2G ALT, New VR connector with 3 wires

[Max Capacity]

I hope it's ok to ask for help here. I'm trying to help a new member over there figure out which wire to use on the new 3 wire VR connector when it's installed on a new 2G ALT. Gary, would you know the answer ? The schematic shows the wrong placement of the green/red wire from VR on 2G ALT, Connector C186. My C186 has the yellow/white and green/red next to each other, yet the schematic shows them separated...

https://www.ford-trucks.com/forums/1740652-fml-new-alt-isnt-charging-please-help-4.html

 

[Gary Lewis]

Yes, it is fine to ask for help here for someone on FTE. There's lots of good people there, and particularly Dave/Franklin2. So if you have him helping you then I probably can't be of any more help.

I say that because all I know about the 2G is what is in the EVTM - the '86 EVTM as the '85 EVTM shows a 1G. But I find it really strange that there are two different voltage regulators for them that have different connections.

Anyway, sorry but I've read through the thread and don't have anything to add. I'd follow Dave's lead.

[ArdWrknTrk]

Why did the guy change the regulator plug?

If you read the TSB it says to replace the charge connector.....

Yes, most new 2G's come with a hard wired pigtail and heat shrink butt connectors (to get rid of the faulty plug blade connectors)

The two hot (bk/or) battery leads from the 2G should go to splice 202 which feeds the cab through Y-37, the far side of the shunt B/O-38 and the far side of the ammeter Y/LG 654.

At the other end of the shunt (S203) we have the Y/W "sense" wire going to the regulator and the R/O wire(also coming from C610) that feeds the ammeter.

These all join a single fusible link at Splice 203 before attaching to the always hot stud of the starter relay.

The choke should be feeding from the white & black at the 2G output (not "from ignition on") because if the engine stalls while warming up the choke will continue to open.

If his regulator is labeled( A S I ) then he doesn't need to feed stator current to the center wire, but he DOES have to connect the Y/W "sense" wire to A and the LG/R (trigger) ignition on wire to I.

Edit: I see in post 37 his regulator is indeed labeled ASI. So, he only needs the two end wires connected.

The '86 EVTM has the correct diagram..

 

[Max Capacity]

Why did the guy change the regulator plug?

If you read the TSB it says to replace the charge connector.....

Yes, most new 2G's come with a hard wired pigtail and heat shrink butt connectors (to get rid of the faulty plug blade connectors)

The two hot (bk/or) battery leads from the 2G should go to splice 202 which feeds the cab through Y-37, the far side of the shunt B/O-38 and the far side of the ammeter Y/LG 654.

At the other end of the shunt (S203) we have the Y/W "sense" wire going to the regulator and the R/O wire(also coming from C610) that feeds the ammeter.

These all join a single fusible link at Splice 203 before attaching to the always hot stud of the starter relay.

The choke should be feeding from the white & black at the 2G output (not "from ignition on") because if the engine stalls while warming up the choke will continue to open.

If his regulator is labeled( A S I ) then he doesn't need to feed stator current to the center wire, but he DOES have to connect the Y/W "sense" wire to A and the LG/R (trigger) ignition on wire to I.

Edit: I see in post 37 his regulator is indeed labeled ASI. So, he only needs the two end wires connected.

The '86 EVTM has the correct diagram..

Thanks for replying.

In post 48 over there, you'll see where my 86' 302EFI has the VR wires next to each other. That's the 2nd replacement 2G in the past 5 or 6 years. The ALT was installed Nov 2021.

The OP in that thread said his connector at the VR was melted, there's a picture it earlier, but I'll say it didn't look that bad.

[ArdWrknTrk]

Thanks for replying.

In post 48 over there, you'll see where my 86' 302EFI has the VR wires next to each other. That's the 2nd replacement 2G in the past 5 or 6 years. The ALT was installed Nov 2021.

The OP in that thread said his connector at the VR was melted, there's a picture it earlier, but I'll say it didn't look that bad.

Is your regulator labeled AIS?

Honestly, I don't know why anyone would go back with another 2G.

Marginal charging and cooling. I had a couple of rectifier boards go bad.

But it took me only one time cooking that charge plug to realize it wasn't one of Ford's "Better Ideas"

[ArdWrknTrk]

I see RYans460 just signed up over here.

Hopefully we can give him the answers he needs....💡

[JimsRebel]

I see RYans460 just signed up over here.

Hopefully we can give him the answers he needs....💡

All 1986 G2 alternator voltage regulator plug I have seen are not wire per the diagram above.

A long time ago, Gary had a 2G to 3G conversion page with a photo of the alternator harness. It matched everyone I have seen. With the green wire going to the center "S" input. Just 2 wires.

There was an old thread... When Gary was asking for input, as he was making a 2G to 3G info page. The 2 wire plug VR was talked about then, in that thread.

Jim number 2

 

[JimsRebel]

All 1986 G2 alternator voltage regulator plug I have seen are not wire per the diagram above.

A long time ago, Gary had a 2G to 3G conversion page with a photo of the alternator harness. It matched everyone I have seen. With the green wire going to the center "S" input. Just 2 wires.

There was an old thread... When Gary was asking for input, as he was making a 2G to 3G info page. The 2 wire plug VR was talked about then, in that thread.

Jim number 2

https://forum.garysgaragemahal.com/Help-On-3G-Page-tp86569p88610.html

[ArdWrknTrk]

https://forum.garysgaragemahal.com/Help-On-3G-Page-tp86569p88610.html

Appreciate the link.

This forum is indeed an enigma sometimes...

[Ryans460]

All 1986 G2 alternator voltage regulator plug I have seen are not wire per the diagram above.

A long time ago, Gary had a 2G to 3G conversion page with a photo of the alternator harness. It matched everyone I have seen. With the green wire going to the center "S" input. Just 2 wires.

There was an old thread... When Gary was asking for input, as he was making a 2G to 3G info page. The 2 wire plug VR was talked about then, in that thread.

Jim number 2

Jim, from what I can tell from that other thread is that the 3wire plug is physically adaptable to the 3G swap, but not necessarily without changes. The real issue is how many different variables came from the factory.

The above diagram shows the VR "S" not used and the green wire connected to VR "I". This is the only diagram that shows this, but it's the easiest next step as this is how I have it currently(not working for those not following the FTE thread) wired.

I will cut the Stator to VR "S" wire and see if anything changes.

If that doesn't work, I will move the Green/red wire from the VR "I" to the VR "S" like my truck was before this debacle.

Max, in one of your pics it looks like your ALT B+ wires are divorced.

The diagrams/schematics and my original wiring all show those two splicing together.

Do yours splice out of picture frame, or how do they route to the solenoid and wiring harness?

Hello everyone. Thanks for having me here in the Garagemahal.

Long time reader....first time caller!