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Jumping a Positve Grounded Battery

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J

J Eade

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Perhaps a silly question, but how does one jump start a dead battery which is positively grounded with a battery/car that is negatively grounded?
 
I've always gone positive to positive terminal and negative to negative. I've never had an issue on any British or old American car I've owned.
 
Sam B. has it right. If you mind the polarities between the two batteries and connect as he states, there's no problem. You should not allow any metal parts such as bumpers on the two cars to touch. If you do cross connect the batteries, you will burn out the diodes in the alternator of the negative ground car - I have had enough experience at this to tell you for certain that is what will happen! AL Bradley
 
And make the last connection the ground connection on the car with the dead battery -- making that connection to a good ground away from the battery (e.g. a forward head bolt). Also make that the first connection undone. Only the last connection can spark... doing it that way assures any sparks are not near either battery.
 
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