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| | | | Joined: Feb 2008 Posts: 217 Shop Shark | | Shop Shark Joined: Feb 2008 Posts: 217 | I've got the modern EZ wire kit and a modern 3 wire alt. I'm wondering:
1. do I need to install a diode from the number 1 terminal on the back of the alt?
2. If I need to install a diode where do I connect this wire from the number one terminal on the alt to? Does it go to the ignition switch? If so which contact, start or batt or acc or ign?
Or does it go to the starter?
Rick....... | | | | | Joined: Feb 2004 Posts: 29,886 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,886 | The diode is usually necessary to prevent current feedback to the ignition system if you're not using an idiot light. The engine will run on if enough current feeds back from the alternator to keep the coil firing. The #2 wire can be connected directly to the big battery terminal at the back of the alternator housing, but the #1 wire needs to have switched voltage either from the coil input or the ignition switch. A 100 ohm 10 watt resistor works about as well as a diode.
Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!
| | | | | Joined: Feb 2008 Posts: 217 Shop Shark | | Shop Shark Joined: Feb 2008 Posts: 217 | Jerry,
Thanks for the reply. That's sounds exactly what I have now. The number 1 wire goes through a diode then splits with one wire going to the pos side of the coil and the second wire goes to the switched side of the ignition switch. If this sounds ok I will go back the same way with the new wires.
Thanks. | | | | | Joined: Feb 2004 Posts: 29,886 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,886 | That will work, but GM chose to make the #2 terminal hot all the time in the OEM wiring harness- - - -no switching whatsoever for some reason. Going to both ign. switch and coil with the same circuit, then to the #1 terminal makes no sense at all. Use one or the other, not both.
Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!
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