3g or large case 1g, which one?

[7.3shrk]

Hey guys,

My truck currently has a 1g alternator. I still have the 3g set up I put on and then took off my other truck before I sold it. I also have access to a large case 1g. My question is, which should I go with? I have searched, but it seems to be like a Ford versus Chevy debate where you have some real distinct opinions. Either one should be relatively bolt in, but I was wondering what the pros and cons would be between the two, and which would be best for my application.

Thanks,

Nick

 

[LCAM-01XA]

3G will give you more power overall, so if you have things like big light arrays or electric winches or such you're probably better off with a 3G. I see you have a 5-speed so the power draw normally associated with the E4OD is not there in your truck, so all your current draw is for the FSS and lights and radio, and maybe an e-pump if you have one - in which case a 1G will work just fine... Your call, I personally went 3G cause of all my lights and stuff.

 

[Agnem]

I prefer an external voltage regulator to an internal one. Easier to troubleshoot when you have a problem. So the 1G would be my preference from that standpoint.

 

[Optikalillushun]

3Gs VR is mounted on the cash, easy and cheap to replace if needed but i havent seen one fail yet from just age.

 

[MIDNIGHT RIDER]

I thought these trucks came equipped with a large-case 1G.


My truck has about as many electrical goodies as one could want, plus many many lights on both truck and lonnngggg trailer, and my old original 1G stood up to the task quite well and was still going strong when I removed it in lieu of a 110-555 160-amp Leece-Neville; although, once off the truck, spinning the pulley sounds like shaking a box of rocks, so I don't know just how much longer that old soldier was gonna stand the racket.


I highly recommend rebracketing to a Leece-Neville, as they are supreme in my opinion and available everywhere.


One thing that I really noticed when I removed the old 1G is how tiny small the factory-issue charge-wire is; I don't see what keeps it from melting under load.


In comparison, the Leece-Neville has a big old 2/0 charge-wire and an equivalent GROUND; overkill, I know, but it is what I had hanging on the wall, so it is what got used.

 

[Matrix37495]

Midnight, do you have more info on your alt? Maybe pics of the modified mounts?

 

[LCAM-01XA]

I thought these trucks came equipped with a large-case 1G.

Yup, they sure did.

My truck has about as many electrical goodies as one could want, plus many many lights on both truck and lonnngggg trailer

I have over 1kW of lights on mine tho, plus it's a slushbox so that hogs another like 20 amps right there, and I have a power inverter in the cab. I needed more than 100 amps with all this, there was no ifs ands or buts about it.

One thing that I really noticed when I removed the old 1G is how tiny small the factory-issue charge-wire is; I don't see what keeps it from melting under load.

The charge wire can be upgraded, and IMHo should be regardless of alternator used. I use a 1/0 welding cable pumping straight into the battery, all my high-power loads are wired straight to the batteries as well - really the only thing that runs off the starter solenoid on the fender is the cab/dash power and the E4OD stuff, which is nothing really compared to the rest of the stuff I got. Also the Ford alternators ground through the case, so no external ground is needed in 99% of the time, altho I know of at least one case where adding a separate ground from the alt to the battery directly fixed a low-charge issue...

 

[typ4]

Well leece-neville used to be good, now theye are made by prestolite, and the only place to get one is a big truck store if you are on the road, I can tell you they are not available everywhere, I had one took it off after it crapped in canada and couldnt find one anywhere,including several electric shops, just my opinion

 

[Dave7.3]

On the topic of the 3G alternator...how would you wire it to bypass the external voltage regulator? I know there is a write-up somewhere but the forum search isn't pulling anything up for me.

My truck has a rebuilt 100amp 1G alternator that the PO installed and it works great...but I am curious to see how one of those 3G bad boys would do...

 

[MIDNIGHT RIDER]

Midnight, do you have more info on your alt? Maybe pics of the modified mounts?

Unless you also have a 6BT Cummins in your truck, pictures of my mounts would be of little help.

However, there are some on here with IDIs and Leece-Nevilles; maybe they will post up some pictures.

Just about any decent truck-stop will carry a few replacements, as they are under the hood of just about every big truck on the road.


http://www.prestolite.com/pgs_products/specs.php?item_detail_id=25083&item=8LHA2071VA



Once you get brackets made to fit, then any J-mount alternator will bolt up; it does not necessarily have to be a Leece-Neville; although, they are the most common.

 

[7.3shrk]

Thanks guys, I upgraded to a different truck - a CC 4wd 1985 dually. This one has a slushbox (going to be an E40D eventually). really have no problems with the truck as it is and have no power accessories, and my biggest draw is going to be the lighting. I am going to be upupgrading and addint lighting and other stuff eventually. How do you identify the different large case 1g's? Are there differences in power output?

 

[LCAM-01XA]

there's a 70-amp or 75-amp 1G, and there is also a 100-amp 1G, take a look here for pics of both:
http://fordfuelinjection.com/?p=63

Nice choice of a new truck by the way, what lights and how many you plan on installing?

 

[typ4]

I have a large case 1g 100 amp off a 25k mile motorhome , make you a smokin deal on it, and I could do a diode plate upgrade to make it virtually bulletproof.

 

[MIDNIGHT RIDER]

there's a 70-amp or 75-amp 1G, and there is also a 100-amp 1G, take a look here for pics of both:
http://fordfuelinjection.com/?p=63

Nice choice of a new truck by the way, what lights and how many you plan on installing?

I am almost certain that the originals on the early IDI trucks were 90-amp.


Before I became a Leece-Neville convert, I picked up every reasonably-priced (cheap) large-case 1G that I saw at swap-meets, just to have plenty of spares laying around and for maybe disecting and "improving" once I learned how.

I have bought good working ones for as little as a buck; I never paid more than five for one.

At one swap-meet, there was a guy who was clearing out his deceased neighbor's meticulously-rebuilt/repainted alternators and starters as a favor to his widow; everything the guy had rebuilt was painted a bright gold; I took every 1G that he had.

 

[7.3shrk]

I got offered the 1g and am figuring it would be an upgrade as it was for a high electrical draw fleet truck over the one I have now. Like I said, I was just curious since I have access to both for little to no cost.

As for lighting, I am not sure yet, I am going to add auxilliarl back up lights, BUT everything else will SLOWLY have to just appear subtly on the truck as to not raise suspicion with the wife......