On Friday, was running in the backcountry of the ENP. Ran around a bend, shallow water, but plenty of depth for my boat. Motor acted like it had hit a soft bottom and then cut off. Had trouble starting it and then once I did, would not run under load. Ran at idle speed for a while, then increased the speed. Motor seemed to run fine the rest of the day, though was worried about running too far from Chokoloskee just in case… Motor was serviced in the last serval months, fresh non-E fuel. What could have caused this?
Check filter and lines for anything that would constrict fuel flow.
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Yea I’d dump the fuel filter and separator In a jar. See if you have any trash in the gas. My old v max used to do something similar and it was always the VST filter clogged up.
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Did it get hot? I had an etec sometimes it would get hot and go into safe mode then eventually cool down and let you go full throttle
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If I was going to guess this is the most likely cause.
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Had a tohatsu 60 not long ago do the same thing with bad gas. it was fine at idle and low rpms. Would cut itself off after making a short run. Had my tech drain the gas and she ran like a top right after.
Never got hot or heard an alarm
I will add those fuel filters can look fairly clean and still cause an issue, my New 250 yammy ran great, then after a few trips It would run fine at idle but when I open it up it would run just long enough to get on plane then cut back like you pulled the throttle, so i took it to the shop! They found a small filter on top of motor was the issue it was a small filter like 3 inches long by maybe one inch in diameter it looked clean to the eye all but a lil what looked like pepper in it….I guess it was some of the old gas hose IDK but after that no more problems 
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I had the same issue on my F70 about a month ago. Clogged fuel filter. Start there for sure.
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Dave, possibly vapor lock? I’ve been in similar scenario.. open the fuel fill to vent briefly and once closed, prime your fuel bulb until hardened.
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Check your anode on the water jacket.
I have gotten bad gas twice, both times were “ethanol free” that had tons of water mixed in.
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That sounds like a clogged fuel filter, or a little water on the fuel. I would check filters first.
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I’m think it was this. Ran fine the rest of the day. I’ll find out for sure this week as I’ll be back on the water for two days.
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The fuel filter on the back under cowling has a black ring in it that floats if there is water in the fuel. It’s in the engine break in section of the owner’s manual.
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Did you cycle the key off then on to attempt restart or just hit the key to start again? Sometimes when a fault is detected such as an overheat cycling the key will allow the ecm to sorta “reset” unless the engine is hot. I will say your situation does sound more like a fuel delivery or quality issue though.
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A long shot but worth adding to the check-list. Is the gas tank ventilation partially blocked? If there’s a clamshell cover on the overboard vent, did a Mud Dauber built a mud-nest there?
I had a similar problem with a previous boat when the EPA Carbon Canister got saturated with fuel and blocked proper ventilation. Same problems you’re experiencing. Fuel prime bulb was collapsing.
May not be your problem but worth thinking about. I believe fuel flow problem is likely the cause, as mentioned above.
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Thanks, Mac. I’ll take a look.
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Thanks, but doesn’t seem to be.
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Interesting. I am praying mine doesn’t give me any trouble, I’m on 23.5 hours, about to change oil, filter and lower unit lube.
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