2013 F150 loss of RPM WOT

[panasonic]

I would get them to do a leak down test..or at the very least a compression test before anything else...check the general health of the engines heart.Easy and quick to do and cross that off the list.

[Neversosure]

Taking boat to dealer after holiday........ stay tuned

[Neversosure]

The manual I found online was for a f150A, the manual tells you fuel pressure specs..... https://www.manualslib.com/manual/95...a.html?page=76

I also checked the fuel regulator as well and that is functioning as it should,

I guess I'll haul it out of the water and send it to the dealer......... THANK YOU EVERYONE FOR THE IDEAS AND SUGGESTIONS!!!!

STAY TUNED, I'll post back in a week or two when I something is found!!!

THANK YOU AGAIN!!!!!

[TownsendsFJR1300]

well now that I think more about this, It probably was not rail pressure I was thinking about.
maybe lift pump pressure on some other motor

The manual states how to check(Schrader valve), but I don't see any pressures. I'd think it'd be there, but I'm missing it...

[99yam40]

well now that I think more about this, It probably was not rail pressure I was thinking about.
maybe lift pump pressure on some other motor

[TownsendsFJR1300]

maybe Townsends can comment of the fuel pressures.
I thought it was different than 40 all of the time.
he should know

I don't see spec's for the pressure in the Yamaha shop manual. Fuel does go thru a regulator BEFORE the rail...

PM sent to the OP

[99yam40]

maybe Townsends can comment of the fuel pressures.
I thought it was different than 40 all of the time.
he should know

I second the test wheel thought

[Neversosure]

Fresh bottom paint, no more then a coat and the barrier
,

boat is 100% composite, no wood.

boat is 4 years old.

[99yam40]

fresh bottom paint means it sits in water a lot,
could the paint load up a motor some?
did it have bottom paint before?

does that boat have any wood in the hull?
stringers and transom.
no free water does not mean water has not soaked into wood inside the hull.

[Neversosure]

Changed the thermostat, the old stat didnt look too bad, I will take it home and toss it in some hot water.

checked fuel pressure at the rail, 40lbs +/- key on, Idle 40lbs +/-, 40lbs + at load wot.

Ran it same thing 5300rpms, I did play around and try to trim it up and did get it to 5500rpm but had dolphining going on and the rpms bounced to 5900rpms when motor trimmed up, but still not the top speed of 41 mph that I had.

pulled each plug wire 1 through 4 to see if I had a miss, no miss.

Last year the boat would run 5800-5900 rpms with little or no trim, still has power loss somewhere.

the hull is a 2015 Defiance 220ex.

gonna pull the prop have it checked as well, the prop has no vibrations or dings in it, but indont know what else could be the issue.

no added weight to the boat, no hidden water in the boat.......

stumped.

[pstephens46]

Would be an ideal time to find and use one the unicorns that Rodbolt talks about. The infamous test wheel.

wonder what hull is being discussed?

[99yam40]

rail pressure would affect all of the plugs not just some,
but it is a good idea to make sure the pressure is in spec and stays in spec at all RPM.

what injectors did you get to replace the old?
did you send off the old for servicing to keep as spares?

might swap them back if they checked out good after cleaning.


how old is the fuel?

[Neversosure]

I am going to the boat today, I ran the boat last Sunday, I will pull the plugs and look at them again, the boat was running fine then started this issue last summer. I did all the work this winter before taking the boat back down again last week.

no there was no prior repair to the engine before this issue started.

[Neversosure]

I replaced the four injectors th is winter, I believe the bottom 2 plugs were sorted #3 & #4.

[TownsendsFJR1300]

Which plugs were sooted up?

Prior to the issue, was ANY maintenance / work done to the engine?