Battery Question - Bayliner 175 3.0 MerCruiser

[stonyloam]

I kinda screwed up my last post, so I’ll try again. With your voltmeter check to see if you have 12v on the large red/purple wire terminal. If you do, then you want to bypass the ignition switch by jumpering from that r/p terminal to the small r/y terminal. If the solenoid closes and the starter runs, then you have a ignition switch or wiring problem. If it does not run then the solenoid is bad. A second check is, put the voltmeter on dc volts red probe on the small r/y terminal, black probe on ground. Have someone hit the key start. If you read 12v on the meter and the solenoid DOES NOT click and the starter run, then you have a bad solenoid. No 12v, then bad switch or wiring.

 

[MikesBayliner]

Thanks for the feedback. I won't be back at the boat for another week or so and will update the post when I've tried the above suggestions.

 

[isaksp00]

I just dissected what was a bad salve starter solenoid for a Mercruiser 4.3, see this thread. I don't know what causes this kind of carbon buildup, but if you got a bad solenoid or one prone to failure, the inside might look like this. Maybe buy one from Mercruiser and try it?