sidevalvepete Posted July 20, 2020 Report Posted July 20, 2020 https://ebay.us/WMSJIU Have been looking for a replacement coil for my 38 D9 Dodge and saw this in the above link. My car is running original 6 volt positive earth system which I understood to be what all the Chrysler Corporation vehicles were running back then. So this coil seems odd to me, being negative earth. Anyone with way more knowledge than me that can explain this? Am curious and still have a lot to learn. Quote
Sniper Posted July 20, 2020 Report Posted July 20, 2020 Coils don't care what the ground is, other than you wire it proper in some cases. My 51 had it's coil wired backwards and you couldn't tell, but I've worked on other brands that wouldn't run if the coil was wired backwards. Looking at the Ebay offering, I suspect the seller confused the "NEGATIVE" label that shows which post is negative, for it being a negative ground coil. As a rule, I don't use Ebay as a source of technical information, most of them have zero clue. 1 Quote
Jack L Posted July 20, 2020 Report Posted July 20, 2020 Manufactures wanted the coil polarity such that the plug would fire from the center electrode to the ground. Later systems , HE, waste spark, etc., had enough "snap" that firing polarity was not a concern. As Sniper stated, there are times when you wouldn't notice it if wire incorrectly. Quote
greg g Posted July 20, 2020 Report Posted July 20, 2020 Unless you are going for show points or a total restoration, it isn't necessary to spend that much to get your car on the road. Any coil that is not internally resisted will work just fine. 12volt coils in many modern systems are wired through a resistor to drop their working voltage to 7 volts or so. So if you wire it up without the resistor to your six volt system it will be happy. As for the terminals for positive ground system, neg to ignition, pos to distributor. 1 Quote
50mech Posted July 20, 2020 Report Posted July 20, 2020 2 hours ago, Sniper said: Looking at the Ebay offering, I suspect the seller confused the "NEGATIVE" label that shows which post is negative, for it being a negative ground coil. As a rule, I don't use Ebay as a source of technical information, most of them have zero clue. +1 every vehicle it applies to uses a positive ground. The years specifically correlate to the dates for positive ground in the listed brands. Quote
sidevalvepete Posted July 20, 2020 Author Report Posted July 20, 2020 Thanks for the replies. They all help. Cost is always a factor but the biggest bargain is useless if it is the wrong application. ? Quote
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.