I've got a 1987 Mercruiser 3.0L with an AlphaOne. My problem is when I turn the key to start the engine, my starter wont disengage. If I turn the key OFF, the engine and starter won't quit. I've found the only way to kill the engine is to pull the positive battery cable. This just started happening. I've had lots of hours on the boat since the engine was rebuilt.
I first suspected it was the ignition switch, so I put a new one in; same issue. I took the starter off and had it tested at a marina. They told me the starter was fine and it was likely the slave solenoid. I replaced the solenoid and put the starter back in, but I still have the same problem! I had to get the boat back to the launch so I had to get it running. In order to get the motor running without the starter engaged, I turned the key to start it. Once the engine and starter were on, I pulled the positive cable. After a second or two the engine started to die down I put the cable back on and I had a running engine without the starter. I was able to get the boat back to the ramp.
I think the Marina is wrong and my starter solenoid (mounted on starter) is shot. I ruled out the ignition switch and the slave solenoid.
Thoughts?
**update: Solenoid on starter was shot. Replaced starter and boat starts normally. Trust your instinct, not what the marina says..**
I first suspected it was the ignition switch, so I put a new one in; same issue. I took the starter off and had it tested at a marina. They told me the starter was fine and it was likely the slave solenoid. I replaced the solenoid and put the starter back in, but I still have the same problem! I had to get the boat back to the launch so I had to get it running. In order to get the motor running without the starter engaged, I turned the key to start it. Once the engine and starter were on, I pulled the positive cable. After a second or two the engine started to die down I put the cable back on and I had a running engine without the starter. I was able to get the boat back to the ramp.
I think the Marina is wrong and my starter solenoid (mounted on starter) is shot. I ruled out the ignition switch and the slave solenoid.
Thoughts?
**update: Solenoid on starter was shot. Replaced starter and boat starts normally. Trust your instinct, not what the marina says..**
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