Help On 3G Page

[JimsRebel]

Ah! Ok. Thanks for the explanation.

Still, I'm looking for any input I can get on what is out there. Hello? http://www.garysgaragemahal.com/uploads/6/5/8/7/65879365/waving_orig.gif

How I did my 2G to 3G swap:

1: Buy a new Voltage Regulator plug, as you will need all 3 wires, not just 2 wires. Wire in the new plug, just match the colors, adding the stator wire.

2: I back fed the current power wire using a Large Fusible link. This was solder in at the junction point a few inches from the power plug, where 2 wires join into 1 black wire. The original 2G power plug was left so could keep my 2G as a ride along spare.

At this point you will have to decide if you think you truck will ever need more AMPs than the fusible link can provide.

Not sure??? Go to step 3

3: I add a large wire from the ALT output stud > to a 100 amp Circuit Breaker > Battery side of the starter solenoid.

I have a photo of the 2G harness below. I have more photos if you want me to email them directly to you.

.

Jim #2

[85lebaront2]

How I did my 2G to 3G swap:

1: Buy a new Voltage Regulator plug, as you will need all 3 wires, not just 2 wires. Wire in the new plug, just match the colors, adding the stator wire.

2: I back fed the current power wire using a Large Fusible link. This was solder in at the junction point a few inches from the power plug, where 2 wires join into 1 black wire. The original 2G power plug was left so could keep my 2G as a ride along spare.

At this point you will have to decide if you think you truck will ever need more AMPs than the fusible link can provide.

Not sure??? Go to step 3

3: I add a large wire from the ALT output stud > to a 100 amp Circuit Breaker > Battery side of the starter solenoid.

I have a photo of the 2G harness below. I have more photos if you want me to email them directly to you.

.

Jim #2

Ok, here is what I did, I had bought a 1990 F250 as a donor vehicle for the EFI engine and E4OD. The engine to be rebuilt and using the F3TE heads, mild cam and a little more compression. I took the top of the 1990 engine and installed it on my 1986 short block. At the same time I had already decided to change the dash and wiring to a newer configuration. The first change was to mount the polygroove belt system and FS10 compressor along with the 1990 C2 pump with metric fittings. The alternator was still the 2G in 1990, so since I had a pair of them, and the 1990 had the plug changed to a permanent connection I used it initially. You will note that the alternator sense wire and charging output are all tied together at the fusible link rather than separated by the ammeter shunt.

I bought an uprated 3G, 160 amps from someone on FTE who needed the money, I installed it using the huge wire he had with it and used a 200 amp mega fuse in place of the fusible link, other than the M8X1.25 hole in the small lug it fit right in place. I did have a problem with it slipping the belt, but after looking at the 130 amp 3G on my 1994 Taurus, I found the pulley that came with it (which was the same as the 2G had) was quite small. I put an extra Taurus pulley on and never had any more problems. I did drill out the hole and tapped it for the 3/8-16 bolt the 2G used. It is essentially identical to the Taurus 3.8L 130 amp unit.

Since both the 1990 and the later 1996 wiring use a voltmeter rather than an ammeter and I had the 2G wiring, when my son's 1986 F150 ate the 2G alternator we installed the 1990 one, no charge still. Went into the 1986 wiring and found the portion where the alternator feeds in at the junction of the two fusible links that the BK/O wire from the alternator feeds into at splice S202 was burned, we were seeing 18 + volts at the alternator, but the regulator which is connected on the other end of the shunt, was only seeing the battery voltage, or about 12V. I am sure the intent of this wiring was to have the alternator keep the battery up to 13.8-14.2V, but any interruption of the charging output causes the alternator to overcharge. Since the feed into the main electrical system is the other end of the shunt, this can cause burned out lights among other things.

[Gary Lewis]

Ok, here is what I did, I had bought a 1990 F250 as a donor vehicle for the EFI engine and E4OD. The engine to be rebuilt and using the F3TE heads, mild cam and a little more compression. I took the top of the 1990 engine and installed it on my 1986 short block. At the same time I had already decided to change the dash and wiring to a newer configuration. The first change was to mount the polygroove belt system and FS10 compressor along with the 1990 C2 pump with metric fittings. The alternator was still the 2G in 1990, so since I had a pair of them, and the 1990 had the plug changed to a permanent connection I used it initially. You will note that the alternator sense wire and charging output are all tied together at the fusible link rather than separated by the ammeter shunt.

I bought an uprated 3G, 160 amps from someone on FTE who needed the money, I installed it using the huge wire he had with it and used a 200 amp mega fuse in place of the fusible link, other than the M8X1.25 hole in the small lug it fit right in place. I did have a problem with it slipping the belt, but after looking at the 130 amp 3G on my 1994 Taurus, I found the pulley that came with it (which was the same as the 2G had) was quite small. I put an extra Taurus pulley on and never had any more problems. I did drill out the hole and tapped it for the 3/8-16 bolt the 2G used. It is essentially identical to the Taurus 3.8L 130 amp unit.

Since both the 1990 and the later 1996 wiring use a voltmeter rather than an ammeter and I had the 2G wiring, when my son's 1986 F150 ate the 2G alternator we installed the 1990 one, no charge still. Went into the 1986 wiring and found the portion where the alternator feeds in at the junction of the two fusible links that the BK/O wire from the alternator feeds into at splice S202 was burned, we were seeing 18 + volts at the alternator, but the regulator which is connected on the other end of the shunt, was only seeing the battery voltage, or about 12V. I am sure the intent of this wiring was to have the alternator keep the battery up to 13.8-14.2V, but any interruption of the charging output causes the alternator to overcharge. Since the feed into the main electrical system is the other end of the shunt, this can cause burned out lights among other things.

Jim - Thanks for your response and your offer of more pics. I think I understand how you did your conversion, but while it obviously works for you I think we want an easier way to recommend to others. And on the pics, let's see where this goes as right now I think I have what I need. But thanks again.

Bill - The later schematic sure looks familiar as that's where I'm getting the 3G schematic I'm dropping into the 1 & 2G schematics. But your experience with the burned junction explains why Jim/ArdWrknTrk recommends wrapping the sense wire right back to the output at the alternator. (Which I've failed to do on the schematics so far, I'm now remembering.)

[85lebaront2]

Jim - Thanks for your response and your offer of more pics. I think I understand how you did your conversion, but while it obviously works for you I think we want an easier way to recommend to others. And on the pics, let's see where this goes as right now I think I have what I need. But thanks again.

Bill - The later schematic sure looks familiar as that's where I'm getting the 3G schematic I'm dropping into the 1 & 2G schematics. But your experience with the burned junction explains why Jim/ArdWrknTrk recommends wrapping the sense wire right back to the output at the alternator. (Which I've failed to do on the schematics so far, I'm now remembering.)

The real issue with it, the 2G goes full output with no place to really load it down, if it doesn't fry every electronic piece on the vehicle, it can still set itself on fire like a Vietnam era Buddhist monk.

[ArdWrknTrk]

The real issue with it, the 2G goes full output with no place to really load it down, if it doesn't fry every electronic piece on the vehicle, it can still set itself on fire like a Vietnam era Buddhist monk.

The 2G had the sense wire on the far side of the fusible link where the two 10Ga. output wires splice together.

If the fuselink burns the alternator has no sense, and just keeps ramping up, because it's output can't effect the running voltage of the system, and the regulator wants to see it's set point, not 12.6V or whatever the battery has left after the ignition coil and any accessories.

The other problem is when the charge plug corrodes.

It gets really hot and the brass springs lose their grip on the output pins.

If the plug gets hot enough it melts through and the brass terminals ground against the case.

Oh boy! Then it's off to the races.

The windings cook their insulation, the diode board can't handle the current charging into a dead short and it has a meltdown if it doesn't just catch on fire with the flames fanned by the very fan meant to cool it.

It's a lot better to have the y/w wire read the output stud.

There shouldn't be any appreciable drop in the big charge cable, and the voltmeter ( and idiot light in my case) will show the alternator is kaput.

[Gary Lewis]

The 2G had the sense wire on the far side of the fusible link where the two 10Ga. output wires splice together.

If the fuselink burns the alternator has no sense, and just keeps ramping up, because it's output can't effect the running voltage of the system, and the regulator wants to see it's set point, not 12.6V or whatever the battery has left after the ignition coil and any accessories.

The other problem is when the charge plug corrodes.

It gets really hot and the brass springs lose their grip on the output pins.

If the plug gets hot enough it melts through and the brass terminals ground against the case.

Oh boy! Then it's off to the races.

The windings cook their insulation, the diode board can't handle the current charging into a dead short and it has a meltdown if it doesn't just catch on fire with the flames fanned by the very fan meant to cool it.

It's a lot better to have the y/w wire read the output stud.

There shouldn't be any appreciable drop in the big charge cable, and the voltmeter ( and idiot light in my case) will show the alternator is kaput.

Yep, I'm in full agreement. So if I don't show the sense wire wrapped at the alternator in what I do remind me, please. Albeit gently?

There is sooooo much to do on this to get it "right" that it is taking a while.

[ArdWrknTrk]

Ok, here is what I did, I had bought a 1990 F250 as a donor vehicle for the EFI engine and E4OD. The engine to be rebuilt and using the F3TE heads, mild cam and a little more compression. I took the top of the 1990 engine and installed it on my 1986 short block. At the same time I had already decided to change the dash and wiring to a newer configuration. The first change was to mount the polygroove belt system and FS10 compressor along with the 1990 C2 pump with metric fittings. The alternator was still the 2G in 1990, so since I had a pair of them, and the 1990 had the plug changed to a permanent connection I used it initially. You will note that the alternator sense wire and charging output are all tied together at the fusible link rather than separated by the ammeter shunt.

I bought an uprated 3G, 160 amps from someone on FTE who needed the money, I installed it using the huge wire he had with it and used a 200 amp mega fuse in place of the fusible link, other than the M8X1.25 hole in the small lug it fit right in place. I did have a problem with it slipping the belt, but after looking at the 130 amp 3G on my 1994 Taurus, I found the pulley that came with it (which was the same as the 2G had) was quite small. I put an extra Taurus pulley on and never had any more problems. I did drill out the hole and tapped it for the 3/8-16 bolt the 2G used. It is essentially identical to the Taurus 3.8L 130 amp unit.

Since both the 1990 and the later 1996 wiring use a voltmeter rather than an ammeter and I had the 2G wiring, when my son's 1986 F150 ate the 2G alternator we installed the 1990 one, no charge still. Went into the 1986 wiring and found the portion where the alternator feeds in at the junction of the two fusible links that the BK/O wire from the alternator feeds into at splice S202 was burned, we were seeing 18 + volts at the alternator, but the regulator which is connected on the other end of the shunt, was only seeing the battery voltage, or about 12V. I am sure the intent of this wiring was to have the alternator keep the battery up to 13.8-14.2V, but any interruption of the charging output causes the alternator to overcharge. Since the feed into the main electrical system is the other end of the shunt, this can cause burned out lights among other things.

Bill, is your schematic for a 1990 truck?

Because my '87 2G had the sense wire attached to the fender relay (on the other side of the fuselink)

I know it came that way, because I had never touched it.

[Machspeed]

Bill - The later schematic sure looks familiar as that's where I'm getting the 3G schematic I'm dropping into the 1 & 2G schematics. But your experience with the burned junction explains why Jim/ArdWrknTrk recommends wrapping the sense wire right back to the output at the alternator. (Which I've failed to do on the schematics so far, I'm now remembering.)

Gary, does this mean you will be making some changes to your current wiring schematics?

[Gary Lewis]

Bill - The later schematic sure looks familiar as that's where I'm getting the 3G schematic I'm dropping into the 1 & 2G schematics. But your experience with the burned junction explains why Jim/ArdWrknTrk recommends wrapping the sense wire right back to the output at the alternator. (Which I've failed to do on the schematics so far, I'm now remembering.)

Gary, does this mean you will be making some changes to your current wiring schematics?

Yes, sorta. What I was talking about with the sense wire is very minor. The diagram shows it connecting with the output at the megafuse. Instead I'd shorten the sense wire and put it directly on the output stud.

Electrically there's no difference, but if the connection between the sense wire and the output wire is done at the megafuse and then the output wire comes loose at the output stud the sense wire won't see what is happening. But if you put the two together at the output stud there's a chance the sense wire will still be connected to the output.

And I'm making changes in the background on the Voltmeter tab. I'm not done there, but I would appreciate all input, especially yours, on the 2G stuff. After all, you are the test case. So, does this make sense to you?

[Machspeed]

Yes, sorta. What I was talking about with the sense wire is very minor. The diagram shows it connecting with the output at the megafuse. Instead I'd shorten the sense wire and put it directly on the output stud.

Electrically there's no difference, but if the connection between the sense wire and the output wire is done at the megafuse and then the output wire comes loose at the output stud the sense wire won't see what is happening. But if you put the two together at the output stud there's a chance the sense wire will still be connected to the output.

And I'm making changes in the background on the Voltmeter tab. I'm not done there, but I would appreciate all input, especially yours, on the 2G stuff. After all, you are the test case. So, does this make sense to you?

Sorta, I'm in and out on it, as I have other things going on. Tonight, I'm going to pull my 3G, as it is temp fitted, and begin the wiring process. May be lots of questions.