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Results 1 to 18 of 18
  1. #1
    Join Date
    May 2007
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    Inverary, Ontario, Canada - The Great White North Eh!
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    Default Ethanol + Seafoam will kill your outboard!!

    I felt it was proper that I relate a recent problem I had. Since there is much debate about Ethanol in gasoline both good/bad. And while I have been a proponent of enhanced fuels maybe it's time I re-evaluated my opinion.

    I just returned from a fishing trip in Northern Ontario. I took my 14' boat fitted with my 1991, 15 horse Mercury/Mariner 2 stroke outboard up with me. The motor had never given me any trouble in the 14 years I have owned it and has never seen anything other than regularly scheduled maintenance (according to Merc guidelines), which I do myself.

    Since I have owned it (and like my two other small outboards) I run a TinyTach with hour meter. My very first issue occured just at the 2200 hour mark (don't know what the hours were on the motor which was 6+ years old when I got it - but safe to add a hundred or two for sure).

    The motor started fine and idled at the launch. It did a full throttle run for the 7 miles down the lake to the spot where we were setting up camp for the week. When I throttled down, it let out a helacious "sneeze", the rpms slowly dropped and she stalled dripping raw gas from the lower cowl. Removing the hood revealed all the signs and symptoms of a blown crank seal - no doubt about it, I have seen it before, just not on the little Merc's. That really sucks when you are 800 miles north of home and almost 200 miles (half of it dirt road) from the nearest Merc dealer.

    Anyhow, the week wasn't lost. As long as you gave it a touch of throttle it would run fine - but the gas mileage probably sucked running on about a cylinder and a half. On Sunday past I pulled the flywheel, removed the ignition and saw the seal - it was definately defective

    The seal puller plucked it out an it was quickly replaced with a new seal (20 bucks, can you believe it - seals for my Evinrudes go for under $5 - oh well). I put her all back together and it's running like it always has, nice and smooth once again.

    That got me thinking though, what could have caused it - hmmmm. I have been running ethanol in it since I got it. E-10 the first 11 years and E-15 for the past three. Maybe it was a cumulative effect....

    WARNING - After running ethanol enhanced gas at rates of 10% or greater for 14 years you will destroy the upper crank seals in 25 horse and under Merc 2 strokes.... OR

    Maybe it was the combination of E-15 and Seafoam. In the U.S. you guys/gals are well familiar with Seafoam. It only became widely available here in Canada in the past few months (now carried by Walmart Canada and Canadian tire). I had occassionally "smuggled" some accross the border but this is the first time I can clearly remember using it with my 15 horse.

    That must be the lethal combination. After all, the motor is 20 years old and until this mishap it had never had any repairs done to it - never pulled and cleaned the carb, much less a rebuild. No ignition troubles, leaky lower unit, chewed gears, never stalled, hiccup'd or burped before.

    So trust me when I say this (I now know from first hand experience) - NEVER mix Seafoam and Ethanol gas - even if your 20 year old motor has never had a problem ever in it's life, the lethal combination will EAT the upper crank seal right out of your powerhead

    I'm now starting to think about selling her and getting a nice new 4 stroke - they NEVER give you problems like this....

    (and if anyone is confused, the last statement really is sarcasm
    Graham

    A "professional" is someone who gets paid for their work - it doesn't necessarily mean they are good at it :)

  2. #2
    Join Date
    Dec 2009
    Location
    Rineyville, KY, U.S.A.
    Posts
    217

    Default Re: Ethanol + Seafoam will kill your outboard!!

    Thanks for the info, one of the senior techs at the local dealer was talking about the same thing a couple weeks ago when I was there.

  3. #3
    Join Date
    Sep 2003
    Location
    New Tripoli, PA, USA!
    Posts
    12,697

    Default Re: Ethanol + Seafoam will kill your outboard!!

    Four strokes have LOTS of their own problems!

    With that many hours on it, that little motor deserves some respect.

    Jeff

  4. #4
    Join Date
    Mar 2009
    Location
    Canberra Australia
    Posts
    109

    Default Re: Ethanol + Seafoam will kill your outboard!!

    2200hrs/14 years with no major work is a very good run for a small 2 stroke. I think it was just the seal's time to die. Although, you may have reduced the octane of the fuel with the Seafoam, and combined with the E15 leaning the fuel slightly (due to it requiring more ethanol per volume of air for complete combustion) may have leaned the mix too much. I would suggest going up one main jet size if you propose to run E15 regularly.
    I too am a huge proponent of alternate fuels and run my Volvo on E85, with no ill effects.

  5. #5
    Join Date
    Sep 2003
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    New Tripoli, PA, USA!
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    Default Re: Ethanol + Seafoam will kill your outboard!!

    Better you than me! Are you aware that ethanol requires 8 units of energy (produced mainly by coal burning) to produce only 10 units of energy? Are you aware that it can't be transported in pipelines like gasoline and has to be trucked all over the place (burning diesel and polluting the air)? Talk about a loser! The only reason we are stuck with gasahol is the evil collusion of misguided enviromental whackos, idiot politicians, and big agri-business.

    Jeff

  6. #6
    Join Date
    Oct 2007
    Location
    , ny, us
    Posts
    836

    Default Re: Ethanol + Seafoam will kill your outboard!!

    It will be interesting to see how long the new seal lasts. Can't help thinking that blow by past the rings might have ignited the charge in back of the piston and caused excessive crankcase pressure which might have blown the seal.

  7. #7
    Join Date
    Jun 2010
    Location
    Huntington Beach California
    Posts
    42

    Default Re: Ethanol + Seafoam will kill your outboard!!

    (ENVIROMENTAL WHACKOS) If this was a political web site I coulod understand your comments. Ethanol is not the answear I agree, however it was a step taken and as things evolve other green energy will work this out. I love the outdoors and want my grand kids to be able to enjoy it as well so enviromental whackos stand your ground.

  8. #8
    Join Date
    Mar 2009
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    Canberra Australia
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    109

    Default Re: Ethanol + Seafoam will kill your outboard!!

    Quote Originally Posted by fastjeff View Post
    Better you than me! Are you aware that ethanol requires 8 units of energy (produced mainly by coal burning) to produce only 10 units of energy? Are you aware that it can't be transported in pipelines like gasoline and has to be trucked all over the place (burning diesel and polluting the air)? Talk about a loser! The only reason we are stuck with gasahol is the evil collusion of misguided enviromental whackos, idiot politicians, and big agri-business.

    Jeff
    Pretty much all you have stated is dead wrong. Do yourself a favour and research ethanol, don't believe what you've been spoon fed by the mass media/friends.
    If the correct crops are grown for ethanol production, it is incredibly cheap to produce and those crops are very easy to grow, with a benefit of obtaining two totally separate products out of one crop, which reduces the prices even more.
    I'm not going to divert this topic any further, but you do owe it to yourself to get the facts. I did and that's why I run it.
    Last edited by typhoon; 06-30-2011 at 08:21 AM.

  9. #9
    Join Date
    Jun 2008
    Location
    Malden, MA,
    Posts
    283

    Default Re: Ethanol + Seafoam will kill your outboard!!

    [QUOTE=typhoon;341325]If the correct crops are grown for ethanol production, it is incredibly cheap to produce and those crops are very easy to grow, with a benefit of obtaining two totally separate products out of one crop, which reduces the prices even more.=QUOTE]

    But corn is not one of those products, and thats what its made from here.

  10. #10
    Join Date
    Mar 2009
    Location
    Canberra Australia
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    109

    Default Re: Ethanol + Seafoam will kill your outboard!!

    [QUOTE=emac;341341]
    Quote Originally Posted by typhoon View Post
    If the correct crops are grown for ethanol production, it is incredibly cheap to produce and those crops are very easy to grow, with a benefit of obtaining two totally separate products out of one crop, which reduces the prices even more.=QUOTE]

    But corn is not one of those products, and thats what its made from here.
    The reason it's made with corn over there is because your corn industry has been receiving massive subsidies for at least 20-30 years, ethanol production is just another subsidy in that respect.
    Like I said, do some research. Frankly, I'm tired of people who know absolutely NOTHING about ethanol as a fuel spouting off "information" and using irrelevant arguments about it. It makes them look ignorant and doesn't further the process of weening modern society off a heavy dependence on fossil fuels.
    No one mentions the massive costs of actually shipping crude to their countries for refining, nor the refining costs of that crude as an example. Nor all the pollution transporting that crude creates, all of which can be avoided by growing the crops more locally and refining closer to demand, instead of putting refineries at ports and then having to transport from there.
    Fact is, unless people take it up, the ethanol industry won't grow and push into more efficient production or crops. So support it, get off oil and enjoy the benefits of a 100-110 octane, clean burning fuel.
    But of course, whining about the price of fuel is better than actually doing something about it.

  11. #11
    Join Date
    May 2007
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    Inverary, Ontario, Canada - The Great White North Eh!
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    Default Re: Ethanol + Seafoam will kill your outboard!!

    Since I started this I should throw in my 2 cents here.

    As I originally stated I am a proponent of enhanced fuel and have been burning E-15 for the past three seasons in my outboards, my car, pick-up truck (which "drinks" gas) as well as the lawnmower, snowthrower, chainsaw and weed-eater.

    And while I don't understand all the science what I have read is 1) ethanol burns cleaner - and I believe that 2) ethanol is a little less efficient than regular gasoline - in the order of between 2-5% but as Typhoon notes, one of the benefits is that it (naturally) increases the octane of gasoline - which is why the E-15 I burn is 89 Octane as opposed to the "regular" 87 which "may contain up to 10% ethanol".

    However, as of yet, most "North American" engine designs do not take advantage of the ethanol enhancement to the fuel (save the few "flex fuel" vehicles out there). Ethanol will allow an engine to be designed with higher compression which will recover the lost efficiency - but as of yet there is no great push to force the mfg's to make the change.

    You need look no further than South America (can't recall off the top of my head - either Brasil or Argentina) that, as of this year, only sells E-85 at the pumps. After the oil embargo they decided to develop a plan that cut the middle east out of the picture.

    So either they use some magic on their engines or ethanol is not the boogey man we have been led to believe it is (hmmmm maybe it was Exxon or one of the others that started that rumour).

    Indy cars burn 100% ethanol, so perfomance engines can be built that outperform anything running on gas today with today's technology.

    Especially in the U.S. where you have the big, bad EPA contantly trying to "clean things up" I can't believe they haven't pressured the mfgs into producing outboards and other small engines that run on propane (LPG) or liquified natural gas (LNG). It's pretty difficult to spill one of them overboard and the technology already powers taxicabs and numerous city busses accross North America (and both fuels sell for significantly less than gasoline - enhanced or otherwise).

    Now, rethinking my blown seal once again - I guess it wasn't ethanol + seafom - it was really a Mid-Eastern plot supported by North American oil giants that keep my outboard using gasoline, which as of today is selling for $5.03 a gallon (Canadian) and since my dollar is now above the US dollar, is the equivalent of about $5.13/gallon $USD (and you think you have something to complain about south of my border?) instead of $2.60/gal for automotive propane or a whopping $1.59/gal for LNG (which is marked way up to include the "road tax"). If I could fill a natgas cylinder from home it would come in at about 60 cents a gallon.

    So am I for enhanced fuel - heck ya - anything that has the potential to break oil's monopoly and reduce my energy costs so that I can spend more time on the water for less money - that's a good thing...
    Graham

    A "professional" is someone who gets paid for their work - it doesn't necessarily mean they are good at it :)

  12. #12
    Join Date
    Jun 2010
    Location
    Huntington Beach California
    Posts
    42

    Default Re: Ethanol + Seafoam will kill your outboard!!

    Graham you sir are a gentalman and a scholar. I have to explaine my post as well. I did not disagree with one thing that you said, you are far more knowlegable than me when it comes to outboards and fuel additives (there is no contest) My complaint primaraly was that this is a outboard post not a forum for political ideals and I took afront to the enviromental whackos comment. I am concerned about our enviroment and took affence. I repeat I do not think ethonal is the way out of our oil problems however I do believe that it was a step taken (probably wrong) towards advancing need to cut oil usage and giving our $$ to middle eastern countries who do not have our intersest at heart.

  13. #13
    Join Date
    May 2007
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    Inverary, Ontario, Canada - The Great White North Eh!
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    Default Re: Ethanol + Seafoam will kill your outboard!!

    I agree and never intended this post to become a political platform.

    In a somewhat sarcastic way I was merely trying to point out that the best way to keep the "boogy-man" away from your outboard is take reasonable care of it and follow the mfg's maint schedule - it's really "just that easy".

    My seal died due to old age brought on by the fact that it survived more than 450 million (yes million) revolutions of the crankshaft before it said "ok, enough - I quit" (that's assuming an average of 3500 rpms during the over 2000 hours use I got out of it). In that time it did it's job while being subjected to the elements, temperature swings, old gas, new gas, dirty gas, additives, treatments, powertune, fogging oil, a bit of water now and then, ethanol and other assorted cooties that make their way into the fuel system.

    Did they contibute - surely - did they kill it prematurely? maybe. But if they did it certainly could be considered a slow death and not something the "average boater" need worry about.

    If you are concerned about keeping your outboard alive DON'T WORRY about ethanol, additives, oil pumps or any of the other "phantoms" that those experts (you know the guys - the ones with a PHD in dockside mechanical engineering) would have you believe will shorten your motors life.

    The bottom line is - I experienced my first mechanical problem with this motor at age 20, with an average use exceeding 100 hours per year. I achieved this "miracle" by doing nothing more than following it's service schedule - no magic there.

    But maybe this does support the phrase "they don't build things like they used to" because my 1986 model (9.9 Merc) and my two 1987 models (9.9 Merc and 2.5 Ev) have never had a mechanical issue - maybe 1990 was the "cut off" for quality parts
    Graham

    A "professional" is someone who gets paid for their work - it doesn't necessarily mean they are good at it :)

  14. #14
    Join Date
    Jul 2008
    Location
    , WV, USA
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    196

    Default Re: Ethanol + Seafoam will kill your outboard!!

    Quote Originally Posted by galamb View Post
    I agree and never intended this post to become a political platform.

    In a somewhat sarcastic way I was merely trying to point out that the best way to keep the "boogy-man" away from your outboard is take reasonable care of it and follow the mfg's maint schedule - it's really "just that easy".

    My seal died due to old age brought on by the fact that it survived more than 450 million (yes million) revolutions of the crankshaft before it said "ok, enough - I quit" (that's assuming an average of 3500 rpms during the over 2000 hours use I got out of it). In that time it did it's job while being subjected to the elements, temperature swings, old gas, new gas, dirty gas, additives, treatments, powertune, fogging oil, a bit of water now and then, ethanol and other assorted cooties that make their way into the fuel system.

    Did they contibute - surely - did they kill it prematurely? maybe. But if they did it certainly could be considered a slow death and not something the "average boater" need worry about.

    If you are concerned about keeping your outboard alive DON'T WORRY about ethanol, additives, oil pumps or any of the other "phantoms" that those experts (you know the guys - the ones with a PHD in dockside mechanical engineering) would have you believe will shorten your motors life.

    The bottom line is - I experienced my first mechanical problem with this motor at age 20, with an average use exceeding 100 hours per year. I achieved this "miracle" by doing nothing more than following it's service schedule - no magic there.

    But maybe this does support the phrase "they don't build things like they used to" because my 1986 model (9.9 Merc) and my two 1987 models (9.9 Merc and 2.5 Ev) have never had a mechanical issue - maybe 1990 was the "cut off" for quality parts
    So you pretty much contradicted the entire reason you posted in the first place.

  15. #15

    Default Re: Ethanol + Seafoam will kill your outboard!!

    A Mercury Certified mechanic who wasnt a fan of ethanol recommended that I always use Marine type STABIL.Doing that in new Mercury 9.9hp 4stroke motor. He showed me a carb from his workbench and it had quite a bit of a whitish scale like deposit throughout. Was told that was a result of using todays gas whithout an addititive like STABIL. When I started this thread I stated I was relatively new to the outboard market and have learned a lot from your responses. Now wondering if those whitish scale like deosits were from Ethanol or something else? Thanks.

  16. #16

    Default Re: Ethanol + Seafoam will kill your outboard!!

    I meant the Ethanol Problems thread. Sorry.

  17. #17
    Join Date
    May 2007
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    Inverary, Ontario, Canada - The Great White North Eh!
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    Default Re: Ethanol + Seafoam will kill your outboard!!

    I didn't contradict anything. The purpose of my post was not to discuss the "political" views, ramifications, rhetoric surrounding enhanced fuels but simply to point out that whether or not you agree with their use, whether or not you think they help with polution etc etc, the fact is I have been running ethanol fuels in my outboards for many many years now and have personally found no ill "mechanical" effects from their use.

    That was my whole point - politics aside, I can find nothing to support the various claims (sometimes by "so-called" experts in the field) that ethanol will cause harm to an outboard.

    The arguements about more carbon, less carbon, gas in the lakes etc would have less meaning to you if the only fuel available killed your motors at 5 year intervals. My point was, after 14 years and 2200 hours of run time, burning ethanol gas the whole time, I finally observed my first mechanical issue with the motor.

    Based on many motors that I see that are 10 plus years old and have barely 200 hours on them at that rate, if ethanol was the cause of my mechanical issue, the "average" outboard would be over 100 years old before it went through as much ethanol enhanced fuel as my motor already has. And if it takes that long to suffer some ill effects, then maybe the fuel isn't the problem.

    Be honest for a moment here. If you go into a dealer and he tells you it's going to be 500 bucks to fix your motor would your rather hear 1) "what can I say - it's that killer ethanol, nothing you can do about it" or 2) "no wonder it's running like crap - it doesn't look like you have taken care of it at all - do you think these things service themself"

    And while the second statement is closer to the truth, the first statement will keep you as a customer....
    Graham

    A "professional" is someone who gets paid for their work - it doesn't necessarily mean they are good at it :)

  18. #18
    Join Date
    May 2007
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    Ireland,the only country in the world you can go North to go South
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    Default Re: Ethanol + Seafoam will kill your outboard!!

    I don't know a lot about ethanol,user name.Or the political jargon,but in my HOP,being a conpiriscy theroist, someone is making money,and it ain't your ordinary 5/8th on the street,and it has sweet bu$%er all to do with green,eco,or anything else but expanding the thickness of someone's wallet,and I'm not talking about mine.

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