TheAMCForum.com Homepage
Forum Home Forum Home > The Garage > Electrical - non engine
  New Posts New Posts RSS Feed - one wire alternator
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

Click for TheAMCForum Rules / Click for PDF version of Forum Rules
Your donations help keep this valuable resource free and growing. Thank you.

one wire alternator

 Post Reply Post Reply Page  <12345 6>
Author
Message
vinny View Drop Down
Supporter of TheAMCForum
Supporter of TheAMCForum


Joined: Jan/05/2012
Location: Calgary
Status: Offline
Points: 2837
Post Options Post Options   Thanks (0) Thanks(0)   Quote vinny Quote  Post ReplyReply Direct Link To This Post Posted: Oct/01/2017 at 10:42am
I think rather than go backwards use the CS series. The light goes out before the car starts which shows the lower speed charging is better and they are very common and easy to replace. They changed out the SI series for a reason.

I had a 10si on a 232 but removed it because the light would come on at low idle. It works fine on my truck but I think the crank pulley on it is bigger.


Edited by vinny - Oct/01/2017 at 10:46am
Back to Top
amcfool1 View Drop Down
AMC Addicted
AMC Addicted
Avatar

Joined: Jun/18/2011
Location: roanoke va
Status: Offline
Points: 1071
Post Options Post Options   Thanks (0) Thanks(0)   Quote amcfool1 Quote  Post ReplyReply Direct Link To This Post Posted: Oct/01/2017 at 12:04pm
billd, thank you for your response, I will go with the 12si. thanks, gz
george z
Back to Top
billd View Drop Down
Moderator Group
Moderator Group

Forum Administrator

Joined: Jun/27/2007
Location: Iowa
Status: Offline
Points: 30894
Post Options Post Options   Thanks (0) Thanks(0)   Quote billd Quote  Post ReplyReply Direct Link To This Post Posted: Oct/01/2017 at 12:58pm
Originally posted by vinny vinny wrote:

I think rather than go backwards use the CS series. The light goes out before the car starts which shows the lower speed charging is better and they are very common and easy to replace. They changed out the SI series for a reason.

I had a 10si on a 232 but removed it because the light would come on at low idle. It works fine on my truck but I think the crank pulley on it is bigger.


That's not typically why the light goes out............... it's not low speed charging that does that. 

A light coming on at idle indicates some other form of problem, not lack of slow speed charging. Been at these for over 40 years. The problem is that when people don't know the facts all sorts of things start to circulate. 
Back to Top
vinny View Drop Down
Supporter of TheAMCForum
Supporter of TheAMCForum


Joined: Jan/05/2012
Location: Calgary
Status: Offline
Points: 2837
Post Options Post Options   Thanks (0) Thanks(0)   Quote vinny Quote  Post ReplyReply Direct Link To This Post Posted: Oct/01/2017 at 10:26pm
Well then what puts out the light if not alternator RPM coming up to a minimum speed? 10si works fantastic in my truck charging at 14+ volts and light never comes on. In the Rambler the light would only flicker at very low RPM and like I said the crank pulley is smaller. It annoyed me. The CS 130 never does that.

A little history on what I've been doing for fun. Prestolite alternator and regulator had to go. Bearing and brushes shot, regulator very rusted. Tried a Motorola alternator on the rusty Prestolite regulator, surprisingly to me it worked. Saw a 10si on a Jeep 360 at the wreckers with the 1" pivot base. Tried that, light comes on at very low idle, maybe 350-400RPM? Thought it was no good and tried another one, same thing. Then I went to the CS130. Of the five alternators I tried, The Pestolite, the Motorola, 2 10si's, and the CS130, the light only came on with the 10si's.


Edited by vinny - Oct/02/2017 at 7:23am
Back to Top
vinny View Drop Down
Supporter of TheAMCForum
Supporter of TheAMCForum


Joined: Jan/05/2012
Location: Calgary
Status: Offline
Points: 2837
Post Options Post Options   Thanks (0) Thanks(0)   Quote vinny Quote  Post ReplyReply Direct Link To This Post Posted: Oct/02/2017 at 6:51pm
Time to eat some crow. Truck crank pulley and Rambler pulley are the same size at about 6 7/8" I guess I've got the Rambler idle set lower than the truck.
Back to Top
billd View Drop Down
Moderator Group
Moderator Group

Forum Administrator

Joined: Jun/27/2007
Location: Iowa
Status: Offline
Points: 30894
Post Options Post Options   Thanks (0) Thanks(0)   Quote billd Quote  Post ReplyReply Direct Link To This Post Posted: Oct/02/2017 at 6:59pm
Still should not matter unless you have the idle set down to about 300 RPM. Seriously, my bet - something in the wiring, or something changed when swapping things around. 
I've idled engines - yes, AMC engines, down to 500 and not seen the 10si show the light due to speed. Not keeping up with a load yeah - but not a dash light coming on. 
That dash light would go out as soon as there was +12 volts coming at it from the alternator side. 
The regulator, diode trio, wiring, brush and slip ring condition and other factors come into play. A WEAK diode can cause similar issues, depending on the vehicle wiring, battery and so on. Batteries present different loads - or NO load or lack of load, "depending". 
I could get into great detail on the operation of the transistors, internal diodes, the trio, the zener diode, voltage drops at various points, the resistance of the dash ALT light and so on - but it would take more time than the forum would keep my session alive unless I did it in Word or WordPad first and pasted it in. 

Back to Top
vinny View Drop Down
Supporter of TheAMCForum
Supporter of TheAMCForum


Joined: Jan/05/2012
Location: Calgary
Status: Offline
Points: 2837
Post Options Post Options   Thanks (0) Thanks(0)   Quote vinny Quote  Post ReplyReply Direct Link To This Post Posted: Oct/04/2017 at 8:53am
Well I could hold a birthday party for the battery because it is no longer a teenager but I don't think that has anything to do with it. It came from a 98 Ford van built in Oct or Nov of 97 that I had bought  at six months old.

With the 10si's and the automatic it would sometimes go low enough to turn the light on, just dimly, and a touch of the throttle would extinguish it. On start up with the CS130 the light mostly goes out as soon as the key is touched, certainly out before it is even running. That tells me there is nothing wrong with the way it is wired.

The point of all this nitpicking is that I don't think anyone should waste their money converting over to an old alternator (10si) that doesn't perform very well. The same money can buy something better and the time spent is the same for either.
Back to Top
billd View Drop Down
Moderator Group
Moderator Group

Forum Administrator

Joined: Jun/27/2007
Location: Iowa
Status: Offline
Points: 30894
Post Options Post Options   Thanks (0) Thanks(0)   Quote billd Quote  Post ReplyReply Direct Link To This Post Posted: Oct/04/2017 at 10:28am
Batteries DO have something to do with this topic. Batteries age - and that makes a difference on what it takes to charge it, it's resistance in the circuit and more. 
Further, not all batteries are the same even when new. Even GM made changes to their batteries in the 80s sending out bulletins related to difference charging voltages, etc. - and that means they presented different loads to the alternators!

By moving the alternator you made changes you aren't even aware of. Can you state the pulley wrap is identical, the belt grip was identical, the belt tension, belt age or "stickiness" was identical? You moved wire connections and more. 
Sorry, your logic is flawed and based on an alternator move to a different vehicle where you introduced a list of variables too long to get into. You are talking a couple of alternators and a couple of vehicles - and you introduced more changes than you know.

On the other hand, I base things on decades of experience on hundreds of alternators of all types, brands, nationalities and many hundreds of cars from all makes, models, etc. as well as GM factory training, college and HS training, electronics classes and again, a list too long to get into. I also scope alternators........ and get into things even many alternator shops today don't talk about. 
You can't say that tells you there was nothing wrong with the "way it was wired" - and did you know the circuit to the light is broken during cranking in most vehicles? The light will go out while cranking in many cases depending on the car and how things are wired (and of course during cranking you are pulling system voltage down quite a bit, also changing things)
Bottom line - that's very flawed logic and frankly, does anyone care if the light goes out while cranking or waits until the engine is running? Does that matter? (except in cases where there are problems causing the differences)

Explain why going to a 10si or a 12si is a waste of money if you can get one for say ten bucks but another would cost you thirty or forty bucks?
Me - I'd save the money - you have to be kidding that a 40 year old AMC is going to care about the differences.
The 10si will do more than you need IF you are replacing an alternator of the same output. If you swap out a Motorola and swap in a GM alternator of similar output - does it matter if it's the latest GM alternator? Nope - because the 10si will do the job. (not as well as a decent Motorola, frankly)
If a person saves ten bucks using a 10si - who is to say it was a waste? 
Good grief, these are old cars with old wiring, etc. and minimal needs for charging rates.

It's not really an upgrade in any case if the original handled the load (and I will clarify that by saying if the original will handle the load IF THE ORIGINAL WAS FIXED PROPERLY)
Too many call it an upgrade when they take out a WORN OUT barely working alternator and replace it with a working alternator - gee, I just upgraded. No you did not. You could have done the same by having me make your original work like it should. 
To remove an OLD, a forty year old unit and replace it with another then say it was an upgrade or is far better? Really? Give me a shot at the old Motorola, or if you don't like it give it to me! I'll make it keep up with anything else of that era and that's more than enough for most of these cars. 

While I agree if someone insists on doing a swap, do the 12si over the 10si, but we're talking 40 year old cars that don't really NEED anything better than what they came with! The 12si cools better and is more efficient - but will the owner notice? Heck no, you won't see a thing unless the unit you took off was FAULTY or WORN OUT anyway - and if that's the case, I can make it like NEW.

And there is the truth of the matter - it's a choice, not a need.
It's not really an upgrade - not if the swap is simply to not have to deal with parts stores that don't know what they are doing, or perhaps because parts are harder to find. 
I fail to see any GOOD or logical reason the swap is an "upgrade". How is it better other than being easier for the owner to deal with? 
I see but one reason - maybe two - the GM alternators are all over the place, a dime a dozen and even WALMART stocks parts like regulators, etc.
And because so few understand electrical circuits they get confused with 3 or 4 wires compared to 1 or 2.
The 12si is an "upgrade" in a sense that it cools better....... and you can get higher output, but the need for the higher output is due to marketing, cool factor, more is better in the mind, etc.
But a 40 year old car that doesn't have a mega-watt stereo, high-tech EFI and high-wattage off-road lights doesn't "need" an alternator upgrade. They simply need a good working alternator. 
Almost every swap is a "want" or desire and at least partially based on bad or misinformation - and marketing tactics of Jegs, Summit, etc. They do a great job of selling what people don't need - by generating a want. There's the cool factor - "it's cool to have more" even if that 70 amp alternator never kicks out over 40, it's bragging rights in some cases.
And it's lack of understanding - wiring, etc. I'm trained and experienced in it and still have to battle "I once made this change and it worked, therefore I know about these things". Sorry, no. 

If you "don't want to mess with" the original and have been talked into "something different is better" then it won't really matter if it's a 10si or something later because any alternator of similar output would work - keeping in mind the Motorola has lower spinning mass, is physically smaller and has very good output at idle (which means you have to go to very late technology to beat it)
All that matters is that it keep up during in-town driving, or at idle, etc. - and unless you have modified
the car the stock system IF PROPERLY REPAIRED and all of the wiring is in good shape will do just fine. And I don't mean "remanufactured" units - those may be ok - or maybe not, the luck of the draw in too many cases. You'd be amazed at the remans I have on my shelves - as cores - and all that I find wrong with them.

In any case, most alternator swaps aren't truly UPGRADES. Many are done for the wrong reasons - based on marketing, bad or misinformation, etc. 
Like so many things - they only put out as much as is needed by the system. 
A 40 year old car doesn't need the latest aerospace design charging system. If it keeps up at idle, in town and can handle the load, that's enough and plenty. 
Most STOCK systems will do more than fine assuming they are properly dealt with and repaired. 
I have 45 years in auto electric systems........ including Porsche, VW, AMC, Triumph, and every domestic company in business since the 1950s save for DeLorean, perhaps, LOL
Back to Top
304-dude View Drop Down
AMC Addicted
AMC Addicted
Avatar

Joined: Sep/29/2008
Location: Central Illinoi
Status: Offline
Points: 9081
Post Options Post Options   Thanks (0) Thanks(0)   Quote 304-dude Quote  Post ReplyReply Direct Link To This Post Posted: Oct/04/2017 at 10:49am
Vinny and billd are correct in their points. What is overlooked easily is battery condition. As batteries age their internal resistance becomes a block to lower volage charge. Since charging is current related, the low idle voltage of a 10SI below 750 RPM idle, or even a wee higher.

I use to have an output curve for engine RPM on some alternators. There are a ton of varying pulley sizes to either boost low engine speed charge for tow, or police package. Basically over driving. For smaller engines an under drive for fuel economy and smoother idle under load.

What vinny may be experiencing is the load of the battery is become too great to charge with his 10SI.

Newer alternators do have higher low speed idle, and better circuitry, though one must know which application the alternator came from, as you may obtain an overdrive pulley unexpectedly.

Not all batteries will last 20 years let alone 15, especially in snow and heat belts. Some just fail when you need them most, or slowly die with age. Just the slow ones need to be carefully noticed, than ignored. Once a good load effects an old battery, the charge becomes less and less in capacity.

I think the best option is to find the alternator to fit the needs of your electrical system, and hopefully high efficency.

Billd is right in not going bonkers with over kill. A good battery will do more for you in the long run. We went with an AGM battery, as weather has been harsh on our car batteries.

For my build, I am actually running an under drive on a high output alternator. Mainly because of duty cycle with current. You get longer life, better results running around 50% of the rated output. Most only achieve 75% of rated output. This is where output to RPM curve chart comes in handy.

Ps... billd must have been typing as I started. Very odd that I am on the same track with him as of late.
71 Javelin SST body
390 69 crank, 70 block & heads
NASCAR SB2 rods & pistons
78 Jeep TH400 w/ 2.76 Low
50/50 Ford-AMC Suspension
79 F150 rear & 8.8 axles
Ford Racing 3.25 gears & 9" /w Detroit locker
Back to Top
dkrtgood View Drop Down
AMC Addicted
AMC Addicted
Avatar

Joined: Jun/27/2011
Location: St Pete, FL
Status: Offline
Points: 1370
Post Options Post Options   Thanks (0) Thanks(0)   Quote dkrtgood Quote  Post ReplyReply Direct Link To This Post Posted: Oct/04/2017 at 10:55am
Bottom line, going to a 10 or 12SI alternator make 100% sense just for the fact that you can buy one at any parts store...unless you have a show car that gets trailered around and see's 50 miles per year then stick with a Motorola but if you drive your car daily I find peace of mind knowing if (And when) my alternator fails I can buy one anywhere..add the benefit of better amperage and it's a win win. I myself created a complete 100% new wire harness from tail lights to headlights including new style fuse panel and accounted to the better amperage the GM alternator provides to make sure I did not overload anything. 

My stick car idles at just over 500 rpm and have a solid 14 volts at idle....it's a 10SI

Dave Goodwin
President of Tampa Bay AMC

70 Mark Donohue BBO 390 5-speed
77 Matador Coupe AKA "The Beave"
70 Javelin 360 / Auto - BBG


Back to Top
 Post Reply Post Reply Page  <12345 6>
  Share Topic   

Forum Jump Forum Permissions View Drop Down

Forum Software by Web Wiz Forums® version 12.03
Copyright ©2001-2019 Web Wiz Ltd.

This page was generated in 0.156 seconds.
All content of this site Copyright © 2018 TheAMCForum unless otherwise noted, all rights reserved.
PROBLEMS LOGGING IN or REGISTERING:
If you have problems logging in or registering, then please contact a Moderator or