Got extremely busy with work this summer and the boat sat for about 3.5 months. I hadn't planned on her sitting, so no preparations were made for it. Maybe 1/4 tank of fuel.

About a month ago I was home for a weekend and had all the stuff, so I did the oil change, impeller, fuel filter, separator cartridge, basically all the stuff I do to her every year. All Yamaha parts. Ran it on the muffs for about a half hour to circulate some fuel through it, and put her back up.

Last thursday I decided to take her out for a couple of hours in the evening. Stopped and put $20 of fuel in her, and headed to lake. Cranked as expected, idled out of the marina without drama, came up on plane and as soon as I started trimming up she fell on her face. Reduced to an idle immediately, a noticeably rough idle, and made my way back the ramp. Loaded up and came back home. With a busy schedule on the horizon, with a much needed vacation in a couple of weeks. Knowing the shops are backed up I went ahead and took her in since I don't know if simply replacing the fuel would fix it, and a looming work schedule ahead.

As I was idling back tot he ramp the motor had moments where it acted like it wanted to go, but very briefly.

It's a 2013 Yamaha F70. Always maintained, sea-foamed every other tank, never given me a second of trouble, just neglected this one time. Water pump impeller even looked like I could have gotten another year out of it. Good water pressure, according the gauge I put on it. No alarms.

So how bad is it? Stuck injectors? Just replacing the fuel? Anything else?

I'm praying it's something pretty easy, so I have the boat back in time for my vaca, and of course so it doesn't cost me an arm and leg.

bad fuel.
johnny

yep fuel, exact same thing happened to me last week,, pretty much word for word. Motor ran just long enough to get out into the lake then we were dead in the water. Pulled the cowling,and unscrewed the fuel filter, pumped a gallon of "bad " fuel off the bottom of tank. Ran again, like it never happened. Made the rest of the trip,, ran for the next four days, got home and dismantled fuel filler neck and sucked every drop of fuel out. I ran mine on muffs also the day before we left.
ETHANOL IS THE DEBIL. even with stabilizers.

My fear now is, did all that missing and running rough and backfiring when it was trying to run damage anything? Like I said , ran fine after getting some of that [censored] out?? So maybe no??

I'm hoping that the VP fuel station that is going to open here has non ethanol.

Bad fuel. They will have to chase the water out from the tank to the injectors/carbs. Even with ethonal free gas you will still get water in your fuel if you leave it sitting with for that long with a little gas in the tank. It's best to neither have it empty or full. The heating/cooling cycle from night to day during humid conditions draws water in.

Injectors?

Injectors, specifically #3 was misfiring. They pulled them all and cleaned them, drained the fuel and replaced all the filters.

Of course, then they proceeded to change the oil, impeller, lower unit oil, plugs, etc, doing a full service on it. Great, if I hadn't just done that a month ago, and told them I did when I dropped it off. The guy claims to have misunderstood me, thought I was requesting it. I wrote the dates on the oil filer and water separator cartridge, couldn't believe they didn't notice that and call me. I bet they thought, "man, this thing has the cleanest oil and lower unit lube we've ever seen, and the impeller looks new. Even the plugs look new, except this one in the 3rd hole". SMH!

They did turn it around in just over a week though.

Where was this?

So,I wasn�t going to out them over a miscommunication on the work I wanted vs what they did. Seemed like it could have been an honest mistake.

I want to setup the following experience by saying, the last thing I asked the shop as I walked out of their door to leave was, � so I am OK to haul this boat to Arkansas next weekend and it�s going to run right and not give me any problems, right?�
The guy�s response was, �yes sir�.

FF to today, took the boat to the lake for a test run. Cranks and idles great. Unloaded it, tied it off while I parked the truck. Idle out of the marina, put her up on plane and trim it up. Running fine til I get about 1/4 mile in the main body of the lake and it falls on it�s face and dies. Crank it, runs for a couple seconds and dies. I gave up after it did it the third time and threw the anchor out.

After I got anchored up I went back and squeezed the primer bulb and was soft, never have EVER had to squeeze the bulb on this engine. As I�m pumping on it I here it sucking air under the back deck. Lift the hatch, squeeze it somemore, and reach in to feel around where the sound is comng from. I discover ther is no cartridge screwed on the water separator. Look all around the bilge, it�s nowhere to be found. Not one in the boat anywhere.

So now I�ve paid for a service I told them had been done less than a month ago, but if I had watered down fuel I can even understand how that might have been needed to be replaced given the problems I was having. But then to get the boat back with the assurance that its good to go, then get it back like this?

Luckily I had enough tools on the boat to bypass the separator and get her under way again and run it around. Otherwise it runs fine. Will be ordering a separator cartridge, and put this experience behind me. Will never take my boat back there again.

Even if you decide not to out them they need to hear about that. Could have been a new guy, could have just been sloppy. They need to pay you back on the labor they billed you to r/r that filter. They left you with a fire hazard. Could be an honest mistake but they should make good on it for you.

Agree. Unlike most people, I fill my tanks after I use my boat, equipment, or whatever. Just works better that way, when it is time to use it again...

Sometimes my boat will sit for 6 months. I have NEVER had a fuel problem. Ethanol is not the best choice for fuel, but it IS NOT as bad as some want you to believe.

I just went through what you are dealing with .
My fuel was E-10 and went through the whole phase separation .
I was having troubles getting that last few drops of water out of the tank so I installed a "Racor 120AS Fuel Filter Water Separator" .
It has a clear bowl with a drain so I can see the water accumulation and just use the drain valve on the bottom and a gator aid bottle to keep the water out of the carb .
Then I can dispose of the water / fuel mixture safely and I'm not left stranded on the water .

I can go through your fuel system and get injectors clean and replace all fuel filters.