2011 40hp issue?

[Jmurphy1]

I've got a 2011 40 hand tiller, fuel injected. I've had some intermittent problems over the summer and now seems to be getting worse. When I leave the ramp it seems to run fine. The problem seems to arise when I go to run somewhere else. The motor starts and idles fine but when I give it some throttle it seems to either not be getting fuel or not taking it. It won't get on plane and the rpms go up and down. Doesn't seem to get over 3000-3500. I usually can get it to clear up by cutting it off and pumping the primer bulb (mostly because I don't know what else to do). Pumping the bulb while running doesn't seem to clear it up. I've always added ring free and the fuel stabilizer/conditioner to my gas.
Any ideas?
Thanks Jason

[Jmurphy1]

Anybody?
Thanks

[pstephens46]

Fuel issues. Has this motor been sitting unused for a period of time? Do you use ethanol or marine gas or both? If you are pumping ball with no results I am guessing fuel issues after the VST. High pressure side. There are filters in VST that can be clogged. Maybe Rodbolt will weigh in.

[Jmurphy1]

It hasn't sat for more than a few weeks since early summer. I do use ethanol gas but I've always put stabilizer in the fuel and if the gas started to get close to a month old I would dump it out and buy fresh.
I'm by no means a mechanic so forgive my ignorance, what is VST?

[cpostis]

It hasn't sat for more than a few weeks since early summer. I do use ethanol gas but I've always put stabilizer in the fuel and if the gas started to get close to a month old I would dump it out and buy fresh.
I'm by no means a mechanic so forgive my ignorance, what is VST?

I agree with pstephens.

VST is "Vapor Seperator Tank". In your motor it is referred to as "Float Chamber Assembly" (FCA)(#1 on the diagram in the attached link). The filter pstephens refers to is # 19 on the diagram. It takes a bit of mechanical aptitude, as you may have to remove the FCA, separate the body assembly from the cover to check/replace the filter # 19.

http://yamahamc.partsandwarranty.com...1665040&Page=1

If it is a fuel issue, it can be anywhere from your tank to your fuel injectors. (I'm assuming it is a portable tank). Your fuel pick up, engine mounted fuel filter, VST/FCA filter, or (unlikely) fuel injector filters may be partially clogged. It may even be that your fuel tank is not vented properly (vent screw closed, improper fuel cap etc.)

A mechanic would probably check/monitor your fuel rail pressure at the problem RPM.

You should get an appropriate service manual if you take this task on yourself. Yamaha manuals are not very procedure friendly, but show most all specifications. I find the Seloc manuals much more procedure friendly.

Have you had a full maintenance done recently? Maybe it's time for a full periodic maintenance service by a dealer for your motor?

Also, please provide your entire model number of your motor (F40JEHA, for example) , others may respond more favorably.

[pstephens46]

Good info Chuck. Been in meeting.

Ethanol issues are not prevented by stabilizer based on my experience. It helps but in no way compares to using straight marine fuel with NO stabilizer. Use marine fuel if available all the time. Your 40hp gets great mileage anyway and will save you lots of aggravation and money in the future

[cpostis]

Non-Ethanol Gas Station Locator

Good info Chuck. Been in meeting.

Ethanol issues are not prevented by stabilizer based on my experience. It helps but in no way compares to using straight marine fuel with NO stabilizer. Use marine fuel if available all the time. Your 40hp gets great mileage anyway and will save you lots of aggravation and money in the future

I always use non-ethanol in my Yammy and other motors! Here's a great link to locate non-ethanol gasoline.

Ethanol-free gas stations in the U.S. and Canada

Meetings... Uhhhh! My last five of 25 years working for City of Miami spent more hours in meetings and giving testimony about corruption than performing my job duties as Superintendent of Property Maintenance. So glad I'm now retired!

[Jmurphy1]

The motor is a F40LA according to the sticker on the motor. I've changed the oil & filter, fuel filter, fuel water separator and lower unit oil every year myself.
I guess after I get this straight I'll find some ethanol free gas from now on.

[cpostis]

The motor is a F40LA according to the sticker on the motor. I've changed the oil & filter, fuel filter, fuel water separator and lower unit oil every year myself.
I guess after I get this straight I'll find some ethanol free gas from now on.

Good, so your are somewhat mechanically inclined. Do you have access to a fuel pressure gauge? Do you have a service manual? If you have these, it is not very difficult to check your fuel pressure and check VST/FCA filter, I bet it is the filter.

[pstephens46]

Good, so your are somewhat mechanically inclined. Do you have access to a fuel pressure gauge? Do you have a service manual? If you have these, it is not very difficult to check your fuel pressure and check VST/FCA filter, I bet it is the filter.

Correct me if I am wrong but that filter inside VST can be cleaned versus replacing.

[cpostis]

Correct me if I am wrong but that filter inside VST can be cleaned versus replacing.

Can be cleaned if no tears in the mesh.

[Jmurphy1]

Yea I'm somewhat mechanically inclined just not a mechanic. My dad was a helicopter mechanic. I've always done most general maintenance on my stuff mysef. However I'm a little leary of doing to much to this motor because I know it will be expensive if I screw something up.
I don't have a manual or a fuel pressure gauge. I can buy a manual and might have a friend that has a pressure gauge that would probably help me.
How big of a job is this? What's the best way to clean the filter if I can get to it?
Thanks for the help

[Jmurphy1]

I looked for Seloc manuals on amazon but didn't see one for anything newer than a 2010. They were pretty expensive.

[rodbolt17]

dude
m pay attention.
it is self explanatory.
remove the intake.
remove the VST.
open and close the VST
reinstall everything.
god
I gotta buy a monkey.

Yamaha electronics rarely fail, fuel systems clog up.
fuel systems clog on all brands.

[pstephens46]

And now, sir, you have met Rodbolt!