Yamaha F200 Bogging down after water in gas

[Nondeductible Expenses]

Looking for some advice on where to look next. This motor is driving me crazy.

I've got a 2009 Yamaha F200TXR, around 1,000 hours on it.

In August I had to get towed in because the engine wouldn't crank. Mechanic said fuel was full of water (was ethanol gas in tank all summer). Drained the tank, new Fuel water separator on transom, new engine mounted fuel filter, changed the filter between Low Pressure Pump and VST, changed VST High Pressure Pump screen.

Replaced gas with ethanol free and it now cranks and idles. I took it out and it will crank fine now, but after a while it will start idling roughly and also will bog down if I try and give it throttle. Can't get it to go over 2200-2400 RPMs without it bogging down. If I give it WOT it tries to die almost like it's drowning (or starving, I suppose).

Anyway, the only thing we hadn't cleaned in the fuel system were the injectors so I just sent them off and am picking them up today. I was expecting them to be dirty but the guy said I was only out of spec by 4-5% and they weren't that bad. He put new screens in them too. I will be able to put the injectors back in tomorrow and go for a test run hopefully, but I'm not very optimistic this is the problem if they were only 4-5% out of spec.

Seeing as I have basically gone through the fuel system and changed all the filters, vst screen and now injectors (which I now don't believe to be my problem). I'm going to pick up a fuel pressure gauge on my way home from work today and see what my pressure is at the rail while I'm running it this weekend (after I put the injectors back in). Probably should have done this before I sent the injectors off - oh well.

Oh yeah and all the spark plugs are new. What would cause the engine to lose rpm and basically almost die once I'm over 2200-2400 RPMS. I basically have to come back to an idle to keep it alive.

Also, when I'm idling I notice in reverse it gets worse, but I can turn the engine off and restart it and have a smooth idle for a little while. This makes me think it may be something electrical?

[rodbolt17]

not a relief valve issue.
either the injector screens are clogged, or the fuel pick up screen is clogged or you still have debris/contamination in the fuel system.
welcome to my world.

[99yam40]

Yea, draining the tank is not enough if it was full of water and bad gas

[Nondeductible Expenses]

not a relief valve issue.
either the injector screens are clogged, or the fuel pick up screen is clogged or you still have debris/contamination in the fuel system.
welcome to my world.

That's what I am thinking. I'm going to put the cleaned injectors in today and while I'm at it, I'll pull the pickup tube from the gas tank and see if the screen on the end of the tube is all gunked up.

I also just noticed a small crack in the hose where it attaches to the primer bulb. Might as well fix this while I'm at it. Some days I really wish I didn't like boats so damn much!

[Nondeductible Expenses]

Well, it wasn't the injectors. Put them back in with the new baskets and it didn't make a difference. Also, just pulled my tank pickup and it was just a tube with a diagonal cut on the end (I'm assuming so it wouldn't sit flat on the bottom of the tank) and no screen. It appeared clean and so did the antisiphon valve on top of the tank.

Haven't had a chance to pickup fuel pressure gauge yet to see if fuel pressure at the rail drops when the engine bogs down at WOT. Will try to do that this weekend.

One thing I have noticed is when it starts bogging it will backfire every now and then. That's likely from the lean condition from fuel starvation.

Also when i'm moving around the dock to put it back on the trailer it will start spitting and sputtering at idle and occasionally die. I can recrank it everytime and it'll idle smoothly for a few more minutes. I'm thinking this may be related to the relief valve (if the relief valve isn't working, the VST could be running dry until I recrank and it kicks the LP pump on and refills the VST?)

What I'm going to check this week/weekend:

1. Rail Fuel Pressure at idle and failure RPMS and when idling roughly (most important - if this is OK then back to the drawing board)
2. check each fuel line connection to make sure they aren't loose
3. Inspect fuel line conditions under cowl (ones on boat appear to be ok)
4. Check relief valves by LP Pump and one between fuel rails for damage from ethanol/water
5. Recheck VST Screen for more garbage since last cleaning


Any thing else I should look at in the fuel system? Would the Throttle Position Sensor, ISC(IAC?) valve contribute to any of this?

I pulled the ISC valve off and the plunger tip was carboned up, cleaned it with carb cleaner and it appears silver again. One thing I wasn't sure of is if I should be able to push the plunger in manually with my hand while cleaning it. It had no give to it, makes me wonder if it's stuck.

Thanks for the help so far!

[Nondeductible Expenses]

not a relief valve issue.
either the injector screens are clogged, or the fuel pick up screen is clogged or you still have debris/contamination in the fuel system.
welcome to my world.

Well Rodbot17, I eliminated the injector screens by getting them serviced and new screens, fuel pickup wasn't the issue.

Had to sit on the boat a while because other expenses came up that had priority (wife new tires, new ROOF on my house - ouch, etc) and now have the boat back in a shop with a different mechanic.

The initial compression numbers freaked me out so I had the shop perform a leak down test and all are within spec. That made me feel better as I feared I had some larger issues other than fuel system.

Shop just called me and said they pulled a fuel sample of the tank that had supposedly been "drained" by the other shop and it was again full of water. They are having a company come in and pull the deck plate off the boat and then clean and polish the tank to ensure 100% of the moisture/water is out.

He said my particular boat (2009 Sea Hunt Triton 220) had an issue with gas caps sitting in the recess on the gunnel and water can get into the tank that way so he's going to add a modified gas cap that extends the opening above the recess. Also said my new spark plugs had one of them fouled out and that my thermostat is stuck open so he's going to replace the thermostat.

Once tank is cleaned, they are going back through the fuel system with new filters, etc and cleaning everything out again. It seems the last mechanic changed the filters, drained the tank, but there may have been more moisture in the tank he didn't get out and it screwed up my fuel system again.

Hope this fixes it for good....

[boscoe99]

Keep us posted please.

Thanks

[rodbolt17]

yep, gotta love the rain.
just finished a Carolina skiff that was "fixed" last june.

after it ran rough then failed to start , they brought it to me.
after pumping almost 3 gallons of water from the tank and flushing the fuel system this F115 hits 5800 RPM anytime I wish.

the issue? was a leaking perko vented cap assy.

replaced it with a better desined one and off he goes.

why the other shop missed it, I dunno.

[Nondeductible Expenses]

Well Mechanic called me and said he's taken it on 2 separate test drives and steady getting 5,600 RPMS now. Picking it up tomorrow.

Since I found threads online helpful and hated when the OP didn't come back and post what fixed the problem, I'll list what all was done for someone having similar symptoms.

1. Water was in fuel from leaking gas cap - Gas cap modified to prevent future leaks.

2. Gas tank was professionally cleaned and drained to eliminate all gunk and moisture. Dealer Mechanic called outside company to perform this service.

3. New Fuel Water Seperator

4. All Fuel Filters replaced

5. VST tank cleaned, VST screen replaced, Fuel pump bench tested and was OK.

Basically, first mechanic changed all the filters and cleaned VST properly, but since tank was still gunked up all it did was reclog. Plus source of water was gas cap leaking so hopefully we've addressed the source and wont have problems now.

All in all, I've spend close to $3,000 on this and a few months of down time.

Why do I love boats again????

[rodbolt17]

yep
clean the fuel system at breakfast.
reintroduce contaminated fuel for lunch.

guess whats for supper .

[bajakeith]

Mec/Tec ???

Amazing how many part changers out there calling themselves mechanic... a fuel system is like the blood in your body,,,,put drugs in (water) and you have to clean the whole system from tank to the carb/injector and purge..purge and purge again !! the fuel system before hooking it back up (Duh) I have seen bugs,rubber and a host of stuff that you could easly miss if not doing it every day for a long time,,,Sigh ! with the big E/// I see fuel issue's every day in the calif. market and have merc TSB to the ca dealers warning that the gas can now be bad in 15 days !!! and have myself seen it in around 30.... Yikes !!

[Nautical]

Do you have that Merc TSB ? that's interesting !.. Thanks

[bajakeith]

Nauti

TSB=Tech Service bulleten... has very little to do with what company put it out,,simply the fact that we are getting screwed with ethanol..and the gov knows about it and they will not let it be sold at small aircraft airports..But, you can buy it and put in your chain saw,,weedwhacker,,lawnmower,,Truck,,car,,boat.. your car/truck gets used..any thing that sits is gonna have issues..I myself see the problems of the big E daily..the same ole big gov BS !!

[bajakeith]

Wtf

Never had a post go into nowhere

[boscoe99]

Rube ****berg. Just testing