Starter Problem

["petrellaj" <petrellaj@domain.elided>]

I'm having an occasional problem starting my 85 Graduate. Every three 
or four days, when I turn the ignition, nothing happens. No click, no
grind, nothing. As soon as I hook jumper cables up it fires right up.
I have a new battery, connections are tight, grounds are good. Alternator
seem to be charging. What might it be? Thanks for the help.

John Petrella
Atlanta, GA
73 BMW 2002 (restoration)
85 Spider
94 Infinity J30 (wife's)

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