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12 volt conversion question

S

SteveB(OH)

Member
Hi all,

I'm almost afraid to bring up this hotly debated topic :lol: :lol:

I am planning to upgrade my 48 front mount 8N to 12 volts.

I'm looking at the kit offered on this site and I notice that it includes a one wire alternator. Other posts that I have read on this forum indicate that a one wire alternator requires high engine revs to excite it and get it charging. The 3 wire 10SI seems to avoid that problem.

Then I read the FAQ for the kit on this site and found this:

Q. Do I need to run the engine at full throttle to make the Alternator charge the battery?

A. Absolutely not. The first time you start up your newly converted system, you may have to run the RPMs up to help the self-exciting alternator/regulator begin to charge. The characteristics of a generator are such that they do not charge at low-idle and the charge tends to fall off at high-RPM. This is not so with an alternator and indeed was the reason that alternator became the standard in the 60s. The alternator will deliver a healthy charge throughout the RPM band of your tractor.

I'm confused about that statement. When they say "first time" does that mean that once I've revved the tractor after the conversion I'm good to go forever, or do I have to rev it high every time I start it and then I'm good until I shut it down ?

If it's the latter I'll look for a 10SI.

Thanks,

-Steve
 

i have a one wire alternator on mine, and i have never had to do anything out of the ordinary. it charges my battery without jumping thru any hoops that i'm aware of.
 
They mean the first time you start it most every day.
But, don't think you have to rev the bejeebies out of it either.
All you have to do is get it over a fast idle, maybe 900 RPM or so.
Then, once they have started charging, they will normally charge below that.

I wire all of mine with the three wire alternators and I have
one (just one) three wire that acts the same exact way.
I have to get it above 1000 RPM for it to start charging.
The reason? It has a half inch pulley and belt instead of the
correct 5/8 pulley and belt. So the belt slips a bit when cold.

You need the correct belt and pulleys with either one.
 
I got the kit last year and put it on one of my 8ns, I have never been happier and find the the one wire works great and with out all the added diode bs. The mount bracket worked just great. No high revving to make it charge either.
 
"I'm looking at the kit offered on this site and I notice that it includes a one wire alternator. Other posts that I have read
on this forum indicate that a one wire alternator requires high engine revs to excite it and get it charging."

Not true. Starts charging immediately.
 
Yes, it is confusing and written by someone who does not understand electronics.

The way those 1 wire works, is they need high rpm to self excite.

3 wire excite at a much lower rpm, often at around 400 rpm.

Once excited, either alternator will charge while running down to about 400 rpm, and up in rpm past what the tractor can do.

Once you shut the machine down, you start all over again. the 3 wire auto self excite, the 1 wire need the rpm pump real quick
to self excite.
 
OK, then what do you call high rpm to excite? I start about 1/3 throttle and it starts charging straight away. I do not call that high rpm.
 
3 wire jobs will charge at pretty much the lowest idle you can get an N to make.

1 wire jobs? depends on the vreg module they have used. I've seen everything from 600-750, to 900-1200.

I was helping a guy put a 1 wire ( his choice ) on his JD B. the B couldn't get the alt to excite at just over 900 rpm.

In general, 1 wire jobs cost more than 3 wire.

Why pay more? Methinks plenty of people are afraid of another 3' of wire and a light bulb...

Might be easier to understand by saying 'High-er' rpm to excite. How high? depends on the specific vreg module used, and
what pulley you have.
 
[b:d1f00d57f0]
"I start about 1/3 throttle and it starts charging straight away."[/b:d1f00d57f0]

same here. i had reason to pay attention this spring, as i forgot to tighten the nut on the 1 wire on the back of the alternator after tearing everything apart for a rebuild. when i realized it, and tightened the wire down, i made a point of watching the ammeter, which jumped up as soon as the tractor started, which was at about 1/3 throttle. i can't imagine ever firing the N up and having less throttle, not sure what i'd do with it running any slower.

as for why i ended up with it to begin with, it wasn't a decision to save wire or avoid light bulbs and/or diodes. i had no idea of any of these details at the time, i simply bought the conversion kit my local tractor dealer was selling, and that's what was in it.
 
(quoted from post at 09:08:51 11/08/16) 3 wire jobs will charge at pretty much the lowest idle you can get an N to make.

1 wire jobs? depends on the vreg module they have used. I've seen everything from 600-750, to 900-1200.

I was helping a guy put a 1 wire ( his choice ) on his JD B. the B couldn't get the alt to excite at just over 900 rpm.

In general, 1 wire jobs cost more than 3 wire.

Why pay more? Methinks plenty of people are afraid of another 3' of wire and a light bulb...

Might be easier to understand by saying 'High-er' rpm to excite. How high? depends on the specific vreg module used, and
what pulley you have.
Click to expand...

So I read this and figured what the heck, I'll do the 3 wire conversion. Surprisingly enough, it would cost me more to buy a 3 wire alternator at Autozone ($57.00) and mounting brackets plus a pulley from YT ($44.90) than it would cost to simply buy the kit.

I appreciate all the insight from everyone and I'm more educated now than I was, but it sounds like the 1 wire will work, so I will probably do that.
 
Kit form is what gets you.

The 3 wire alternators are as low as 29$ ( with core ). Single wire alt's are more $$

Brackets: many of them make them ourselves.

Pulley: Local for a looooooooot less than 45$
 
The kit was simple to install. I did not have to shop around for the cheapest alt and pulley and then rewire to make it work. Package deal, everything I needed delivered to my door and install and running an hour or so later.
Each to his own.
 
Hey man.. your autozone is ripping you off.

they are 31.99$ at autozone ( 7127 alternator )63 amp
 
I'm not going to take bidness away from this site.. however.. thair bracket kit here plus pulley is only 45$... alts are 32$ ..
everywhere. marker lamp is 1-2$.... your existing wire harness with wiring for your generastor already has enough wires in it
to wire up the non kit. ;)
 
(quoted from post at 11:28:00 11/08/16) Hey man.. your autozone is ripping you off.

they are 31.99$ at autozone ( 7127 alternator )63 amp
Click to expand...

$31.99 + $15.00 Core = $46.99 out the door for me.

The price I originally mentioned was for a 7127-9 which was specifically recommended in another post on this site because it was a "9 o clock" orientation.

So bottom line, if I make my own brackets I could get the job done for $69.37 ($46.99 for alt + $22.38 for pulley (YT Store with shipping) = $69.37

I can buy a kit for $98 delivered (not YT). So the difference would amount to $28.63

Since others report that the single wire works well I question if its worth $28 to drive to the auto parts store and fab up my own brackets.

Don't get me wrong, I appreciate your help, just weighing options.
 
One reason I stick with a 3 wire is that when the alt needs replacing I can buy a cheap rebuild alt off the shelf at any autoparts store for $30 while a one
wire usually means buying from a speciality vendor on the net which in turn means delay and shipping charges.,and probably higher price if you are not
buying a whole kit.
 
One other minor point.

The brackets for a front mount are VERY easy. just the top bar really, and then 2 short pieces of stock drilled for 2 holes
each... mount governor to lower alternator ear. top bracket.. universal job even works from the auto store.. or, again..
flat stock and a few holes drilled... attached to a water pump bolt.

On a sidemount.. you can use the existing genny base, and again.. that universal top mount bar.

Bottom line.. if you own a hacksaw and drill, and possibly, if you want to get fancy, a welder, brackets aren't anything that a
few minutes with a measureing tape and some arm movement won't solve...

Again.. just putting that out there.

I know some people like to open one box and install stuff from one source vs opening 2 boxes, or making a part.. and that's
cool too. The people that sell the kits need bidness too!
 
Hi everyone,

I started the conversion today and I have a question for you.

The upper mounting bracket in the kit is designed to be mounted under the front 2 head bolts.

Yikes, I sure don't feel like removing 2 head bolts. I replaced the head gasket 15 years ago and it has been trouble free since then.

Am I tempting fate by removing 2 head bolts ?

I don't see any other good options for the upper bracket. I looked at the water pump and the fastener on the alternator side is a stud that is no longer than the nut, I don't see that as a good option.

Thanks as always for your help !
 

[i:ad09325aaa][b:ad09325aaa]"Am I tempting fate by removing 2 head bolts ?"[/b:ad09325aaa][/i:ad09325aaa]

not unless u don't intend to put them back in and torque them down again ;)

mine worked the same way, had no issues with head gasket. 3 or 4 years later, i rebuilt the engine. the head gasket was still fine.
 
UPDATE:

I got the conversion done today and I'm quite pleased with it:

Alternator%201.jpg


I even got fancy and installed a fuse block for power distribution:

Alternator%202.jpg


Concerning the original question about when the alternator starts charging I'm happy to report that there is no problem. It is POSSIBLE to start the tractor at such a slow idle speed that the alternator doesn't cut in, but I was only able to make that happen after the engine was warm, and I have never purposely started it that slow before. Under normal conditions it starts charging immediately. Even when I started it at dead slow, by the time I raised engine speed enough to back out of the barn it started charging.

I'll be happy so long as my head gasket doesn't start to leak... :(
 

That is a waterproof marine grade toggle switch that I installed after the key switch was suspect. I did that years ago.
 
(quoted from post at 17:58:27 11/26/16) You are a Voltmeter away from have a nice set up...
Click to expand...

Agreed, I would take a voltmeter over an ammeter any day. I doubt I'll bother with it in this case though...
 
"You are a Voltmeter away from have a nice set up..."

Be a little more forthcoming Hobo.
You like the voltmeter set up over the ammeter setup.
We know that. I have both and my jury is still out on the subject.
But, the man can't just swap a voltmeter in place of his ammeter.
Not that the re-wire is difficult at all, but not a direct swap.
 
(quoted from post at 23:11:31 11/26/16)
That's what you get when you pick a jury from folks that hang out at Walmart.
Click to expand...
As you (should) know, you don't pick your own jury.
If you are inferring that a jury of my peers would come from Walmart,
then that's a misunderstanding on your part.

Voltmeters still do not directly swap with an ammeter wiring wise.
If you want to suggest swapping them, I suggest posting links
to wiring diagrams that show how to do so. Or at least instructions.
Before someone burns up their money doing it the wrong way.
 
It would take the fun away from amp meter lubbers that have yet to get a handle it.

Your jury is lost in time...

How many pages of poor advice does it take before someone gets lucky are someone ask "whats the voltage reading"



http://forums.yesterdaystractors.co...postorder=asc&highlight=hole&start=60

Everything I have done to this tractor in this long and painful process was at the strong recommendation of this forum. The last thing I wanted to do was replace good parts or waste my time.


I know advice is offered as good will but damm how long will it take before the jury finds out the magic a voltmeter reading provides.
 
"Your jury is lost in time... "

Is THAT where they are?!?!?
Well, at least it keeps me from being convicted. :lol:

Here's JMOR's pictogram for a late 8N 12V conversion with a
voltmeter. I have a few wired by his diagram and the work very
well. It also works well for the Jubilee/NAA and hundred series.

I know that because I have all of those wired with voltmeters.
If someone wants to wire one with a voltmeter, this is a good
example of how it is supposed to be wired.

42927.jpg
 
This subject always amuses me. Lets see. I start something. The amp meter shows amp draw when cranking then jumps up to a 15-20 amp charge and starts dropping telling me A: amp draw when cranking B: that the charging system is working. C: that the battery is taking a charge. A volt meter tells me how much charge is in the battery before starting, how much voltage drop I get when starting and then shows me the battery/charging system voltage.

Now I have a battery load tester. So either gauge works for me. I have both and I really prefer the amp meter. Load tester was cheaper than converting 8 or 9 pieces of equipment and can be tossed in a tool box and hooked up to anyones equipment or vehicle so I go to help someone out. Battery load tester seems to be the way to go. It tells me the condition of the battery and if the charging system is working. So if you really want to talk diagnostics a battery load tester and multimeter is the way to go unless of course it's computerized then a scan tool. Got one of those too.

Rick
 
(quoted from post at 00:39:57 11/28/16) This subject always amuses me. Lets see. I start something. The amp meter shows amp draw when cranking then jumps up to a 15-20 amp charge and starts dropping telling me A: amp draw when cranking B: that the charging system is working. C: that the battery is taking a charge. A volt meter tells me how much charge is in the battery before starting, how much voltage drop I get when starting and then shows me the battery/charging system voltage.

Now I have a battery load tester. So either gauge works for me. I have both and I really prefer the amp meter. Load tester was cheaper than converting 8 or 9 pieces of equipment and can be tossed in a tool box and hooked up to anyones equipment or vehicle so I go to help someone out. Battery load tester seems to be the way to go. It tells me the condition of the battery and if the charging system is working. So if you really want to talk diagnostics a battery load tester and multimeter is the way to go unless of course it's computerized then a scan tool. Got one of those too.

Rick
Click to expand...
Yep, I have both too. I haven't decided which I prefer.
In either case, the in-dash gauge isn't the end of diagnostics.
 
Kinda like Bourbon and Scotch........some prefer one, some prefer the other.........choose your poison.
 

No its not... Folks would have a better chance of helping with others problems if they would just ask "WHATS THE VOLTAGE" Lack of having a voltmeter is not a valid excuse. Not checking voltage are not asking dumbs down the community as a hole.
 
(quoted from post at 10:39:57 11/28/16) This subject always amuses me. Lets see. I start something. The amp meter shows amp draw when cranking then jumps up to a 15-20 amp charge and starts dropping telling me A: amp draw when cranking B: that the charging system is working. C: that the battery is taking a charge. A volt meter tells me how much charge is in the battery before starting, how much voltage drop I get when starting and then shows me the battery/charging system voltage.

Now I have a battery load tester. So either gauge works for me. I have both and I really prefer the amp meter. Load tester was cheaper than converting 8 or 9 pieces of equipment and can be tossed in a tool box and hooked up to anyones equipment or vehicle so I go to help someone out. Battery load tester seems to be the way to go. It tells me the condition of the battery and if the charging system is working. So if you really want to talk diagnostics a battery load tester and multimeter is the way to go unless of course it's computerized then a scan tool. Got one of those too.

Rick
Click to expand...

"Lets see. I start something. The amp meter shows amp draw when cranking then jumps up to a 15-20 amp charge and starts dropping telling me A: amp draw when cranking B: that the charging system is working."

A: A in dash amp meter can not display starter amperage.
B: You can have amps but low voltage that is not gonna keep your battery charged and healthy. A charging system on its way out can still output amps. I slipping belt will still show amps the voltage reading will tell the story it will always be low on a inefficient charging system.

"A volt meter tells me how much charge is in the battery before starting, how much voltage drop I get when starting and then shows me the battery/charging system voltage."

No magic in that quot you did not have to make up a excuse like folks that base there diagnostic approach using a dash mounted amp meter.

Day to day use just take a quick look at the voltmeter if the output is in the 14V range NO chiffering needed. There was a post 3/4 months ago were a guy had a high amperage reading he was lead on his alt was bad in the end when he drug out a voltmeter (yes that was hard ha ha) he had a low battery
:shock: If he are those trying to help would have just asked "WHATS THE VOLTAGE READING.

Can someone splain to me what is so dang hard about taking a volt reading does it hurt that bad. Are you so consumed with that little amp meter that you base all your diagnostic ability's on that little amp meter. I would think as well educated as some are here you would want to gather as much information as you can before you offer a battle plan.

Clean bright and tight that's always good good but it will never replace the information needed to make a valid diagnosis. Its just a excuse to hide behind and I guess it is if you base it on a little in-dash amp meter.

This is the post "Hung up on AMPS" There was nuttin wrong with it other than folks fell into the amp meter trap...

http://forums.yesterdaystractors.co...&postdays=0&postorder=asc&start=0
 
(quoted from post at 06:38:22 11/28/16)
(quoted from post at 10:39:57 11/28/16) This subject always amuses me. Lets see. I start something. The amp meter shows amp draw when cranking then jumps up to a 15-20 amp charge and starts dropping telling me A: amp draw when cranking B: that the charging system is working. C: that the battery is taking a charge. A volt meter tells me how much charge is in the battery before starting, how much voltage drop I get when starting and then shows me the battery/charging system voltage.

Now I have a battery load tester. So either gauge works for me. I have both and I really prefer the amp meter. Load tester was cheaper than converting 8 or 9 pieces of equipment and can be tossed in a tool box and hooked up to anyones equipment or vehicle so I go to help someone out. Battery load tester seems to be the way to go. It tells me the condition of the battery and if the charging system is working. So if you really want to talk diagnostics a battery load tester and multimeter is the way to go unless of course it's computerized then a scan tool. Got one of those too.

Rick
Click to expand...

"Lets see. I start something. The amp meter shows amp draw when cranking then jumps up to a 15-20 amp charge and starts dropping telling me A: amp draw when cranking B: that the charging system is working."

A: A in dash amp meter can not display starter amperage.
B: You can have amps but low voltage that is not gonna keep your battery charged and healthy. A charging system on its way out can still output amps. I slipping belt will still show amps the voltage reading will tell the story it will always be low on a inefficient charging system.

"A volt meter tells me how much charge is in the battery before starting, how much voltage drop I get when starting and then shows me the battery/charging system voltage."

No magic in that quot you did not have to make up a excuse like folks that base there diagnostic approach using a dash mounted amp meter.

Day to day use just take a quick look at the voltmeter if the output is in the 14V range NO chiffering needed. There was a post 3/4 months ago were a guy had a high amperage reading he was lead on his alt was bad in the end when he drug out a voltmeter (yes that was hard ha ha) he had a low battery
:shock: If he are those trying to help would have just asked "WHATS THE VOLTAGE READING.

Can someone splain to me what is so dang hard about taking a volt reading does it hurt that bad. Are you so consumed with that little amp meter that you base all your diagnostic ability's on that little amp meter. I would think as well educated as some are here you would want to gather as much information as you can before you offer a battle plan.

Clean bright and tight that's always good good but it will never replace the information needed to make a valid diagnosis. Its just a excuse to hide behind and I guess it is if you base it on a little in-dash amp meter.

This is the post "Hung up on AMPS" There was nuttin wrong with it other than folks fell into the amp meter trap...

http://forums.yesterdaystractors.co...&postdays=0&postorder=asc&start=0
Click to expand...

What about folks who fall into that volt meter trap when all they really need is a little red light?

OK so a volt meter can show me pre start battery voltage. SO what? Without any meter I can turn the key/hit a button and find the same thing! That meter isn't going to tell me why it may have low voltage, only what the starter relay "click" will tell me. And a battery as my load tester shows may show 12+ volts and still be bad! So the meter didn't tell me anything and the "click" did! Lets see, it the alternator starts to overcharge ethe battery while running the meter will tell me that. Same as an amp meter when all of a sudden it starts showing a higher rate of charge. But with the amp meter knowing that it's charging at a high rate still may tell me other things like besides a possible VR issue. Like something in the system causing it to charge at a higher rate like a short. And once I turn the key off why would I check post run voltage? The only vehicles I've seen with a battery/voltage gauge where there is a real reason to have one is military vehicles that sit, engine off, night sights, ballistic computers and electric driven hydraulics plus radios on. There the driver can tell the vehicle commander when the vehicle needs to be started to recharge that batteries. WE used them religiously on the tanks! THEY STILL HAD AN IDIOT LIGHT for the charging system! Another one for engine systems malfunctions! And the mechanics never ever used the volt meter to try to diagnose low voltage problems! In fact you are the only person I have ever heard say that you can.

Rick
 
Rick,you hit the nail square on the head. These tractors aren't very complicated. The knowledge of ohm's law is all you need. As far as vom over ammeters,it's all related to your trouble shooting skills and which component you're looking at. Both have their place.The simplest way to explain it is this.You can read battery voltage across the terminals being 6 or 12v without having the current required to crank the starter motor.That was the whole reason in creating the multi-meter.It sure saves a lot of time. mike
 
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