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#98646 12/27/2006 7:25 AM | Joined: Nov 2006 Posts: 96 Wrench Fetcher | | Wrench Fetcher Joined: Nov 2006 Posts: 96 | I'm installing a 2 wire alternator.
It's been a while since I've wired one and I can't remember exactly how to wire it.
I'm not using a ignition switch with an accessory, just a simple on off key switch, plus an amp gauge.
It's a '42 GMC, Stock 6 cyl. converting to 12v. Neg ground.
All the wiring is trashed I've wrecked it out and am rewiring from scratch. | | |
#98647 12/27/2006 6:29 PM | Joined: Jul 2004 Posts: 5,708 'Bolter | | 'Bolter Joined: Jul 2004 Posts: 5,708 | mmcdaniel69,
I have enclosed a link to a previous thread on this subject because it has a clear diagram of the wiring.
Most folks refer to your setup as a three wire alternator as opposed to the single wire unit.
There are actually two, three wire alternators. One still needs an external regulator while the other has a internal regulator. The more modern internal style are referred to as a SI alternator...a rough translation would be 'system internal' meaning internal regulator.
If you look at the diagram in the link, you will see that basically, your main "BATT" output needs to get into the system, or to the battery somehow. In your case, this might be through the ammeter.
The wire on the DA plug marked #2 needs to be attached somewhere in the system to monitor voltage and regulate the on/off of the alternator.
Wire #1 need to be connected to a switched source of voltage that is ON when the rig is running. This voltage excites the alternator and turns it on so it will charge.
Look at the diagram, come back if you have questions. Good luck.
Make sure your alternator is not a external style. The DA plug configuration is the key to the type.
http://www.stovebolt.com/bboard/cgi-bin//ultimatebb.cgi?ubb=get_topic;f=3;t=002229#000009
Stuart | | |
#98648 12/27/2006 7:20 PM | Joined: Nov 2006 Posts: 96 Wrench Fetcher | | Wrench Fetcher Joined: Nov 2006 Posts: 96 | Thanks, automarc.
Great diagram.
I think I'll change out my ignition switch as it only has two post(line and load) so I'll have enough posts to connect everything.I'll need to anyway so I can run accessories, stereo etc..
Can I pick up a DA plug with a built in resistor at an auto parts store, or if not, where's the best place to find a resistor? | | |
#98649 12/27/2006 7:43 PM | Joined: Jul 2004 Posts: 5,708 'Bolter | | 'Bolter Joined: Jul 2004 Posts: 5,708 | mmcdaniel69,
I'm not sure on the plug/resistor. I have heard that the auto parts stores have them. I would bet a farm store that deals in tractors etc might have them too.
Some folks have even made their own with a small diode from Radio Shack, and I think I have read that on some occasions, the rig didn't experience 'run-on' even without the load in the line.
If you do a search in this forum using phrases like 'diode' or 'engine won't shutoff' you might find some real life examples. Good luck.
Stuart | | |
#98650 12/27/2006 8:28 PM | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | dang!! thanks Stoo! I've had a buddys truck here for awhile waiting for me to detail out some bugs from the "pros" who did the mechanical and electrical [and body/glass!] - one problem is the thing [350/350] runs on unless a wire's pulled off the ign sw - something's been niggling at the back of my pea brain saying it ain't a bad switch like buddy thinks, but I haven't had time to think about it .... this twigs me that the mechanic picked an alternator that didn't match the generic "painless" harness! easy fix on that problem  Bill | | |
#98651 12/28/2006 8:23 PM | Joined: Nov 2006 Posts: 96 Wrench Fetcher | | Wrench Fetcher Joined: Nov 2006 Posts: 96 | | | |
#98652 12/31/2006 8:27 AM | Joined: Jul 2005 Posts: 2,031 Shop Shark | | Shop Shark Joined: Jul 2005 Posts: 2,031 | Mike, you may find what you're looking for here... simple key switches http://www.colehersee.com/catalog_top/index.htm go to switches colehersee .... is CH on keys Switches Electronic Dimmer & Rheostat Headlamp Dimmer Ignition Momentary Door/Momentary Neutral Safety, Back-up Lamp & Alarm Oil, Air, Vacuum & Fuel Pump Push-Pull ROCKER Head Lamp Rotary & Fuel Tank Senders & Temperature Solenoids Stoplamp TOGGLE Windshield Wiper
Jim & Caroline
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