350 mercruiser mpi won't start - video

[Formulaz]

Well it was the cap and rotor!

I inspected them in the very beginning of this problem and they looked pretty descent so I just moved on. Plus they were replaced 'recently' meaning 2 or 3 seasons ago. Anyway one thing I did notice this time is the screws that hold the cap on felt like they were getting tight when in fact they weren't. It is possible that the old cap had some play in it if I wasn't careful during install last time. I would check/replace the cap and rotor very carefully if you're having similar problems.
Oh also - before I replaced them I pulled the cap off and the engine turned over smoothly indicating that the abrupt stopping during cranking was indeed a misfiring cyl.

I hope this helps!


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[JCP]

I would still replace the plug wires. You could have an open (high resistance wire) that could have contributed to your premature cap and rotor failure.

[Formulaz]

Oh really? Ok good to know. Boat ran great today - surfed about 3hrs and it ran flawless


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[Joehs]

Well it was the cap and rotor!

I inspected them in the very beginning of this problem and they looked pretty descent so I just moved on. Plus they were replaced 'recently' meaning 2 or 3 seasons ago. Anyway one thing I did notice this time is the screws that hold the cap on felt like they were getting tight when in fact they weren't. It is possible that the old cap had some play in it if I wasn't careful during install last time. I would check/replace the cap and rotor very carefully if you're having similar problems.
Oh also - before I replaced them I pulled the cap off and the engine turned over smoothly indicating that the abrupt stopping during cranking was indeed a misfiring cyl.

I hope this helps!


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This is great news! I have a new cap and rotor in order. I checked mine two days ago and every lead was severely corroded. Just decided to order replacement parts and be done with it knowing it needed it anyway. Will report if that fixes mine as well! Glad you're back on the water, I'm itching to get mine out next week!

[Joehs]

If anyone is searching for this, a cap and rotor also fixed the same issue I was having. Hardly turns over at all now and fires right up. Cleared up my rough idle as well.