My Alt needs more excitement!!!
Thread Starter
Safety Car
Joined: Mar 2007
Posts: 3,652
Likes: 49
From: Bridgewater nj
My Alt needs more excitement!!!
Hey guys, I've been doing research on these new self exciting alternators and can't seem to find a way to get my alt to turn on without Revving the engine. I find it a problem in the cold weather, I'll go out to warm the car up but I don't want to rev a cold engine and it will take a few tries before it turns on. I have all 3 Oem wires connected and it charges great when it turns on but I'm wondering if there's a jumper wire or capacitor I can install to light it off or do I have a bad alternator and need to return it. Thanks for reading.
Race Director
Joined: May 2006
Posts: 18,742
Likes: 2,583
I have seen one wire alternators but what is a 3 wire "self exciting"? Who makes it? Did you use a hand held voltmeter to check what the reading is when you turn it on? What rpm is your fast idle set for?
Last edited by MelWff; Jan 13, 2016 at 01:55 PM.
Burning Brakes
Joined: Apr 2008
Posts: 1,222
Likes: 93
From: shelbyville West Michigan
do more research on them. that is how they work, by leaking current. very inefficient and not recommended...why do you think the OEM's don't use them?
btw, there is a way you can put in a momentary switch to get it to start charging without revving it, it's what we use in tractor conversions, but for all the work, why not just put the proper alternator back on?
btw, there is a way you can put in a momentary switch to get it to start charging without revving it, it's what we use in tractor conversions, but for all the work, why not just put the proper alternator back on?
Melting Slicks
Joined: Apr 2009
Posts: 2,632
Likes: 112
From: Great Plains Iowa
Hey guys, I've been doing research on these new self exciting alternators and can't seem to find a way to get my alt to turn on without Revving the engine. I find it a problem in the cold weather, I'll go out to warm the car up but I don't want to rev a cold engine and it will take a few tries before it turns on. I have all 3 Oem wires connected and it charges great when it turns on but I'm wondering if there's a jumper wire or capacitor I can install to light it off or do I have a bad alternator and need to return it. Thanks for reading.
Its very common for the single-strand wire in the side plugin to break inside the insulation right next to the terminal and when it does break it often takes a revving engine to vibrate enough for the wire to make contact. Those side plugins are available from any auto parts store for about $5.
Burning Brakes
Joined: Apr 2008
Posts: 1,222
Likes: 93
From: shelbyville West Michigan
no that's not why, the reason is because the iron core is magnetized slightly and revving it fast enough through the windings produces a very weak current which is used to excite the alternator when the RPM's are high enough. that is how they are designed, otherwise they would be fielding out when you try to start the engine when it turns over...bad...you also give up the remote voltage sensing of a regular alternator, which isn't a big deal on a tractor or boat, but on an old vette with all the wiring connections and aged terminals? you're just asking for trouble...
Thread Starter
Safety Car
Joined: Mar 2007
Posts: 3,652
Likes: 49
From: Bridgewater nj
Thanks every body. I checked the 2 prong plug and it's been replace. Connections are good. Voltage gauge works perfect. I purchased this alt from Advanced auto. I'm pretty sure most of these alternators are a one wire setup but they leave the side plug for the gauge, I've also seen them advertised as either/or.
I am interested in that switch that excites the alt. I too have some old tractors and will be looking at coversions when their charging system goes to the happy hunting ground. I was thinking of using a capacitor from my old Harley. The old bikes had a huge one to keep the headlight steady at idle. That should excite an alt pretty good!
I just have no idea how to wire it in? I can build any engine, manual trans and most things mechanical but electricity befuddles me at times. I'm just not sure what exactly is going on inside that alt to start hooking wires to it. That and the $90 I spent on it
I am interested in that switch that excites the alt. I too have some old tractors and will be looking at coversions when their charging system goes to the happy hunting ground. I was thinking of using a capacitor from my old Harley. The old bikes had a huge one to keep the headlight steady at idle. That should excite an alt pretty good!
I just have no idea how to wire it in? I can build any engine, manual trans and most things mechanical but electricity befuddles me at times. I'm just not sure what exactly is going on inside that alt to start hooking wires to it. That and the $90 I spent on it
Last edited by hugie82; Jan 14, 2016 at 08:24 PM.
Burning Brakes
Joined: Apr 2008
Posts: 1,222
Likes: 93
From: shelbyville West Michigan
First of all, you need to see if you truly have a "1-wire" alternator, and not just some hybrid. if you have the 2 spade plug wires hooked up, what are they hooked to? what are they doing? that plug is normally blocked off on a 1-wire alternator. If the 'F' is hooked up, and getting power with key on, but not running, it will start the alt. charging immediately when running. you say this is not happening. either it is not hooked up correctly, or it is going nowhere in the alternator as it was replaced with a 1-wire regulator. a true 1-wire alternator is set to charge at a lower RPM than a pseudo-1-wire...
not having power on the 'F' or #1 terminal will make you rev the engine to get it charging (voltage leakage). if your alt light in the dash is burned out, it won't charge until you rev it as well.
before I go into any more detail you really need to post exactly what you have, where you got it, model#, pics, etc...
not having power on the 'F' or #1 terminal will make you rev the engine to get it charging (voltage leakage). if your alt light in the dash is burned out, it won't charge until you rev it as well.
before I go into any more detail you really need to post exactly what you have, where you got it, model#, pics, etc...
Racer
Joined: Jan 2016
Posts: 290
Likes: 78
http://www.madelectrical.com/index.shtml
Read the tech section on 10Si/ 12Si AND 1 wire alternators. Explains it all
Read the tech section on 10Si/ 12Si AND 1 wire alternators. Explains it all
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Burning Brakes
Joined: Apr 2008
Posts: 1,222
Likes: 93
From: shelbyville West Michigan
http://www.madelectrical.com/index.shtml
Read the tech section on 10Si/ 12Si AND 1 wire alternators. Explains it all
Read the tech section on 10Si/ 12Si AND 1 wire alternators. Explains it all
fyi from his link go to "electrical tech' at the top and scroll down...
Thread Starter
Safety Car
Joined: Mar 2007
Posts: 3,652
Likes: 49
From: Bridgewater nj
http://www.quietcanyon.com/images/rrdelwiring.jpg
Talking to the guys at advanced auto. I wouldn't call them gurus or even weekend wrenches but they made a few calls and said the alternator can be used as a one wire or a 3 wire. I found this on a few sites. Taking the hot key wire and running it to the hot side will make it turn on but why doesn't it work that way thru the plug? Maybe I'll make up a jumper wire and see what happens. I'm pretty sure I won't ruin anything by doing this. What say you?
Talking to the guys at advanced auto. I wouldn't call them gurus or even weekend wrenches but they made a few calls and said the alternator can be used as a one wire or a 3 wire. I found this on a few sites. Taking the hot key wire and running it to the hot side will make it turn on but why doesn't it work that way thru the plug? Maybe I'll make up a jumper wire and see what happens. I'm pretty sure I won't ruin anything by doing this. What say you?
Thread Starter
Safety Car
Joined: Mar 2007
Posts: 3,652
Likes: 49
From: Bridgewater nj
http://www.madelectrical.com/index.shtml
Read the tech section on 10Si/ 12Si AND 1 wire alternators. Explains it all
Read the tech section on 10Si/ 12Si AND 1 wire alternators. Explains it all
Le Mans Master
Joined: Apr 2015
Posts: 9,433
Likes: 124
Thanks every body. I checked the 2 prong plug and it's been replace. Connections are good. Voltage gauge works perfect. I purchased this alt from Advanced auto. I'm pretty sure most of these alternators are a one wire setup but they leave the side plug for the gauge, I've also seen them advertised as either/or.
I am interested in that switch that excites the alt. I too have some old tractors and will be looking at coversions when their charging system goes to the happy hunting ground. I was thinking of using a capacitor from my old Harley. The old bikes had a huge one to keep the headlight steady at idle. That should excite an alt pretty good!
I just have no idea how to wire it in? I can build any engine, manual trans and most things mechanical but electricity befuddles me at times. I'm just not sure what exactly is going on inside that alt to start hooking wires to it. That and the $90 I spent on it
I am interested in that switch that excites the alt. I too have some old tractors and will be looking at coversions when their charging system goes to the happy hunting ground. I was thinking of using a capacitor from my old Harley. The old bikes had a huge one to keep the headlight steady at idle. That should excite an alt pretty good!
I just have no idea how to wire it in? I can build any engine, manual trans and most things mechanical but electricity befuddles me at times. I'm just not sure what exactly is going on inside that alt to start hooking wires to it. That and the $90 I spent on it
A cheap easy way to have a one wire is to use a GM alt. that is new enough that it does not require an external voltage reg. Like a 1978 or something around that year. Simply jump the Two spade connectors together, and run the big wire from the alt. strait to battery positive. You do have to rev this set up one time on start up to excite the field, and kick it into charge mode.
We used to upgrade old boats with this set up. It would work on anything if you fabricated the brackets to mount it.
Thread Starter
Safety Car
Joined: Mar 2007
Posts: 3,652
Likes: 49
From: Bridgewater nj
I have had this problem and returned the alt. for another one, and solved the problem. It can be the alt.
A cheap easy way to have a one wire is to use a GM alt. that is new enough that it does not require an external voltage reg. Like a 1978 or something around that year. Simply jump the Two spade connectors together, and run the big wire from the alt. strait to battery positive. You do have to rev this set up one time on start up to excite the field, and kick it into charge mode.
We used to upgrade old boats with this set up. It would work on anything if you fabricated the brackets to mount it.
A cheap easy way to have a one wire is to use a GM alt. that is new enough that it does not require an external voltage reg. Like a 1978 or something around that year. Simply jump the Two spade connectors together, and run the big wire from the alt. strait to battery positive. You do have to rev this set up one time on start up to excite the field, and kick it into charge mode.
We used to upgrade old boats with this set up. It would work on anything if you fabricated the brackets to mount it.
Burning Brakes
Joined: Jul 2015
Posts: 823
Likes: 57
From: Austin TX
Isn't that the purpose of the battery and regulator? No modern alternator/regulator/battery system should need such a thing, either to steady the lights or to start the alternator.
Advanced
Joined: Aug 2012
Posts: 55
Likes: 4
The stock GM charging system routing leaves A LOT to be desired. Add modern electrical devices and it gets worse. Voltage drop is the biggest killer. 2nd issue is cheap offshore rebuilt alternators using sub-standard rectifier diodes, stators, regulators, ect. I prefer to upgrade to a late model designed engine harness when doing any kind of serious electrical upgrades.
Advanced
Joined: Aug 2012
Posts: 55
Likes: 4
There are options other than an SI to fit the stock brackets-using a CS130 from an '88 Olds Firenza 2.0 FI bolts directly in place of the SI with the same clocking-just swap the serpentine pulley out for your v-belt style and upgrade the plugin to the CS style. Then solder inline on the "excite" wire a 50 watt 1/2 amp resistor and a diode if you'd like and you'll be setup with 105A from a better designed alternator-at least internally speaking.
Last edited by gmachinz; Jan 19, 2016 at 02:53 PM.