No coil spark on mercruiser 140

[dmounts]

I have a 1986 Alpha One Mercuiser 140(3.0 L) that ran fine last year. This year it wouldn't turnover. We had the starter rebuilt. Now it will turnover but the coil is not producing a spark. We tried, unsuccessfully, jumping/looking for a spark between the secondary coil wire (the one from the coil to the distributor) and several unpainted spots on the block after doing each of the following: 1. replacing the coil with 2 new ones (including 1 from a running car) 2. measuring 11.98V at the + coil terminal, 8v during cranking 3. jumped a wire directly from + battery terminal to + coil terminal 4. disconnected the gray wire at the tach 5. checked the shifter switch by attempting to start (turn the engine over) with the switch in the "in gear" position. No starter activity unless the shifter switch was in the "neutral" gear position. 6. replacing the condensorWhat have I done wrong or what am I missing? The boat is 1.5 hrs from here. So, the more suggestions provided, the more I can try when I work on the boat again.

[snapperbait]

Did you replace the points?? Cap and rotor??

[denniz]

Try unhooking the wire from the shift interrupt switch where the sift cable and transom shift cable connect.

[Mikevn1500]

8v at cranking dont sound rite. Try a dif. Bat. Are all the wires back on the solenoid? I have the same set-up and mine wouldnt start,Turns out my fully charged Bat. Wasn't . Make sure you didn't leave wires off anywhere on the Bat. or solenoid . I'm guessing it's turning over good. Mine spins over fairly fast. Maybe a new solenoid. Clean all wire connections .

[petryshyn]

deanbobThe negative coil terminal is best checked for troubleshooting. You should have battery voltage to the negative terminal when the points are open, and 1 volt or less when they are closed. This will result in a flickering light when cranking if you are using a test light. If voltage stays high when they are closed, you have a problem between the coil negative and ground:>wiring from dist. to coil>points>breaker plate ground strap