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10/12/2022 9:34 PM  #1


3g one wire alternators

which ones and where did you get yours?


Its really me....I fixed my caps lock .
 

10/13/2022 4:57 AM  #2


Re: 3g one wire alternators

No one wire alternators, EVER.  Do a proper install where the alternator can "see" feedback and adjust output accordingly. 

 

10/13/2022 6:42 AM  #3


Re: 3g one wire alternators

I bought a Bosch unit from Rock Auto for a 95 Mustang with a 5.0. Part number AL7534N. 

It's not a one wire alternator. You need a plug in pigtail to go with the power connection. I sourced it from the local pick a part. You should be able to but it new. 

What are you doing for belts? I could never get it tight enough with the typical alternator V belt pulley. Bought a Hi-Po pulley through Steve Buzek. Had to have some machining done to get the clearance I needed for the back side and a full nut to secure it. It's been good ever since. 

         

   

    

    

 


John  -- 67 Mustang Coupe 390 5 speed
 

10/13/2022 10:51 AM  #4


Re: 3g one wire alternators

Billy - When installing a modern alternator care must be taken to properly protect the car’s circuits.  Original alternators put out like 40 amps, modern alternators put out significantly higher amperage, like 150amps.  Without including the protection (fuses/circuit breakers) found in the modern cars, one could cause a fire if a short circuit, or other failure, were to occur. 
 
Bolted to Floor – I found that I had to use a ½” wide V-belt for the alternation rather than to original 3/8” wide belt.  I believe this is because, while it is sold as a 3/8” belt, it is really a slightly smaller width made to metric sizes.  Anyway, the ½” belt stopped the belt squealing I was getting with the “3/8” belt.


65 Fastback, 351W, 5-speed, 4 wheel discs, 9" rear,  R&C Front End.
 

10/13/2022 6:13 PM  #5


Re: 3g one wire alternators

With 289, I ditched the 1G and installed a 10si one wire 100 amp alternator.
Purchased from Fleet Farm.

It was more than enough to keep the battery charged and run my entire car.

My stock 65 Mustang wire harness had absolutely no form of fuse or fuse link.
The wire runs from start solenoid to the fuse box.

The regular 3 wire 10si alternator is just as simple to wire in a similar fashion.

Now…here’s the catch…both of these alternators require the pivot hole drilled out to reuse the factory alternator bolt.
I didn’t like the smaller diameter bolt that GM used.

With the 5.0L, I am now using a 3G alternator (130 amp) in the 92 Mustang accessory drive.
This is NOT a one wire alternator.
Purchased at Fleet Farm too.
The wire harness is from a 2001 v6 Mustang…it has factory fuse links connecting to the start solenoid.

3G alternator is common on many Ford products.

 

10/14/2022 8:36 AM  #6


Re: 3g one wire alternators

I upgraded to a ford, 5.0 compatible, 3G alternator when I relocated my battery to the back.

1966 Mustang Coupe, 5.0 Swap, EFI

 

10/14/2022 4:00 PM  #7


Re: 3g one wire alternators

Nos681 wrote:

With 289, I ditched the 1G and installed a 10si one wire 100 amp alternator.
Purchased from Fleet Farm.

It was more than enough to keep the battery charged and run my entire car.

My stock 65 Mustang wire harness had absolutely no form of fuse or fuse link.
The wire runs from start solenoid to the fuse box.

The regular 3 wire 10si alternator is just as simple to wire in a similar fashion.

Now…here’s the catch…both of these alternators require the pivot hole drilled out to reuse the factory alternator bolt.
I didn’t like the smaller diameter bolt that GM used.

With the 5.0L, I am now using a 3G alternator (130 amp) in the 92 Mustang accessory drive.
This is NOT a one wire alternator.
Purchased at Fleet Farm too.
The wire harness is from a 2001 v6 Mustang…it has factory fuse links connecting to the start solenoid.

3G alternator is common on many Ford products.

I also installed a GM 3-wire 10SI alternator in my 65, purchased from a local rebuilder, and drilled the pivot hole to use the original small block engine’s 7/16” pivot bolt.  This alternator’s tested output was about 70 amps, and I am happy with it, although I do not have any high-powered accessory equipment.  I’ll add that the internal voltage regulator did fail after several years, it was an inexpensive (like $10) and an easy replacement.  

 


65 Fastback, 351W, 5-speed, 4 wheel discs, 9" rear,  R&C Front End.
 

10/14/2022 9:18 PM  #8


Re: 3g one wire alternators

My 66 has a 3g alternator with sensor wire. Works great. A little belt squeal at start but never while running. March aluminum crank pulley, stock water pump pulley and steel 289 hipo alternator pulley.

My 69 has a one wire alternator with multi rib serpentine belt. Charges the car just fine. Gauge reads about 14 volts no matter rpm.


Money you enjoy wasting is NOT wasted money... unless your wife finds out.
 

10/15/2022 9:28 PM  #9


Re: 3g one wire alternators

The best thing about a 3g is it's sensing ability. I think the regulator detects the voltage drop from the starter, and tries to replace it with 130+ amps, straining a single v-belt.
The white regulator for a 3g has a 2.5 second LRC (Load Response Control) delay. Which should not "see" the voltage drop. I've never tried one as I have a serpentine belt setup. There is also a black regulator with a higher LRC.
This is all theory on my part. Never had to test it.
https://store.alternatorparts.com/f795-3g-series-12-volt-internal-voltage-regulator.aspx

Last edited by 50vert (10/15/2022 9:30 PM)


"Those telephone poles were like a picket fence"
 

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