If a jump starts a car, and the negative cable from the 2nd car, battery
is attached to the frame of the 1st car, not the battery, as it should
be, it is not necessarily the battery of the 1st car that is bad, as it
could be a bad ground wire or ground wire connection from the 1st car's
battery.

But it is a good indication that it is not the starter.

BTDT, long story about a shop selling my then "not quite ex wife" a
bunch of stuff while I was out of town, it failing again and then me
trouble shooting it for them and finding the bad ground wire while in
their shop.     I told her it wasn't the starter because it would start
when jumped, she told them, but they didn't listen, for some reason,
like that the info was coming from a woman, and/or that the guy hearing
it wasn't sharp enough to understand and then check, or was it that
simply replacing a bad ground wire doesn't make much money?).  (That is
the short version.)

--
Sam Walters
Baltimore, MD

89 Syncro GL
85 Westy Weekender
84 Vanagon, original owner, soon to be retired, just too many problems

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