Mercruiser Engine cutting off out of nowhere ( great to know stuff)

One day heading down the channel one of my engines Kept shutting off out of nowhere, you won’t believe what it was! With a little bit of luck we figured out what it was. Sometimes MerCruiser problems can be tricky especially with intermediate problems.

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[BSwift-os]

Thank you very much for this suggestion! My port side cuts off for a second under way, along with the gauges so I will check this and also replacing start/ignition switch (370DA Inboards).

[brianyechout]

I have something similar going on. It only happens when I’m above 3, 700rpm, the motor goes off then back on like flicking a light switch. I’ve been going crazy as this thing has run flawlessly for the 10 years I’ve owned it. Thanks for giving me something new to check.

[jimcatanzaro]

Buy the manual book for it u need to get rid of the stator first off and replace the seals for the water pump in the front of the motor

[gcalda]

Mine dies after it’s warm, usually on the way out, just stops. Replaced ignition coil, still happens, only when warm, usually starts right up again, but only runs a few minutes, I’m thinking vapor lock? Online filter and water/fuel filter replaced… still no go, electrical or fuel?? It’s a 4.3 GMC OMC Four winns 1988 with 137 original hours

[shanetyler]

Yeah mine will start and run at low idle when cold. then after running on the water for awhile when put into neutral it will die and not restart.i believe its a IACV idle air control valve.

[direstrait]

Hi, why do you have a cracked cylinder head? I have same engjnes.

[hakansundberg]

I had the same problem but it was wrong with my killer switch

[timothyhelf]

Had the same problem on 2 boats now, original fuse ir fuse block, very anoying

[codyjames]

Took it in salt water for the first time- came home and flushed it dies about 10 minutes in. Open the motor compartment and it’s smoking. No clue water was on it