115 hp merc not accelerating

[Mike10gs]

Hey everyone so i tried to take the boat out and see if the engine was running right. It started up fine warmed it up and on i went. After passing the buoy i tried going faster and it did not want to. Alnosy like wanted to choke and die which it did after a couple minutes. Started up again and waited a bit till i put it in gear and it went but slow. So i came in. Anything that i can do before going to a shop? It did sit for about 4 months. Carb? Any help will be appreciated. Thanks

[Onmygame]

Could be a myriad of things, from carb, rest of fuel system to impeller.

One of the easiest things to check is if the motor is cycling water - a small stream out of the back of the shaft indicates the impeller (water pump) is functioning and the motor not over heating.

It is a part that they say should be replaced every two years, and if not performing properly the motor will bog down and seem like it isn't getting fuel when too warm.

And then there is the carb / fuel system.....many, many possibilities there.

The best of luck!

onmygame

[SalmonAddict]

based on what you have said so far, going with onmygame's response should be a good start.

the symptoms you mentioned sound like its overheating and not getting cool water. if you are not getting water, then bingo. impeller swap and maybe water pump swap should do the trick. thats the small end of it.
the heavy end might be if something is clogging the water passages (broken off impeller blade, or debris) now yeah that takes a little more of a teardown in a way.

but if your outboard is "peeing" a stream of water then move on to the carburetor, fuel, etc

[Amx]

water pump is covered, so;

the carb might be varnished up, or sediment from the ethanol crap in the gas.

spray the inside carb real good with carb cleaner, or Spray Sea Foam to get the varnish out of the carb. Put the proper amount of Sea Foam liquid in the gas tank, as per the directions on the can.

if it doesn't have a carb, and is injected, spray it anyway, if that doesn't work - take it to the shop

[Mike10gs]

Thanks guys for your quick responses. There was water coming out fine. I did look for that while was out. I was also thinking of the gas and sitting there for a while. Will go get some carb cleaner and give that a try. It has 3, should i spray all? Its a 6 cyl. Dont know if i gave enough info on the outboard.

[Amx]

Yes, spray all 3 of the carbs.

[Hunter757]

What year is your motor? Also are you running no ethanol fuel or just regular pump gas? How old is the gas your using and did you put any stabilizer in it at the end of season?

[Mike10gs]

When i spray the carbs, should i do it while on or before turning it on. Thanks again so much for the help.
Hunter757- it is a 79. Regular pump gas (usually shell). Whats the difference? The gas was sitting for about 4 months. I bought some liquid i forgot what its called it has 360 on the front. I put some of that yesterday which was only about 1 gallon left. Then put 4 gallons of fresh gas. Was that a bad thing to do?? And i forgot to put stabilizer at the end. I know really dumb of me. Thanks for the help.!!

[Amx]

Spray the carbs while the motor is NOT running. Let it sit overnight. Spray again in the morning. Let it sit while hooking up a garden hose to the muffs for cooling, or take it to the lake to run it.

[Juniah87]

There is a difference. If your Shell has a sign on the pumps that says "May contain up to 10% ethanol" this may very well be your problem as well. Ethenol is hydroscopic, meaning it will absorb water from the air, from condensation inside your fuel tank, pretty much anywhere it is available. If you do not add additives specific for protecting engines against water in the fuel, it can damage the engine. Also, ethenol is a pretty powerful solvent, and 2-strokes are known for getting sludge buildup. The ethenol can dissolve the sludge from where it is stuck in the fuel system, and transport it to various areas of your engine which can also cause damage. You should be able to find a gas station that has ethenol-free gas. I believe Cenex sells it? Since I don't own a boat I do n't know for sure, but it should be pretty easy to find one in your area with a google search.

P.S. Did this happen at Long Lake in Kitsap County? Saw a very nice individual there who was having motor problems. He helped me load my pontoon in my truck. Saved me about 2 or 3 minutes of grunting and holding up boat launch traffic

[Hunter757]

So, yes the ethanol fuel will destroy your fuel lines if there the older style along with your gaskets in your fuel pump. Spray your carbs as stated above and try running your motor. If your problem still exist let us know. Something else is if you run the motor and it does the same thing, try pumping the primer bulb a few times before the motor dies. Good luck!

[Mike10gs]

Did not get a chance to go get some carb cleaner but will go tomorrow.
Amx - i will do exactly as you mentioned. Thank you

Yes the gas i get does say that. I had no idea. I will definately look for a different gas station. No i am in king county. Was out on lake washington by rainier beach.

Again THANK YOU everyone who gave me tips on what to do. Will be getting the carb cleaner tomorrow and then try with the muffs on.

Bummer was hoping i would take it to chelan on the 29th now might have to take my 12ft.

[Amx]

There is ethanol free gas at the Grange on Gilman Blvd, I think it's Gilman, the main street east to west not far from I-90, east of Front street in Issaquah, and suppose to be a station in Auburn with that gas.

[Hunter757]

http://www.pure-gas.org/index.jsp?stateprov=WA This should help you find one close to where you live. Let us know how the motor does.

[hewesfisher]

Not intending to ruffle feathers, but, DO NOT spray carb cleaner into carbs when the engine is off, absolutely DO NOT when it is running. You should never spray carb cleaner in a 2-stroke engine, it's a straight shot of solvent, without oil, right into the crankcase.

Spraying carb cleaner into the carb throats cleans the carb throats, but none of the internal parts where, if it IS a carb related issue, the real problem exists. The only way to accurately and properly do this is to disassemble the carbs, clean the internal parts (passages, jets, etc.), reassemble with fresh carb kits (stay away from aftermarket!), synchronize linkages, reset timing, and reset idle rpm in forward gear in the water.

How old is your fuel line and bulb? Are they Mercury lines/bulb? If so, what is the color of the lettering on the fuel line? If red, it needs to be replaced from tank to motor with new line including a new bulb. I do not recommend aftermarket lines or bulb, get the genuine Merc parts. Yes, it makes a difference.

It would be helpful if you told us a little more, how you prepped the motor for winter storage, how or if you treated the fuel, and when the spark plugs were last replaced.

Sounds like you are using a portable tank, and if so, dump all the fuel, start with fresh 87 octane, add 1oz each Merc Quickcare and Merc Quickleen to every 5gals. You could double dose the Quickleen and see if your carb issues clear up. If not, you'll need to pull carbs, clean thoroughly, and reassemble with new kits. Btw, Seafoam contains isopropanol, aka isopropyl alcohol, so if you're going to pay extra $$ for alcohol free fuel then why put Seafoam in your fuel?

I'm odd man out on ethanol fuel, I've run my Mercs on E-10 from day 1 and never a problem. Do I like E-10? No. Would I use it if I had a reasonable alternative? No. Is it prone to octane degradation? Yes. Is "pure gas" prone to octane degradation? Yes, just like E-10.

I always treat fuel with the two products recommended above and never add fuel without them. I know others will say it's worth the "peace of mind" to pay for ethanol free fuel but octane degradation occurs irregardless if the fuel contains ethanol. It doesn't "store" any longer nor any better than E-10, it just doesn't contain ethanol.

Fuel system cleaner and stabilizer should be in every tank if you know you won't use all the fuel within 30days. Merc's Quickleen and Yamaha's Ring Free are fuel system cleaners, and unlike Seafoam, neither contain alcohol of any kind. Merc's Quickare and Quickstor and marine Sta-Bil are all good stabilizers. Don't have any personal experience with Sta-bil 360, but don't think it will perform any better than standard marine Sta-Bil in your application.

My fuel "cocktail" (1oz ea Quickstor & Quickleen to 5gals) costs $.28/gal which is a lot less than paying the premium for ethanol free fuel. Mercury and Yamaha both recommend using stabilizer and fuel system cleaner unless you're running your fuel out in 15 - 30days and few of us do that.

My $.02.

[Mike10gs]

So i got one that said carb and choke cleaner. Bought it from outdoor emporium. I will put some on today then again tomorrow and give it a try. Now will be looking for non ethonal gas to try it with. Thanks again guys

[Amx]

As you look into the throat of the carb, you'll see small holes, spray the SeaFoam into those little holes to get the spray down into the passages as much as you can. Sometimes it helps to remove the fuel line from the carbs and spray into the fuel passage. And no you don't want to spray down inside the engine you are cleaning the CARB, not the engine.

[Bodofish]

Seafoam works great sprayed right into the carb but as you said, that's not really cleaning the carb, that's all the other carbon build up. if you can get the pickup tube into the can of seafoam and pump the bulb, awesome!! That'll get it all over inside the carb. Let it sit for a bit and then run the gas through it with about 50% seafoam. It's amazing what it will clean up.

[Sideburns]

All good advice here! The ethanol fuel you just added may not be the best for your fuel system parts, but may actually help suck water (dry) out of the fuel system and clean it some too, as long as you run it through and fill up with E-free soon!

hewesfisher-
My favorite is when people add Heet to supplement their E-10 fuel! Ive even heard mechanics recommend adding the little "4 oz bottles of alcohol" to the tank that's already 10% ethanol...

A good modern sealed fuel system is not too bothered by ethanol in fuel, but older systems that have open vents and leaky fuel caps etc.. suck water right out of the air (hyGroscopic) Once the ethanol content becomes about 7% water, the water cant stay suspended in the fuel and forces "phase separation". After the water/ethanol separates to the bottom of the tank and flows out into the rest of the fuel system, its likely over 90% ethanol! Now we have a major problem.... Many times in small fuel systems, I will see fuel lines/parts melt, only in the low points, which is a pretty good visual representation of what can happen.

When engines stutter and die after sitting over the winter, 9/10 times I'll find white powdery corrosion or particles of rubber lines etc.. in the carb plugging up jets.

This is usually only a problem in older or unsealed systems and/or extended storage, but that describes many of our boats pretty well! The stabilizers (Stabil) ive had experience with have been useless against this ethanol fuel phase separation problem, so I'm skeptical of stabilizers... but hopefully those marine stabilizers better?

....my 2 cents...
-Sideburns

[Sideburns]

Also, once this alcohol water mixture has separated, the rest of the fuel is now mostly ethanol free right? Yeah, maybe, but the ethanol was responsible for a lot of the octane rating of the fuel. Without the ethanol, E10 becomes extremely low octane, and can be dangerous in some engines. So dont just drain off the water when you see water in tanks, dump it all, and get new fuel!