Ethanol Killing Outboard Motors

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Are you a marine engine mechanic? Most of them I know have gotten gray hair dealing with ethanol problems. Some of your statements are not congruent entirely with facts. Ethanol has a known propensity and affinity to absorb moisture and as well there are phase separation issues. With an automobile or high use vehicle this problems are largely avoided but with boats (and my word if it were to be used in an aircraft) where they sit for weeks at a time or longer, ethanol is a KNOWN and FACTUAL problem.

I have had no particular issues with ethanol fuels since I am religious about keeping fresh fuel and pumping remaining fuel out and burning it off in my autos. I also dose with Starton and Techron (which is the major constituent of Mercury Quickleen product) or just run the Quickleen. The formula was changed a few years back and I, without any real evidence to back it up, believe that the older Quickleen is now provided as Quickcare (step 1) and Quickleen (step 2). If I know I have to leave fuel for a few weeks I dose with a marine fuel stabilizer. But, whenever possible, I purchase ethanol free fuel. It costs a small fortune to fill up as it is so if I have to pay extra to get a quality fuel, it is worth it.

There are plenty of ethanol threads on The Hull Truth boating forums with plenty of guys there who actually have experience in the marine boating industry and not just anecdotal here say.

N
 
AGAIN... I am a " MECHANIC "...... The biggest problems with ethanol is it's eating away at the rubber fuel lines in older engines.. Once it's gets in to the metering circuits of the fuel system it can be a nightmare.... The next problem is the older brass jets and floats... Open venting of fuel systems is not a very good thing ether..... And of coarse we need to tune to the power out put of the fuel being used...

So... We change out to newer fuel lines that are ethanol rated.... We use stainless steel jets and metering rods... Compost floats.... And use a charcoal filter and water vapor block on the venting system....

And if you run 100LL avgas... Remember it has 10 times the lead of normal leaded gas of the 70's.... I've seen plugs come out of aircraft engines were the plug was grounded across the electrode with lead...

If you wish... When I return to the states from Bonaire, I'll post photos of my shop and toys and then you can tell me if you think I may be a Mechanic...

Jim.....
 
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The biggest problem with boats is that cheaper boats have fiberglass tanks instead of aluminum tanks. Ethanol doesn't bother the aluminum tanks, but eats the resin in the fiberglass tanks. That resin plugs up all kinds of stuff in tiny fuel injector or carburetor passages.
 
I have had to replace 2 carbs on my lawnmowers due to this. I have a friend that has several racing quads. He has taking them all to his mechanic to get the white gunk out of the carbs due to ethanol. I currently buy gas with no ethanol for my lawnmowers and my boat.
 
Not that you should have too.. Thanks EPA Booooo...

But if you use Stabil, new gas lines, fuel water separator, and actually use your toys you will be fine.
 
If ethanol was the only problem.... It would be a problem in 100% of the engines..... This is not the case... It's a % of people that seem to have the problem and most don't... That tells my to look else where....

Jim...
 
AGAIN... I am a " MECHANIC "...... The biggest problems with ethanol is it's eating away at the rubber fuel lines in older engines.. Once it's gets in to the metering circuits of the fuel system it can be a nightmare.... The next problem is the older brass jets and floats... Open venting of fuel systems is not a very good thing ether..... And of coarse we need to tune to the power out put of the fuel being used...

So... We change out to newer fuel lines that are ethanol rated.... We use stainless steel jets and metering rods... Compost floats.... And use a charcoal filter and water vapor block on the venting system....

And if you run 100LL avgas... Remember it has 10 times the lead of normal leaded gas of the 70's.... I've seen plugs come out of aircraft engines were the plug was grounded across the electrode with lead...

If you wish... When I return to the states from Bonaire, I'll post photos of my shop and toys and then you can tell me if you think I may be a Mechanic...

Jim.....


Again, are you an experienced marine and outboard engine mechanic? What outboard and marine engines do you have experience and formal/factory training on? The anecdotal-isms aside.

I agree that with proper (fuel system) preparation, fastidious changes of filters, good additive selection and always using fresh fuel eliminates most of the (worse/serious) problems. But it still leaves a reduction in performance and fuel economy but I can live with that. Computer controlled engines seem to deal with ethanol fuels a little better that carburated engines, from a performance perspective, just an observation that may not be accurate entirely based on the three outboards I maintain in my family and the four I have owned since ethanol fuels became common.

I am also an experienced mechanic but I am not a professional marine engine mechanic, so the question remains when so many who are professional marine engine mechanics disagree with you. I enjoy your posts and respect your opinions and will continue to. Everybody has their knowledge areas but in this one case I think you are out of your depth here.
 
Factory trained.... NO... Thank god ... no...

tell you a little story about factory trained.... In 1982 I had a 4 cylinder cavalier that had a check engine light on.. So I stop at the dealer to get the codes read... They told me that it needed a O2 sensor and a new mass air sensor... OK... It's the dealer... They know what they are doing.. I tell them go ahead...

So they install the parts and reset the computer and charge me $275 bucks... I get 2 miles down the road and the light is back on... WTF... So I turn around and go back to the dealer... Now they call out the " HEAD " guy.... Now he tells me I need a new fuel flow sensor and the cat is most likely needing to be replaced...

I think for a minute and say.... Take off the " NEW mass air and O2 sensors and I'll be on my way... Give me my money back...

I get home to my shop and start poking around... Well well... There is a rubber heat spacer in between the intake and the throttle body.... I take my little smith gas torch and put a number 4 tip on it... Turn on the O2 and start moving it around the base of the throttle body with the engine running.. Sure as $hit it a plain old VACUUM LEAK ... Removed the throttle body and the rubber base has started to break down... Go to dealer and buy $20 rubber base gasket and re-install... reset computer... Light is off and never to re-light again... Car runs perfect....

So much for factory training.....:confused:

Jim
 
i agree that just being factory trained can leave a lot to be desired, but being a professional that works on these motors every day gives loads more experience.

I have seen far too many "part changers" that just blame the ethanol and throw parts at the problem until it is fixed.

With small engines the local shop will not rebuild a carb. if you have what sounds like a fuel problem they put on a new carb and tell you ethanol killed it.

I find that many shops will CYA and tell the people whatever they feel like as the general public does not know enough about mechanics to question....
 

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