100293R Wont shut off with key

mike7908

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Mar 13, 2010
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I am working on an old 72 100hs evinrude I have recently replaced the clipper circuit, rectifier, coil, stator, and power pack, keep in mind before i replaced all those items it shut off with the key, however the stator and rectifier only had two yellow wires instead of one yellow and one yellow with grey stripe. Does it matter how those wires are hooked up and would that be the problem. Any advice would be greatrly appreciated. Also can anyone tell me where i can get a good (prefferably colored) wiring diagram for this motor, I have the book but is kind of hard to follow the wires.

Thanks,
Michael
 

Joe Reeves

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13,262
Re: 100293R Wont shut off with key

There should be a diode in the control box leading from the "I" terminal of the ignition switch to the purple (+) wire of the shift switch. This allows voltage to flow from the ignition switch to the shift switch BUT blocks voltage that flows from the charging circuit to the shift switch and then to that "I" terminal of the ignition switch.

Now, if that diode is shorted or does not exist (somebody simply replaced it with a piece of wire?)..... that allows charging voltage to flow to the "I" terminal of the ignition switch which makes it impossible to shut the ignition off.
 

F_R

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Re: 100293R Wont shut off with key

There should be a diode in the control box leading from the "I" terminal of the ignition switch to the purple (+) wire of the shift switch. This allows voltage to flow from the ignition switch to the shift switch BUT blocks voltage that flows from the charging circuit to the shift switch and then to that "I" terminal of the ignition switch.

Now, if that diode is shorted or does not exist (somebody simply replaced it with a piece of wire?)..... that allows charging voltage to flow to the "I" terminal of the ignition switch which makes it impossible to shut the ignition off.

I agree with Joe. Further explanation: If the rectifier was blown, the alternator wasn't working. It is the alternator that feeds back through the ignition if the blocking diode is bad or missing. So, you fixed the alternator and now it is feeding the igniton through the blown or missing blocking diode. "Blocking" because that is what it does--blocks the alternator from feeding the ignition.

Also, confirming the yellow and yellow/gray hookup matters not.
 

mike7908

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Re: 100293R Wont shut off with key

Thanks for the info, I will dig into trhe switch and see if there is a diode. If it is not there is that something i can purchase at radio shack and what is the number?

Thanks,
Michael
 

Joe Reeves

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Re: 100293R Wont shut off with key

Yes, Radio Shack is fine..... just a simple small two wire diode capable of handling 12 volts.
 

mike7908

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Re: 100293R Wont shut off with key

Well thanks for the advice. Sure enough they had the purple wires tied together so i took them apart and walla it shuts off so i will be hitting radio shack tomorow. Once again thanks

Michael
 

F_R

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Re: 100293R Wont shut off with key

Well thanks for the advice. Sure enough they had the purple wires tied together so i took them apart and walla it shuts off so i will be hitting radio shack tomorow. Once again thanks

Michael

Not so fast there. "12 volts" is a nominal expression. In reality for a safety margin it should be about 50 volts, especially considering it is an inductive load. More is better than less. And it needs to carry a minimum of about 5 amps. Again, allow a safety factor. Radio Shack will probably call it a "power rectifier" or something of that nature.
 
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