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ignition coils |
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wjkrostek
Silver Level Joined: 18 Dec 2010 Location: Wasilla alaska Points: 131 |
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Posted: 18 Aug 2017 at 10:26pm |
does anyone know if there is an ignition coil that runs on 12 volts all the time no just for starting. How do the ones with internal resistors work? Thanks
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Burgie
Orange Level Joined: 13 Sep 2009 Location: Scottsburg, IN Points: 1192 |
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I quit using the external resistors and use the 12 volt coil with the built in resistor.The external is just something else to go bad.
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"Burgie"
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DougS
Orange Level Joined: 03 Nov 2011 Location: Iowa Points: 2490 |
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When carmakers changed over to 12 volts, they continued to use 6 volt coils. They would use a ballast resistor in series with the coil so as to limit the current, lest the coil get too hot or the points burn. It wasn't unusual to bypass the resistor while cranking the engine, which would give a hotter cranking spark. Some used ballast resistors and some used resistance wire. My old '67 Cougar used resistance wire. Eventually they started building the resistor into the coil. The resistor is internal to the coil and you can't bypass it. Some coils were labeled as "12 volts when used with resistor." Well duh, I suspect this was more a marketing way of selling a 6 volt coil. In theory you can double the primary turns in a coil and get the same input results as using a resistor, but that will halve the secondary voltage. You can double both turns, but in theory your condenser won't match. I suspect this is what they've done with these "high energy" coils, but you're more likely to see those matched with an electronic ignition system. The bottom line: You don't want to use a 6 volt coil in a 12 volt system without using a resistor. You'll start burning out points and overheating the coil. At the opposite end you don't want to use a true 12 volt coil in a 6 volt system because you won't be generating a very hot spark. |
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CTuckerNWIL
Orange Level Joined: 11 Sep 2009 Location: NW Illinois Points: 22818 |
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Any coil made for a 4 cylinder engine with 12 volt system will work. I had one listed for a Volkswagen on the CA when I put the alternator on it years ago. Should measure 3 ohms on primary winding.
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http://www.ae-ta.com
Lena 1935 WC12xxx, Willie 1951 CA6xx Dad bought new, 1954WD45 PS, 1960 D17 NF |
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