into the fuse box under blower motor,,,,,
The A wire is yellow and white and I hooked it to the A conenction on the internal regulated 3G
The S wire is green and red and i hooked it to the I wire on the 3 G alternator

The fourth wire at the external regulator is orange and light blue
and i do not have this hooked up

all stock wires for alternator arent hooked up and were replaced with good wire from there perspective positions as stated above

there are no draws in the car, when sitting it has .00 for current draw

My battery does not charge, in fact the voltage when sitting is 12.5 or so and when i start it it has 12.2 volts, after couple days i gotta swap in a fully charged battery or it wont crank

where did i go wrong?
 need some help please, not sure if im ready to take the alternator out and test it at a local shop

Need help badly with 1g to 3g in 84svo 5.0

Reply #1 –
are you talking about the wires at the alt? if you are all you need is the green/red wire to hook it up. the yellow on the 3g reg plug goes to tge batt stud on the alt. the wht/bl wire goes to the stator plug on the alt. all thoes wires on your 1g come from your ext reg. disconnect the ext reg run your grn/ rd wire to the 3g. hook everything up and you should be good to go. there is an excelent write up on it in the sticky section of electral tech.
louie  :birdsmily:
[SIGPIC][/SIGPIC]       
My famous last words:
It seemed like a good idea at the time.        88TC R.I.P.      88 Sport build in progress

Need help badly with 1g to 3g in 84svo 5.0

Reply #2 –
the 4 wires i was talkin about are off the external regulator that was in there pre 3g

i tried alot of stuff but cant get it to charge maybe its a bad alternator

i also read the thread aobut it in electrical tech and that was the way i had it hooked up


do i maybe need to have the stock alternator wires hooked up to the alternator too?

deja vu

Reply #3 –
Not sure if I can be of any help personally, but you might try reading all of this
http://www.foxtbirdcougarforums.com/showthread.php?t=18555

The info you need is there, barring any wiring bugs.
__________________
Twin '85 TCs
White/ Grey 2-tone
#1 (left): undergoing top-to-bottom rebuild     
#2 (right): DD, power everything (sorta)
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Need help badly with 1g to 3g in 84svo 5.0

Reply #4 –
see link below,, lots of sweat and hard work went into the the thread but your answer is in post 50.  Be advised  you need to report back on  your results especially since it "was" a 2.3 to start with and I am just as curious as you about the ammeter.  To answer your question my own way, you need to make your wiring and alternator look like the picture.  Please  understand you are migrating away from the external regulator so do so now and prepare your harness as described.

Also,, verify your alternator is not defective so your not chasing your tail.

http://www.foxtbirdcougarforums.com/showthread.php?t=13641&page=5

Need help badly with 1g to 3g in 84svo 5.0

Reply #5 –
Did the ammeter work before you changed the alternator?
From my 84 shop manual; the original setup had no wire on the "I" terminal of the external reg.
The green/Red wire to the "S" of the external reg should be hot with the ignition in run. If it is not, someone probable haywired a hot in RUN wire to the "I" of the external reg to "fix" the problem.

If the wire you put on the "A" of the 3g is hot at all times.
And if the wire you put on the "I" of the 3G is hot in RUN, the alternator should work.

Once you get it working you will need to decide whether you want the ammeter to work or if you want to increase the wire size to take advantage of the additional current available from the 3G.

Let us know.

Need help badly with 1g to 3g in 84svo 5.0

Reply #6 –
well at least i am getting some answers here

not sure about ampmeter i didnt drive car much before putting 3 g into it

I will check these wires with my voltometer tommorow

so heres what i do correct??

Check the wire hooked up to the I on the alternator,it should be hot at all times, ill chekc it with the car off

then i will check the wire that is running to the A on the alternator, this wire should only be hot when the car is running?? so i should check it while the car is off then start it up and check it again...

Ill also check the mysterious I wire on the external regulator that runs into the blower motor slot on the fuse box(wires just stuck in along side fuse)
that haywiring may make sense now, maybe that is telling the alternator to charge when the vehicle is started causing current to flow thru the blower motor fuse box slot...

Ill check into it and make sure i post the results, appreciate the help

Need help badly with 1g to 3g in 84svo 5.0

Reply #7 –
Quote from: 84svo5.0;214196
Check the wire hooked up to the I on the alternator,it should be hot at all times, ill chekc it with the car off

NO.
The "I" terminal on the 3G should be hot when the ignition switch is in run. Don't start the car. You can unplug the cable from the 3G if that will make it easier to check.

The "A" terminal should be hot at all times.

Need help badly with 1g to 3g in 84svo 5.0

Reply #8 –
ok some new info has arisen here the orange and light blue wire from the external regulator was one of the original 3 wires that were on the old externally regulated 1g  checked some wires but didnt have time to do much i had to take the car to the body shop for new paint

Need help badly with 1g to 3g in 84svo 5.0

Reply #9 –
The orange/light blue wire from the external reg to the 1G was the field wire.

The 3G doesn't need this. It is internal with the built-in reg.

Need help badly with 1g to 3g in 84svo 5.0

Reply #10 –
Ok here is some more information to add
the battery is in the hatch, should i run the 4 gauge wire off the alternator output directly on the battery?

it looks like its going to the solenoid on the fender wall right now, and it is not on the same post as the cable from the battery that runs into the solenoid


I also just checked the voltages on the A and I wire

i was getting constant voltage on the A wire 12.58

I got no voltage on the I terminal off of the 3g at standstill, and also no voltage when the key was in run position ( i unplugged the wire to check it)

Need help badly with 1g to 3g in 84svo 5.0

Reply #11 –
Positive terminal battery to "forward" post on solenoid.
Negative terminal battery to solid ground (make sure the ground is clean, no paint corrrosion etc)
Heavy cable+fuse from alternator to "forward" post on solenoid.
Heavy cable from solenoid "rear" post to starter.
Check the engine ground strap while your're at it.

By "forward" I mean the one to your left, if the solenoid is mounted on the driver's side wheel well and you're standing behind it.


(edit)  If you've already tried the combo as you stated, you might have blown a fuse or three. (/edit)
__________________
Twin '85 TCs
White/ Grey 2-tone
#1 (left): undergoing top-to-bottom rebuild     
#2 (right): DD, power everything (sorta)
[SIGPIC][/SIGPIC]

Need help badly with 1g to 3g in 84svo 5.0

Reply #12 –
hmm a mechanic shop is the one that changed the way the wiring was  I had it running off the alternator output to the same post the battery cable was hooked on

so does anyone know why my I terminal is not getting hot in run position? talking about the I terminal off the alternator here, should i actually have the car running when checking this?

should i try a battery jus in the front and hook the alternator output cable to it and the thuicker ground wire i ran off the alternator bracket to it and see if it charges?

im pretty much about to take the alternator out and take it to autozone havem test it to see if its even any good, any suggestions?

Need help badly with 1g to 3g in 84svo 5.0

Reply #13 –
hah ok i looked at my solenoid and they have the alternator output running to the same post that a thick black wire is on that runs to the engine block it looks like

Need help badly with 1g to 3g in 84svo 5.0

Reply #14 –
However i disconnected the cable stated above and im still not getting a charge and the I terminal on the alternator is not getting hot

If the A is constantly hot, then how does the alternator determine when the I gets hot??? does it get hot when the alternator spins or what? as far as i determine theres nothing letting the alternator know when the I should be hot, i only have the 1 wire hooked uo thats constant, and the other wire that is supposed to go hot when the key is in run