Couple of issues with F40LA (2011 EFI 4 stroke)

[james_f_nc]

New to me 2011 F40LA. First boat.. bear with the newb questions.

First of all, took it out for the first spin and wasn't getting anything out of the tell tale. No overheat alarms so I slowly made it back to the ramp. Turned out to be a clogged tell tale. Healthy stream after reaming the tube. I'm thinking since it seems to be pumping fine that no damage was done.

Then I had the buzzer go off in neutral, no buzzer in gear. Believe this to be (water/fuel separator) in engine looks fine.. possibly bad sensor. Disconnected sensor and restarted.. no buzzer. Looks like you have to replace the whole cup to replace the sensor?

Most pressing issue.. intermittently if I'm idling along and go WOT throttle to get on plane.. had some bogging at ~3000 rpm where it just falls flat on its face. Idled and repeated the falling on the face a few times then eventually it will get up on plane and runs like a top. I am running ethanol free however have no idea of prior owner history.

Checked with the prior owner's service marina.. they advised the fuel pump bulletin was addressed but didn't give a wealth of information.

I thought about replacing the pump (looks to be about ~80 bucks or am I looking at the wrong part.. anything else I should replace while I'm at it?)

Currently dropped it off at a shop to have the fuel filters replaced.

[TownsendsFJR1300]

IMO, run Yamaha "RingFree" regularly; https://www.yamahapartsandaccessorie...?b=Search&d=34

Right now I would run 2x-3x the amount for your issue. It won't hurt anything. If there's some crap built up in the fuel system, it'll help take care of it.

Use fuel stablizer as well. The gas is crap nowadays..

As for the fuel pump, etc, IDK, someone else will chime in.

[james_f_nc]

Thanks for the tip. Will pick some up today.

[james_f_nc]

So I took the fuel filter cup off. It was half full of water when I poured it out.

Aside from changing the fuel filter and swapping to a new clean tank and flushing the fuel line out. Anything else I should do that is more intensive (take apart VST) etc that would necessitate a shop looking at it.

[TownsendsFJR1300]

There is a drain screw (phillips)on the bottom of the VST(and maybe a hose).

Put a clean tuna fish can under it and drain. Inspect for water.

Prime the bulb more until it comes out clean. You can(if a hose is connected, blow gently back into it by mouth) to bubble up/loosen up any crap in there. Very easy to do, just be careful...

Once you can get the fuel/water out of the lines you should be good. I'm Not sure if you have a drain(think you do) on the injector rail. If you do, drain as well..

Please post back


The drain hose on mine is just to the right of my yellow dipstick;

[james_f_nc]

Got the fuel filter swapped. Swapped to a new tank with new gas. Drained a few ounces out of the VST. Got a little water. Pumped the ball and let it continue to drip drain until it seemed to be just gas.

How smooth are these 4 strokes supposed to be? It's got a fair shake to it in idle.

[TownsendsFJR1300]

The one I checked the valve adjustment on, shook a pretty good amount.


My F150 (in-lint 4) is pretty darn smooth, his 40, single carb, 10 x's shakier.

Others will chime in with their experience..

[james_f_nc]

I really appreciate all the help. I'll take her for a spin this afternoon and see if this cures the issues.

[TownsendsFJR1300]

we're you able to pick some Ringfree?

[rodbolt17]

once you run it a bit it will clear the VST and rail from any other water.

the pump doesn't care whats pumped and the injectors don't care whats sprayed.
if there is enough gas in the VST,even mixed with a small amount of water it will run.
if it will run and you quit adding water eventually it will clear itself.
that's the beauty of EFI.

[james_f_nc]

Yes I have it a double dose of ring free plus. Also threw in some of the Yamaha fuel stabilizer.

Thanks rodbolt! I think that was my main concern that without manually clearing all water I could cause some serious damage.

[james_f_nc]

Took her out today. Ran great, no hesitations or stutters.

[TownsendsFJR1300]

Took her out today. Ran great, no hesitations or stutters.

Excellent!! Keep running the RF, Its great stuff.

I run it in EVERY GAS POWERED machine I own.

If one starts acting up, 2 to 3x the amount of RF takes care of it.. No bad issues at all running it heavy, just on the wallet...

I'd still have my 2 stroke 150 Evinrude if I knew about RF back in 2007....

[MSmith1227]

It seems like you found your answer, and I hope you did. I would like to add for the benefit of anyone looking for help on an issue like this, I was having the same problems but this did not resolve my problem. My motor would do the same thing but it was always after it was at running temp and after I had either idled or run at low speed for any period of time. After trying all the above mentioned solutions, plus new hoses, primer bulb, filters and sending the injectors off to get cleaned I still had the same issue. It turned out that it was nothing more than a clogged water line in the fuel cooler that was allowing the fuel to heat up. It was a simple $0 fix that took less than 5 minutes to blow out. I just wanted to add my experience in the event there is anyone else scouring the internet as I was looking for possible solutions.

[boscoe99]

It seems like you found your answer, and I hope you did. I would like to add for the benefit of anyone looking for help on an issue like this, I was having the same problems but this did not resolve my problem. My motor would do the same thing but it was always after it was at running temp and after I had either idled or run at low speed for any period of time. After trying all the above mentioned solutions, plus new hoses, primer bulb, filters and sending the injectors off to get cleaned I still had the same issue. It turned out that it was nothing more than a clogged water line in the fuel cooler that was allowing the fuel to heat up. It was a simple $0 fix that took less than 5 minutes to blow out. I just wanted to add my experience in the event there is anyone else scouring the internet as I was looking for possible solutions.

Good point. Thanks for taking the time to post this information.