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Jump Starting Positive Earth cars.

John Morralee

Senior Member
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I have been reluctant to jump start my '63 BJ7 due to being unsure about the positive grounding factor. I noted recent posts that there was no real problem it was just pos.to pos. neg. to neg.. I needede to jump start ,did as the posts said --- and melted the pos. terminal on the BJ7!! No other damage found sofar. What did I do wrong and what is plan B??
 
Holy Smokes.

I take it the 7 is totally dead?
I would suspect a shorted battery or some other serious load, like maybe a jammed solenoid and shorted starter.

IF you did positive to positive, NOT red to red (as who knows what color cables have been put on either car in the past), jumping a positively earthed vehicle is NO problem.

I've done Flathead Fords (every one six volt positively earthed) for 45 years or more, plus Limey Limos.

Double check the marks on the battery case itself.

Just check.

Dave
 
John Morralee said:
I have been reluctant to jump start my '63 BJ7 due to being unsure about the positive grounding factor. I noted recent posts that there was no real problem it was just pos.to pos. neg. to neg.. I needede to jump start ,did as the posts said --- and melted the pos. terminal on the BJ7!! No other damage found sofar. What did I do wrong and what is plan B??

Well John, Plan "B" might be to completely remove the Positive cable from the BJ7's battery and briefly retry the connections again.IF you get excessive heating at the"pos.terminal" and or sparks the battery is shorted . If you do not, then there is potentially a short on the car's [- VE] Voltage bus that must be corrected
FWIW--Keoke
 
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