Mercruiser 4.5l 200HP 3 years old - engine stopped on its own a few times

[jamesdgreen2016]

https://www.mercurymarine.com/en/ca/engines/inboard-and-sterndrive/mercruiser/45l/

I have a 2017 Bayliner VR5 with a 4.5l 200hp mercruiser engine. I noticed two things:
(1) Maybe its starting a bit slower than normal, like rrrr-rrr-start. As opposed to rr-Start.
(2) Three times at random while at idle the engine stopped. The electric system seemed to act up briefly then it cut out. Started right back up after like nothing had happened each time and ran again for days without issue. Then cut out again. Started back up ran for days without issue. Then again, started right back up and again ran fine.

Any thoughts?

 

[Rick Stephens]

Only thing I can think of is to clean up your connections, start at the battery, take em apart and wire brush till clean enuf to eat with. Pay particular attention to the ground wires. The one grounding ECM especially important.

 

[Lou C]

Agreeing with Rick here, your problem is likely between the boat wiring system (battery & cables) and the engine wiring harness (starter & alternator). If they used wing nuts to hold the battery cables on to the battery get rid of them and use either locking nuts or (my preference) buy a set of automotive style but marine grade clamps and bolt these onto the battery cable terminals. These then go on the larger battery posts just like on a vehicle. Then follow the negative cable back to the connection on the engine, it may be a stud on the bellhousing behind the exhaust system, make sure this is clean and tight. Then if you can get at it, make sure that the red + cable connection at the starter solenoid is tight; but before putting a wrench on that turn off the battery switch if it has one or disconnect the battery negative cable at the battery if it does not. You don’t want a dead short caused by a wrench grounding out on the engine!
ideally this boat should have a dual battery system....

 

[muc]

Agree that this sounds like a bad electrical connection.

Only thing i would add, the positive battery cable no longer goes to the starter. It has a dedicated power stud on the engine.