Key won't turn off motor?

[mattisonjr]

I have a 1981 Sea Ray 18' runabout with a mercruiser 470. It's been converted to an alternator instead of the stator and I have removed the breaker points in favor of the Pertronic ignition. So after starting this boat for the first time this season and letting warm up, I tried to turn the engine off, of course, using the ignition key. The boat continued to run even after removing the ignition switch from the dash and taking it into the garage. I was able to stall the motor by putting my hand over the carb. What I found was that the coil still has 12 volts continuing to be fed to it. I removed the positive leads from the coil because it was getting very hot.Where could this voltage be coming from?

 

[alldodge]

Try disconnecting your starter relay (small wires only) and see if the power goes away

 

[Bt Doctur]

alt backfeeding from a bad diode

 

[mattisonjr]

Thanks. I'll check it out when it stops raining.

 

[bruceb58]

Disconnect all your alternator wires and try again. Don't just disconnect the output wire or you will blow the alternator. Have to remove the field wire.

Have you ever run your engine and disconnected the battery while running?

 

[stonyloam]

Did you have water going to it all the time it was running?

 

[mattisonjr]

i pulled the starter relay off and found continuity between the battery post terminal of the relay and coil wires of the relay. Guess i need to replace the relay

 

[Bt Doctur]

If it was the starter relay/solenoid wasn`t is making a lot of starter noise/grinding?

 

[mattisonjr]

No. only the post connected to the coil was getting power. There wasn't a complete circuit through the relay,so, it wasn't pulling in the contacts.