No Crank, No Start

[DCMotoring]

My '78 530i gets full power (lights, interior accessories) when key is in ON position but absolutely nothing happens with starter when I attempt to start it.

Battery voltage at starter is about 12.5v and there is about 7.5v coming from the ignition switch when in the ON position. I connected a jumper cable from the - terminal of the battery to the engine block in case there was a ground issue and still nothing. So I don't think it is a ground issue.

Is it safe to say it's the starter or should I not rule out the battery or ignition switch yet? I plan on cleaning all the connections and charging/testing the battery, but wanted to see if anyone has any other suggestions.

Thanks!

[Mike W.]

7.5V, somethings wrong. Either low battery or measurement or something. I'd just out a hot wire to the starter start lead before I'd do a starter just to make sure. Starters usually die slowly not all at once. Try giving the starter a bang too, I've seen that work on more than one make of car.