Help On 3G Page

[Gary Lewis]

ArdWrknTrk wrote

But we need participation.
The few of us here are not really representative of the intended audience for a tutorial.

Amen, brother!

[Machspeed]

Ok fellas, was hoping to get out in the shop tonight but just got in from work....long day! Regardless, want to thank you two for your dedicated efforts in helping me with this. I am still waiting on a converted voltmeter and am uncertain as to when Rocketman will have it finished. That's another story. Right now my dash does have an ammeter in it, as I sent out another ammeter I had. Won't be hooking up the battery until I have everything installed.  

My desire is to cut up as little as possible yet get the most out of what I do. As I said earlier, wish to keep my connector on the opposite side of the alternator virgin, if possible. Don't care about the alternator side. I do not fear wiring if I know precisely where and what to connect. I can tell you, I prefer to measure battery voltage and I do have relays if I need to use them. If you will, point me in the best most logical direction and I will go that way?

Thanks!    

[ArdWrknTrk]

John, according to the EVTM your 351 HO should already have a relay in place.
Gary should know which wire is positive after the Rocketman conversion.

It is fine to check voltage from the starter relay or the Megafuse.
All the new cables you install will reflect what's up with the battery.

My regulator pigtail has little raised LSA molded on it.
But I don't know where Painless might source their parts, so have a look when you can?

[Gary Lewis]

John - We are close to having agreement on what that should look like.

All - Please help me think through this.  On the 2G conversion I was saying that we can use the choke relay for the HO trucks or another relay for the non-HO trucks.  BUT, what I'd forgotten is that the HO relay gives us the positive feed to the voltmeter and a standalone relay can either be the positive feed or the negative feed.

So, thinking of the easiest way for people to do this, and the best way for us to explain it, I present two options.  On the left is the way to use the HO's choke relay.  Note that you have to change both the positive and the negative leads going to the voltmeter.

On the right is using a new relay.  Note that you do not have to change the positive side going to the voltmeter.  You only have to change the negative side.

I am wondering if we should recommend that the easiest way through this is to retain the shunt and keep the R/O wire connected to the starter relay to give the voltmeter battery voltage.  Then use a relay to ground the voltmeter pulled in with the stator output.

In other words, one solution for everyone.  No using the LG/R wire to feed the voltmeter for some and a relay for others.  No choke relay for the HO people.  Just one solution that gives everyone a good solution.

Thoughts, please!

[ArdWrknTrk]

  

You've got me real confused here!
An analog voltmeter will only read positive deflection using ONE polarity.
But I don't even have a place for a converted ammeter so...

What are you trying to show, and why are you trying to confuse something that should be as simple as possible?

[ArdWrknTrk]

I mean, I get it.
You're trying to create a switched path to ground.

I guess I don't enough about the old ammeters to have an opinion.

[Gary Lewis]

Yes.  Either we switch the positive side or the negative side.  If we switch the negative side then we can leave the positive wire alone.  Seems like the easiest thing to do.

[Machspeed]

Gary, I'm thinking one good solid solution for everyone. Really, it's a lot of work for you and can be confusing for others.

[Gary Lewis]

John - I'm beginning to think you are right.  And I really appreciate your input as you are probably more representative of the "normal" users, meaning those of us who haven't been playing with electrics/electronics for decades.

But there have to be two solutions, one for those with an ammeter and one for those w/o.  And, since the 2G harness is different, we need to show those separately.  However, the end solution for both of those is the same.

And, by doing it that way we might not need the separate Voltmeter tab.  I think I see a way to make things much less complicated.

Stand by...  

[Machspeed]

Okay, here's another question, one I think I already know the answer to but want confirmation. Recall that I have a Painless kit that I will be using. There is a 4 gauge wire that runs from the alternator to the mega fuse and then to the battery side of the starter solenoid. I'm not seeing that in your schematics. Instead, I see the Blk/O wire or shunt. So, will I not be using the 4 gauge wire from the alternator?  

[Gary Lewis]

Well, you've pointed out another change I need to make - remove the wire color designation.  In fact, I think I typed something about that somewhere, but I don't remember where.

Anyway most, but not all, Ford 3G harnii have a BK/O wire from the alternator.  But some are yellow, and the one from Painless is whatever color.  But the color doesn't matter.

In your case you should use the one from Painless.

[JimsRebel]

Voltmeter Source:
When I wired my voltmeter I had an extra KEY ON wire left over from my DS2 conversion, so I just used it.

This was not something I spent a lot of thought on, it was just quick and simple. I also am not trying to say my way is better. It is really a reflection on how I am ... cheap, lazy, use what you got and never spend a dollar. I am also happy to live in the "good enough" category. That said, I wanted to share what I learned while driving the truck this way the last 6 years.

If I run the power windows you will see a voltage drop on the voltmeter. For me, this is just good troubleshooting info. It tells me the window motor is drawing a normal amount of current.

While at a stop light, you can see a little movement of the needle with the brakes ON-OFF. Nice to know the brake lights are working .

I have headlight relays so I don't see much usable info here. The Heater Fan is a high load of the fuse box and will draw the needle down, say 100% to 75% with fan on high, but I rarely use it on high. But if I find the need to see what the ALT is sending to the battery I can just turn off the heater and the needle jumps back up.

If my ALT had a hard failure my needle would drop from 100% to below 50%. Using a stator relay it would drop from 100% to zero. If you didn't notice a 50% drop would you notice a 100% drop? Is the relay worth the extra complexity?

Regarding a 2G to 3G conversion WITH AMP METER: I would say just cap off the amp meter wires until you can change out the amp meter to a volt meter.

Again, these a just my thoughts and my personal experiences to add to the pool of info, to get to the final product.

Jim #2

 

[ArdWrknTrk]

It's interesting you note that a converted ammeter only has a representative scale and not an absolute scale.
So, if going from 14.3 to 12.7v represents 50% of scale it should be fairly obvious to someone who actually keeps an eye on their gauges.
That you're seeing ~50W deflection when you tap the brakes tells me more than I want to know about the harness.
I guess my brain falls back on familiarity with a power supply or something where you have a lot of scale before the needle even reaches 13v

The whole "all for one, one for all" mindset is a good example of exactly why RJM or Painless have a kit and not enteryouruniversallyfitseverythingbutgoodfornothing

But yeah, my reply to John was absolutely "it's already there and just fine for this"

[JimsRebel]

The Rocket Man Volt meter has a range of 11.5 - 14.5 volts. I have no clue how he did this, I am not that smart.
Here is a link with info.
https://www.ford-trucks.com/forums/1339746-how-to-swap-amp-meter-to-volt-meter.html#post14720315

Jim #2

[ArdWrknTrk]

It is my understanding that the conversion can be done with the ~3V range set wherever you like.

As I said above, I have to defer to someone who has one.
I learned of this guy from an old XR-7 buddy of mine.

[kramttocs]

That is correct. I sent him the specs provided with my alternator when he did mine and he set the values to:

14.8 @ 3/4 setting.
~13.5 @ 1/2 and 12 @ 1/4 so probably about 12.7 @ 3/8.

[Machspeed]

ArdWrknTrk wrote

My regulator pigtail has little raised LSA molded on it.
But I don't know where Painless might source their parts, so have a look when you can?

Jim, you asked me if the pigtail had LSA molded on it. All I see is ASI. I did not pull it to check the other side though. According to Painless, this is what I need for a 3G conversion. Again, it is very high quality as compared to the other pigtail I have.

Regarding the secondary color markings on some of the wires on my alternator harness, there are none on the three yellow wires, nor is there another marking on the red wire. I've been up every inch of the wires. See photo  

[ArdWrknTrk]

I'm thinking 'LSA' must be auto corrected.  
I really need to read it out before clicking "post message"

What I cared is the wires are labeled on the pigtail, but it seems you only have them tagged on the regulator?

[Machspeed]

ArdWrknTrk wrote

I'm thinking 'LSA' must be auto corrected.  
I really need to read it out before clicking "post message"

What I cared is the wires are labeled on the pigtail, but it seems you only have them tagged on the regulator?

That's funny!

[Gary Lewis]

Ok, Jim (the self-ascribed "Jim #2) has made a good case for the simple approach of using some form of switched power for the voltmeter.  So we need to include that approach in our bag of tricks.

And, I'm thinking that we may want to have a tab for Other Options, or somesuch.  On it we could show other approaches but not flesh them out as thoroughly as we need to do for the other, recommended approaches.