1) It is my understanding that you can even jump different-polarity cars as
long as you put the negative cable on the battery terminal itself and not
the body of the vehicle. I confess to never having tried it myself.
2) Not to start a thread on the "Right Way to jump" (probably too late) but
I have always jumped vehicles connecting neg-to-neg, then pos-to-pos. I
have seen some official instructions on a cable set indicating the opposite
(that is, pos first), but never understood why. By connecting the negs up
first you ensure there's a return path for when you go to do the pos's, or
so I've thought. I've jumped a lot of cars this way (living in toasty New
England) and have never had a problem, but if someone knows why pos should
connect first, I'd like to hear it.
3) I always have the jumper running, and the jumpee of course is off, and I
hook them up. Depending on how drained the jumpee is, they may need to be
hooked up only for 5 seconds to get it started, or twenty minutes if it's
really shot. Keep in mind to drive the jumpee for a while after (I usually
give it a good 30 to 45 minutes) to give the alternator a chance to
recharge the battery.
4) Also, it never hurts to own a battery charger. I have one I paid maybe
$35 for - don't really recall - that I had been using for my lawn mower,
but had chance to use it on my Toyota the other day. I had left the dome
light on or something and had not gone near it for nearly a week (driving
my B instead) and it was well and dead by the time I went to turn it on.
Unfortunately, it is an automatic, and was in my garage. Not a problem - I
figured I'd roll it out and jump the battery with another vehicle as donor.
Alas, it has a safety device that precludes the transmission from being
shifted when the engine isn't running, so I had no way to shift it from
Park to Neutral to allow it to be pushed out of the garage (of course, it
was in nose first). I ended up having to use the battery charger. The
only other alternative would have been to borrow some Really Long jumper
cables from my local mechanic, or to make a new entrance to the garage.
At 12:40 PM 12/13/99 -0500, James H. Nazarian wrote:
>Your 1976 MGB is wired "negative to ground"; so is virtually every car
>at least 1970. If you are going to jump start from another vehicle,
>both cars have their negative lead (should be black) grounded to the frame or
>body close to the battery. If you confirm that, be certain the two cars
>touching metal to each other, then clamp one end of your jumper cable set
>piece of wood, again confirm that the two clamps do not touch each other.
>the other end of the jumper cable set to the boosting battery, clamping
>red lead to the positive battery terminal, then clamp the black lead to the
>negative terminal or a good ground point.
>Bring the opposite end of the cable set (still clamped to the wood) to
>battery; clamping first the red lead to the positive battery terminal,
>the black lead to the negative terminal or a good ground point such as the
>that holds the battery. Start the boosting car; let it run. If you are
>light gauge jumper cable set, leave the two connected this way for 5-10
>Now start the "B" as you normally would. Leave the connections on until
>warms up. When fairly certain that the MG will stay running, turn off the
>car and begin to disconnect the clamps in the opposite order as they were
>connected: MG Black, clamp to wood, MG Red, clamp to wood, other car
>If you are going to jump start from your battery charger, the process is
>Connect the black and red leads from the charger to the MG battery
>positive terminals respectively. Turn on the battery charger for a 5 minute
>charge. at the end of that time, switch over to the start position and
>MG as usual. As soon as the MG starts, switch off the charger, and remove
>the car is running smoothly.
>BTW if you are doing this in a garage or unclosed space, watch the
>with two cars running, you will suffocate before they do, and that's no
>Scott Regel wrote:
>> Can you jump start the "B" without frying anything? I have a battery
>> that can jump start it, but was wondering if I would be opening a can of
>> worms. I've got to get a new battery, but don't have the funds until
>> of the month and the weather has just been to nice! TIA, also thank you
>> for all your great help and input on this list. Talk about a support