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Ethanol Problems

T

tigerjohn

Member
I am relatively new to the outboard motor market and am interested in YOUR opinions on gasoline that contains ethanol. Been hearing that it's in all brands to varying degrees. I've been told and actually shown what it can do to a carb. Also been told to always use Stabil or an equivelant. I am running a new 9.9hp Mercury 4 stroke and would like to avoid future problems. Thanks.
 
Stay away from ethanol whenever you can. Use Stabil or equal designed for ethanol if you have to use fuel containing it.
 
Do all brands of gas have ethanol in them? Been using MOBIL 87 octane. Also should I run the engine till dry after use? All tips welcome. Thanks.
 
Ethanol problems are highly over exaggerated. It does not cause all the problems that some believe. My area of the world has been on it for over 12 years now and I know no one that has had a confirmed ethanol problem. I have about 12 various motors around the house and have had no problems. I do use Sea Foam in all of them for what its worth.
 
I live in SW Ohio where ethanol use is limited. The only problems w/ethanol that I am aware of are occurring w/boats that have fiberglass fuel tanks and some boat engines are experiencing swollen soft fuel lines with extended use of it. If you have to use it w/a 9.9 hp it probably won't hurt it but I believe it is not recommended by Merc. I would only run it through my engine in small quantities over a short period of time since it is hydroscopic. Definitely don't store it over the winter and never run E85 in an outboard engine except in an emergency. I only run the carbs dry when I put the boat away for the season since I use it several times per month and always use a fuel stabilizer. JMHOs
 
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I'm not sure about what's recommended for newer engines, but I run all old stuff. I find that ethanol fuels are causing troubles with the older rubber compounds, such as gaskets and fuel lines. I try and avoid using fuel with ethanol in it, for that reason. The only fuel here (Canada) that I know of that doesn't have ethanol in it is Shell Premium. Regular is up to 10% and mid-grade is up to 5% ethanol. So, I pay the extra for premium. I've also got an old sled (72) and regular gas was giving me nothing but trouble, so it gets premium now and runs better. Everything from my outboards to my lawnmower gets Seafoam in it.
 
I run ethanol blend in everything including vintage stuff. if you make sure your fuel system is clean and use ethanol resistant lines you should have no problems using it. As stated some people over exaggerate on the problems but lots of people even store it over the winter/summer and never have any problems with it, just stabilize it right when it's bought, not a week or so later. Also running premium in a motor not designed for it is not the best either as you'll lose power because the fuel won't keep up with the motor.
 
Fuel requirements - Any automotive gasoline or a gasoline with no more than 10% ethanol with a minimum octane of 86 (90 RON).

The above is contained in my 1986 OMC service manual. 25 years ago the mfg's were already building motors and parts that were "ethanol safe".

Ethanol is not the boogey man that it's made out to be.

I'm now in my third season of running 89 Octane E-15 (15% ethanol) in my four outboards. They range in horsepower from 2.5 to 140, all are 2 strokes and the "newest" one is a 1991 model. The E-15 is being selectively tested in my area and they sell it for the same price as the regular 87 octane.

I decided to give it a try since 1) it's coming soon to a pump near you whether you live in the US or Canada 2) I had been running E-5 or E-10 for years with no ill effects.

On the down side - ethanol produces a little less power than regular gas. I have compensated by running the couple extra octane.

Ethanol is also far more prone to "phase separation". It absorbs moisture which separates out and sits as water in the bottom of the tank. Not a problem in your car since you burn the gas relatively quickly. Can be an issue in a boat which may only see one tank of gas a season.

So, you can stablize the gas with Stabil (or any of the generic brands), Seafoam (which also cleans "cooties" from the system) or one of those wickedly high priced products that claim to have "enzymes" that save you from the evils of ethanol, or,

you can run fresh gas all the time (less than 2 weeks old) - easy to do if you use a portable tank.

On the upside, ethanol burns cleaner and keeps you fuel system cleaner than regular gas. The stuff that OEM dealers sell to clean your intake/carb/injectors is almost chemically identical to ethanol (hmmm, use a product like ethanol to clean your carb/injectors, but it's otherwise the death of your motor if you add it to gas - non-sense)

If this board existed about 35 years ago the discussion would have been similar about the switch from leaded to un-leaded gas. I guess unleaded wasn't the "killer" it was made out to be back then.

I have left out the #1 reason why you should ALWAYS use E-10 fuel. If you neglect your motor and never do any maintenance the day will come along when you will be at the dock, in front of a crowd no less, and the motor won't start. At that point you can say very loudly "that damn ethanol". Numerous guys will nod their heads knowingly and may even comfort you with a shoulder pat and you will absolved from any responsibility :)

Use the ethanol, keep it stablized or fresh. It won't eat your carb, or fuel lines, or cause an overheat, or force you to hit rocks or any of the thousand other plagues that get tossed around...
 
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I agree with Graham. I see far, far too many old age/poor maintenance of fuel system issues blamed on ethanol. What I find bizarre is people will claim ethanol in fuel is the Adolf Hitler of fuel additives, but will happily put water removing treatments (ethanol) into their fuel systems.
Phase separation is an issue, but a good pre engine bowl separating filter eliminates this issue, as does ensuring tanks are stored either full or completely empty and vents sealed. If you run your carbs dry or drain them after use and check filters (normal proper maintenence), you'll never notice any ethanol related issues.
So, go ahead and replace those 20 year old fuel lines and pump diaphragms (the ones that are about to fail anyway) with newer, alcohol rated parts and forget about the problems.
As an aside, I've been running E85 in my Volvo for six months now and I'm still waiting for the onset of all the destructive ethanol problems to hit....
 
Summary from Mercury Endurance Study - Effects of E15 Ethanol on engines...pg.50

Thought this might be of interest to you here:
Mercury (NREL) released report in November 2011 on effects of E15 gasoline - The study ended early due to engine failure.

Copy of Report summary below:
(Note: Highlighting, colors bold and other formatting is on my own personal copy, not in original report released).

Most ethanol-caused engine problems arepreventable (or manageable) when gas is of high quality, below legal limit of10% and all "necessary precautions" are followed...
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"High EthanolFuel Endurance - Summary of Results: ​

A Study of theEffects of Running Gasoline with 15% Ethanol Concentration in Current Production Outboard Four-Stroke Engines
and Conventional Two-Stroke OutboardMarine Engines"

Report by David Hilbert Mercury Marine Fond du Lac, Wisconsin, October 2011
NREL is a national laboratory of the U.S.Department of Energy, Office of Energy Efficiency & Renewable Energy,operated by the Alliance for Sustainable Energy, LLC.
Copied from nrel.gov docs on11/27/2011. Current link to report (as of 12/14/2011) http://www.nrel.gov/docs/fy12osti/52909.pdf
----------------------------------------------------------------------------------------------------------------------
Pg. 50 of 52:
Final Summary:
EPA’s recent announcement of a partial waiver approving E15 fuel for use in 2001 and newer cars and light trucks will create an opportunity for consumers to misfuel their marine engines. This program indicates that misfueling currently available marine outboard engines may cause a variety of issues for outboard engine owners.These issues include driveability, materials compatibility, increased emissions, and long-term durability. There were also 2 examples of how the ethanol fuel caused an increase in fuel consumption.

9.9HP Carbureted Four-Stroke:
The E15 engine showed high variability in HC emissions at idle during the emissions tests at the end oft he 300 hour endurance period. Both the E0 control engine and E15 test engine ran leaner at idle and low speed at the end of the endurance test. When operated on E15 fuel after 300 hours of endurance, the lean operation at idle coupled with the additional enleanment from the E15 fuel caused the engine to exhibit misfire and poor run quality (intermittent misfire or partial combustion events). A misfiring engine would causecustomer dissatisfaction due to the inabilityto idle the engine properly, excessive shaking, and hesitation or possiblystalling upon acceleration. As it relates to this study, the misfire caused an increase in HC emissions at idle. This increase in HC variability at idle caused the average total HC + NOx to increase from the start to end of endurance, whereas the HC+ NOx on E0 fuel on both engines showed a decreasing trend. As expected, the CO emissions were reduced when using E15 fuel due tot he leaner operation.
The power and torque output of the E15 engine was higher with E15 fuel than with E0 fuel. The power and torqueo utput of the E0 control engine increased slightly with more endurance time. The power and torque output of the E15 test engine showed a flat or declining trend with more endurance time.
The end of test inspection showed evidence of elevated temperatures on base engine components due to the lean running on E15 fuel. There were significantly more carbon deposits on several components of the E15 engine, indicating that these parts likely had higher metal temperatures during operation. Hardness measurements indicated that the pistons had higher operating temperatures on the E15 engine. The exhaust gas temperature increased 17°C at wide open throttle as a result of the leaner operation on E15 fuel.
The fuel pump gasket on the E15 engine also showed signs of deterioration compared with the E0 engine after approximately 2 months of exposure to E15fuel.

300HP Four-Stroke Supercharged Verado:
The E15 Verado failed 3 exhaust valves prior to completionof the endurance test. One valve completely failed and 2 others had developed significant cracks. Metallurgical analysis showed that the valves developed high cycle fatigue cracks due to excessive metal temperatures. The majority of exhaust valves on the E15 engine lost a significant amount of lash which may have contributed to the observed valve failures. The exhaust gas temperature increased 25-30°C at wide open throttle due to the lean operation with E15 fuel.
In addition to the elevated temperatures on the exhaust valves, the pistons showed evidence of higher operating temperatures. The carbon deposit differences indicated that the E15 engine’s pistons were hotter during operation. (Note: This Mercury report summary was posted on November 27th, 2011 and thereafter by Gail at Fuel-TestersCompany, on their websites fuel test kit dot com and www. fuel-testers .com.+forum message board: fueltesters. website toolbox .com -If you find this exactr eport on any other website, not posted by us, that includes this note without giving full credit to Fuel-Testers for supplying the report information, the site you are at is guilty of plagiarism and/or copyright infringement - FuelTesters company invests a tremendous amount of time and expense educating the public on ethanol; At the very least, when someone copies they should give fullc redit to the original source. Please notify us of this, email fuel testers atyahoo dot com. Thank you. Report continues here). The E15 Verado generated HC +NOx values in excess of the Family Emissions Limit when operated on E15 fuel, but did not exceed the limit when operated on EEE-E0. The primary contributorto the increase in exhaust emissions was the NOx due to enleanment caused bythe oxygenated fuel. The CO emissions were reduced when using E15 fuel due tothe leaner operation, as expected.
At emissions mode point 3, the lean combustion due to the E15 fuel caused the engine to lose torque output due to operation significantly leaner than LBT. As a result of the torque loss, the throttle input had to be increased 10% to maintain the same torque output as on E0-EEE fuel. The change in throttle input caused an increase in fuel flow of 10%. Mode 3 is representative of a typical cruising speed and load. The E15fuel would cause the fuel consumption to be 10% higher at that operating point for a customer.

- End of pg. 50 Pg 51 will be continued in next post...-----------------------------------------------------------------
The entire report can be viewed at NREL.gov website;
or to request a copy of the complete report (54 pages) in PDF format from us- Contact Fuel-Testers Company here: http://www.fueltestkit.com/questions_contact_fueltesters.html
 
Continued...Merc Marine Ethanol E15 Endurance Study: Pg. 51 of 52

Continued...Pg. 51 of 52: (Pg. 50 -Summary see my prior post) due to limitation of 10,000 characters per post...
From Mercury Marine E15 Endurance Study: Summary Pages (51+52)

200HP EFI 2.5L Two-Stroke: ​

The 200HP EFI two-stroke engine showed no signs of exhaust emissions deterioration, though the emissions output after the full endurance testing was not measured due to a failure of the E15 engine. The primary driver of theHC + NOx emissions on this engine family was HC (approximately 98% of the HC + NOx total). As expected, since the E15 fuel caused the engine to run lean, the HC emissions were lower, as were the CO emissions. There was more variability of HC + NOx observed on the E0 engine than the change in emissions on the E15 engine.The deterioration of the CO emissions had similar trends between the 2 engines.
The endurance test of the E15engine was stopped short of the 300 hour target due to a connecting rod bearing failure on cylinder 3.The root cause of the bearing failure could not be identified. More testing is necessary to understand the effects of ethanol on two-stroke engine lubrication mechanisms where the oil and fuel move together through the crankcase. The E0 engine completed the entire 300 hours ofdurability testing.
Other than the bearing failure, the end of test teardown and inspection did not show any visible significant difference between the 2 engines. Hardness checks performed on the pistons of both engines indicate that the E15 engine may have had higher piston temperatures, a concern on two-stroke engines where higher temperatures could lead to more power cylinder failures. The exhaust gas temperature increased15-20°C on average due to the lean operation with E15 fuel.

4.3L V6 EFI Four-Stroke CatalyzedSterndrive
Since E15 fuel was readily available in the test facility and an engine equipped with exhaust catalysts was on the dynamometer, emissions tests were conducted on a 4.3L V6 sterndrive engine. No durability testing was performed. At rated speed and wide open throttle the exhaust gas temperatures increased by 20°C on average and the catalyst temperatures increased by 30°C. This increase in catalyst temperature would likely cause more rapid aging and deterioration of the catalyst system at WOT. The overall effect of the increase in deterioration rate would be duty cycle dependent. The HC and CO values decreased at the Mode 1 (rated speed,rated power) emissions test point, which is an open loop operating point, dueto leaner operation with E15 fuel, as expected. The fuel consumption increasedby 4.5% at the operating points that were running in closed-loop fuel control.

Recommendations:
This test program was limited in scope in terms of operating conditions. More investigation is necessary to understand the effects over a broader range of conditions. Ethanol’s effects on part load operation, cold start, hot restart/vapor lock, and overall driveability need to be evaluated. The wide range of technology available for marine engines due to the wide range of engine size will complicate this issue significantly. Mercury Marine produces engines from 2.5HP-1350HP with a wide array of technologies ranging from two-stroke or four-stroke; carbureted, EFI, ordirect fuel injected; naturally aspirated, supercharged, or turbocharged; and more.
Ethanol’s ability to absorb water into the fuel is of paramount concern for the marine market and this issue has not been addressed in this test program.
The contaminants that water can bring with it, potentially saltwater, can cause severe corrosion in fuel systems. A leak or fuel system failure could cause the engine to be inoperable and leave the vessel stranded, which would obviously be a major dissatisfaction to the customer.
In addition, a better understanding of the effects higher ethanol blends have on marine fuel systems in terms of materials compatibility and corrosion is needed. Marine vessels tend to have very long storage durations, can be stored in very humid environments, and will have more opportunities to have fuel system exposure to water, including saltwater.
More testing is needed tounderstand how ethanol blends affect oil dispersion in two-stroke engines thathave fuel and oil moving through the crankcase together. Ethanol tends to be a good solvent and may break down lubrication at critical interfaces by cleansingt hese surfaces of the residual oil film.

End of pg. 51 - See above post for pg. 50 and more report details.

Current link to full original report (as of 12/14/2011) http://www.nrel.gov/docs/fy12osti/52909.pdf
(Report summary here, provided by Fuel-Testers Company) - Font formatting (bold and highlights for emphasis) not from original report copy.
 
bill_w said:
I'm not sure about what's recommended for newer engines, but I run all old stuff. I find that ethanol fuels are causing troubles with the older rubber compounds, such as gaskets and fuel lines. I try and avoid using fuel with ethanol in it, for that reason. The only fuel here (Canada) that I know of that doesn't have ethanol in it is Shell Premium. Regular is up to 10% and mid-grade is up to 5% ethanol. So, I pay the extra for premium. I've also got an old sled (72) and regular gas was giving me nothing but trouble, so it gets premium now and runs better. Everything from my outboards to my lawnmower gets Seafoam in it.
Click to expand...

IMO Seafoam is one of the worst brand of additive products you could use in ethanol-blends of fuel - For most, Seafoam will just increase your risks for problems, cause gumming...
Always check the ingredients of additive before using with E10 - Ethanol is a solvent, cleanser, drying agent, water absorber, antifreeze, etc. - You don't want to add more of these types of ingredients if you already have 5-10% ethanol alcohol in gasoline.
As for Seafoam in non-ethanol gasoline, I have no opinion- It's your money spend or waste it as you see fit.

Personally and professionally my overall impression of probably more than 90% of additives sold, are a complete waste of money. (There are 7000+ gas additives registered with the EPA)-
Another tip/hint - If the gas additive company advertises that their product "will solve all you ethanol problems" they are lying-

Gas quality (not additives) is the most important precaution to avoid unnecessary ethanol problems-


Gasoline usually contains hundreds of ingredients (varies based on brand, location and other factors) -
Ask yourself, if there really was a miracle, inexpensive, liquid chemical that is so beneficial at preventing, fixing, or correcting ethanol problems, why isn't the gas company already putting it into the gasoline????

(BTW, gas stations have the same problems you have with tank and equipment, just on a bigger scale (20,000 gallon tanks and very expensive equipment) - Plus, gas retailers have no incentive whatsoever to sell you bad or unstable gasoline - If an ingredient works - (E.G. stabilizers) it's already in the gas; And Shell or one of the other big chemical suppliers/ oil companies probably also has the patent for that ingredient -
E.G. "Shellsol" (registered trademark) is found in many gas additives - If you like this ingredient so much, would be much cheaper to just buy Shell gasoline.
IMO Shell gas with ethanol is a brand I would be least likely to buy - Shell brand WithOUT ethanol it's fine - Shell is an excellent company, but... -I'll add more later, if you want/need details...
 
IMO Seafoam is one of the worst brand of additive products you could use in ethanol-blends of fuel - For most, Seafoam will just increase your risks for problems, cause gumming...
Click to expand...
Is your opinion based upon test data or a WAG? I don't use E-10 or E-15 fuels in my engines. I am a believer in Seafoam reducing fuel varnish/gum deposits in my engines that get stored over the winter. Haven't had a fuel related problem since I began using it years ago.

I agree about using pure Shell gasoline. I also use Exxon, Mobil, Sunoco and will use BP if the aforementioned fuels are not available. Thanks for the test data; very interesting.
 
guyjg said:
Is your opinion based upon test data or a WAG? I don't use E-10 or E-15 fuels in my engines. I am a believer in Seafoam reducing fuel varnish/gum deposits in my engines that get stored over the winter. Haven't had a fuel related problem since I began using it years ago.

I agree about using pure Shell gasoline. I also use Exxon, Mobil, Sunoco and will use BP if the aforementioned fuels are not available. Thanks for the test data; very interesting.
Click to expand...
Your welcome - What does "WAG" stand for?
All alcohols, being very strong solvents, cleansers and degreasers, will clean and "reduce varnish/gum deposits".
With E10 readily available, you don't need to buy a gas additive to accomplish that anymore. 10% ethanol is more than enough to keep engine clean.
(Actually 1% is plenty, 10% is too much).

Their recent 2011 study/report, backs up another large study on Mercury engines and ethanol back in 2003, called "Marine Outboard Driveability Assessment to Determine Impacts of a 10% and 20% Ethanol Gasoline Fuel Blend" completed by Orbital Engine Company.

My opinion on Seafoam is based on the product's ingredients and numerous reports I have received from our customers and visitors (Fuel-Testers), over the past 5-6 years, that had problems with E10 due to Seafoam - (Of course I have no way to validate their reports - but they all seem to have the same type of problem -gumming, clogging of carb, milky substance, etc.
Seafoam "Motor Treatment" product contains 10-20% IPA (isopropyl alcohol, CAS# 67-63-0) + petroleum distillates (naphtha).

They (Sea Foam Sales Company, MN) may have other products now?- If they do I would still check MSDS before using them - (Actually I would never recommend using them) - Like many additive companies I find their website and literature very deceptive and/or misleading.

EG. Their product(s) contain alcohol, but on their website they deceptively state,
"...Sea Foam® continues to manufacture its additives using the same 100% pure petroleum formula developed by the company’s founder, Fred Fandrei back in the 1930’s...." - http://www.seafoamsales.com/
Product is NOT 100% pure petroleum.
Note: Many additive companies are deceptive - But the ones that blatantly lie, I could never trust or consider using/testing their products.

If you believe you MUST use an additive with E10 gas (usually you really don't need them unless you have a specific problem),
always best to use products that do not contain alcohols or strong solvents.
Examples: Maxima fuel storage stabilizer is probably my personal favorite in the "retail" additive category (racing industry company), plus many use Stabil and Startron, and there are many others that are much safer than Seafoam with E10 gas type.

Hope this information is helpful - Anything I write here is my opinion (unless I quote or copy a report or something like I did above),
My E10 info is based on many years being directly involved in ethanol/gas industry/renewable energy (ethanol fuel testing) - and since I interact with all engine-type owners and all types of businesses (from government to engine manufacturers and others), from all over the world- I believe I have a very accurate assessment (and reliable opinion) on what's really going on with ethanol, both good and bad.

Additive Products is NOT the solution to E10- At best it's a "band-aid" - Protecting your right, to choose to buy ethanol-free gas for marine engines, is the most effective solution/remedy regarding E10.
 
"WAG" = Wild Arse Guess

Thanks for the info on Seafoam. I don't use ethanol fuels so I'll keep using it as needed for fuel system cleaning. My 115 Merc. gets a double shot of Stabil w/each tank fill up only because I don't know if I will be able to use up all of the fuel before it begins to varnish. I have MS and it rears its ugly head up whenever it feels like it just like last June-Sep. I could barely walk or maneuver and my muscles felt like I was a walking under a nest of stinging hornets. It subsided in Oct. in time to deer bowhunt. Thanks again.
 
I have a '95 model merc 25hp. Last year I added no "additives". Had problems. It wouldn't start after sitting for 1-3 weeks. The only way to get it to fire was to squirt fuel in the carb. I had some trips where I ran it dry and some where i left it full of fuel. This year I have been adding stabil's marine formula every time I fuel up. NO problems yet.
 
loosenut said:
I have a '95 model merc 25hp. Last year I added no "additives". Had problems. It wouldn't start after sitting for 1-3 weeks. The only way to get it to fire was to squirt fuel in the carb. I had some trips where I ran it dry and some where i left it full of fuel. This year I have been adding stabil's marine formula every time I fuel up. NO problems yet.
Click to expand...
Fresh, properly blended E10 gas (10% or les ethanol) would not cause those symptoms to your engine year/type.
So basically you're buying fuel to fix or perk-up bad fuel...It's STILL bad fuel, which is certain to negatively affect your engine over the long term.

DID YOU VISULAIZE GAS (HAZY, CLOUDY OR PHASE-SEPARATED) TO MAKE SURE GAS WAS NOT WATER-CONTAMINATED WHEN YOU BOUGHT IT?
DID YOU TEST THE PERCENT ALCOHOL OF GAS YOU PURCHASED?
(My educated guess is percent ethanol was far above 10% and/or higher ethanol caused rapid water absorption and decreased energy of fuel).

Distillates (KEROSENE petroleum), hydrotreated light (MINERAL SPIRITS) CAS# 64742-47-8 and 64742-53-6 (primary ingredient in Stabil)
aka Kerosene have higher BTU energy than ethanol-blends of gasoline which is why kerosene based-products "appear" to help - They might boost the energy of gas, but you're still using bad fuel.
 
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I'm at the mercy of the gas station for fuel quality. Over the years I've tried all the gas stations in town, same results. Years ago ONLY bought from the shell station. They did not sell anything with ethanol. They changed ownership and now do not sell any without ethanol.
Found a combination that worked for me, that is unfortunately how it will go. Just trying to cope.
Whether or not I visualize the gas doesn't much matter, the next closet gas station is 10 miles away. The wrong way. No I did not test the percent of alcohol. Not at all arguing the possibility of them being over the legal limit.
 
loosenut said:
I'm at the mercy of the gas station for fuel quality. Over the years I've tried all the gas stations in town, same results. Years ago ONLY bought from the shell station. They did not sell anything with ethanol. They changed ownership and now do not sell any without ethanol.
Found a combination that worked for me, that is unfortunately how it will go. Just trying to cope.
Whether or not I visualize the gas doesn't much matter, the next closet gas station is 10 miles away. The wrong way. No I did not test the percent of alcohol. Not at all arguing the possibility of them being over the legal limit.
Click to expand...
Pretty ridiculous isn't it - That we have the need to question the quality of gas now being sold??!! What other highly regulated government controlled and subsidized industry gets away with so much??? I agree you should not have to test, but those who have had engines unnecessarily damaged by excess ethanol find it is a simple solution.
Not sure where your are, but there are several areas that consistently sell gas with 15-20% ethanol - Maybe if the VEETC tax credit is not renewed this year there will be less of an incentive to overblend ethanol in gas...
BTW. although Shell without ethanol is fine, many find the lower energy of Shell gasoline creates performance problems due to lower energy of fuel - 10% ethanol is a cleanser (plenty) but Shell still adds many additional cleansers (they brag that it's 4 times the amount required by the EPA) - "Cleansers" have low BTU energy - the more cleansers (and unnecessary ingredients) you add, the lower energy of the fuel - spark-ignited engines need energy (high BTU) to perform.
I stopped buying Shell when they switched to E10 - I'm still hoping they redesign their formula to be more compatible with ethanol. Even if you don't experience performance issues from low energy, most find Shell brand with ethanol dramatically reduces MPG.
 
..."I have a '95 model merc 25hp. Last year I added no "additives". Had problems. It wouldn't start after sitting for 1-3 weeks. The only way to get it to fire was to squirt fuel in the carb. "

Your problem is a plugged enrichener circuit. Here's how to fix it (no tools required): Next time it's running and warmed up, rev it good in neutral and put the "choke" full on. The motor will load up and try to stall, so be ready to turn the choke off before it does, then rev it good again. That cleans out the circuit

Do this EVERY time you run the motor, just before shutting her off for the day, and all will be well.

Jeff
 
fuel-testers said:
Pretty ridiculous isn't it - That we have the need to question the quality of gas now being sold??!! What other highly regulated government controlled and subsidized industry gets away with so much??? I agree you should not have to test, but those who have had engines unnecessarily damaged by excess ethanol find it is a simple solution.
Not sure where your are, but there are several areas that consistently sell gas with 15-20% ethanol - Maybe if the VEETC tax credit is not renewed this year there will be less of an incentive to overblend ethanol in gas...
BTW. although Shell without ethanol is fine, many find the lower energy of Shell gasoline creates performance problems due to lower energy of fuel - 10% ethanol is a cleanser (plenty) but Shell still adds many additional cleansers (they brag that it's 4 times the amount required by the EPA) - "Cleansers" have low BTU energy - the more cleansers (and unnecessary ingredients) you add, the lower energy of the fuel - spark-ignited engines need energy (high BTU) to perform.
I stopped buying Shell when they switched to E10 - I'm still hoping they redesign their formula to be more compatible with ethanol. Even if you don't experience performance issues from low energy, most find Shell brand with ethanol dramatically reduces MPG.
Click to expand...

Right on! If you want something SCREWED UP just let the goverment in on it, and sure as h**l it will be done as well $$$ more.

Oldman570
 
Spot on!

On that report (above) on Mercs leaning out and running higher temps.... Using 10 to 15 % ethanol gas REQUIRES a re-jetting (richer) to compensate for the fact that more fuel is required than for running on pure gas. I'd love to see what the results would have been with companion engines that were re-jetted. I'll bet it would have run fine, though they gas mileage would have been poorer.

Jeff
 
fastjeff said:
Spot on!

On that report (above) on Mercs leaning out and running higher temps.... Using 10 to 15 % ethanol gas REQUIRES a re-jetting (richer) to compensate for the fact that more fuel is required than for running on pure gas. I'd love to see what the results would have been with companion engines that were re-jetted. I'll bet it would have run fine, though they gas mileage would have been poorer.

Jeff
Click to expand...
I believe any engine can be modified to run very well on higher blends of ethanol - even E85 and E100 - It's be done over the years with many engine types, especially in the racing industry...
The problem is simple science:
Ethanol alcohol attracts and absorbs water - Oil and water don't mix...
Gas separates and becomes contaminated...

Now, if you removed or replaced the ethanol-gas from your tank and fuel system almost everyday, like the racers do, you should NOT have a problem -

But, for the majority of boat engine owners, you'll never be able to remove the risks posed by a water environment and reality that boaters (and other specialty or recreational engine types) store fuel for prolonged periods of time.

There is no scientific or simple solution to stop alcohol from attracting and absorbing water -
(although several gas additive companies try hard to deceive and convince you there is some miracle ingredient that stops water absorption in gas with ethanol)- No chemical ingredient exists.
That's what all alcohols are expected to do - ATTRACT/ABSORB WATER -
Isopropyl, methanol, ethanol, etc. all alcohols are hygroscopic by nature, just like they all are very strong solvents, cleansers, degreasers, etc. -
That's where the main problems lie with E10, E15 and higher ethanol-blends of gas.
With ethanol, performance issues can easily be corrected, water issues and parts damage or deterioration can not.
 
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hree Ethanol Myths Clarified
By Bob Adriance( Editor of Seaworthy, the BoatUS Marine Insurance damage-avoidance publication)

It's time we get to the bottom of how E10 is affecting our engines

In the few years since ethanol began to be widely used in the United States, a lot has been written about its properties, the problems it's created, and how to best cope with its possible effects. Some of the advice has been based on science, some on hearsay. While E10 is not an ideal fuel – and E15 could cause serious problems for marine engines – at least a few myths about ethanol have arisen with the potential to do more harm than good:
Myth #1: Ethanol-enhanced gasoline (E10) loses octane much faster than regular gasoline.

Many mechanics believe that octane loss during winter storage could be great enough to damage an engine when it's run in the spring. These same mechanics will often recommend leaving the tank almost empty so that fresh gasoline can be added in the spring to raise depleted octane levels. While all gasoline loses octane as it ages, ethanol-enhanced gasoline loses octane at about the same rate as regular gasoline, according to Jim Simnick, a technical advisor at BP Global Fuels Technology, and Lew Gibbs, a senior engineering consultant and Chevron Fellow. The two men have over 75 years of combined experience working with gasoline and both agree that the loss of octane over the winter would not be sufficient to damage an engine. Note, however, to keep any gasoline, including E10, as fresh as possible; they said it's good practice to always add fuel stabilizer — an antioxidant — whenever the boat will be idle for long periods.

The recommendation to leave a tank mostly empty is bad advice; it could significantly increase the amount of water that gets into the tank. When enough water enters through the vent, the ethanol will separate ("phase separate") from the gasoline. Leaving a tank mostly empty does three things to increase the chances of phase separation:

It increases the volume of open space in the tank (its "lung capacity") so it can "breathe in" damaging moist air. An almost-empty tank leaves more space on tank walls for condensation to form. Leaving less gasoline in the tank means there will be less ethanol to absorb the condensation.

It's interesting to note that in areas of the Midwest that have been dealing with E10 for over a decade, topping off tanks is common practice. (As an alternative, completely emptying the tank would eliminate any chance of phase separation.)

If phase separation occurs, the highly corrosive ethanol/water mixture will settle to the bottom of the tank and remain there even after fresh fuel is added in the spring. The only way to remedy the problem would then be to drain the tank and add fresh gasoline. The best way to avoid phase separation over the winter (aside from emptying the tank) is to leave the tank 95-percent full (which allows for expansion) so that there's less moist air in the tank, less space for condensation to collect, and more gasoline to absorb whatever moisture does accumulate.

Myth #2: E10 attracts water, so it's important to install a water separator to prevent the water reaching the engine.

Mercury Marine, which recently hosted a Webinar on ethanol myths, noted that ethanol does not "grab water molecules out of the air." It is hydrophilic, which means ethanol holds water. With regular gasoline (E0) as well at E10, the primary cause of water collecting in tanks is condensation on tank walls. But unlike E0, which can absorb almost no moisture, E10 can hold up to half of one percent of water by volume, and the water molecules will dissolve in the fuel. The "solubilized" water will bypass the water separator and burn harmlessly through the engine. Only if phase separation were to occur would a water separator do its job, but by then the fuel itself would be the problem. The phase-separated water/ethanol mixture would settle on the bottom of the tank near the fuel pick-up and would quickly stall out or even damage your engine. And because ethanol is used to boost octane, the remaining (low-octane) gasoline at the top of the tank would also have the potential to damage your engine.

Note, however, that a fuel filter (10-micron) is essential to keep gunk from reaching your engine. Ethanol is a solvent that dissolves resins, rust, and dirt that have accumulated on older tank walls. Especially when you first make the transition to E10, it's important to carry spare filters and a galvanized bucket to store used filters prior to disposal. Even in new engines and tanks, E10 will sometimes form a mysterious gooey substance that will also clog filters. Richard Kolb, the manager of Emissions and Regulations for Volvo Penta, believes the goo is caused by water mixing with one or more of the 108 approved compounds that can be used in gasoline. These compounds vary among suppliers, so one solution is to change to a different brand of gasoline. Another is to use carburetor cleaner, which he says has sometimes remedied the problem.

Myth #3: Certain additives can prevent phase separation?

Both Gibbs and Simnick said that the additives that eliminate water may work incrementally to protect against phase separation, but Joe Simnick stressed that no additives will stand up to a good slug of water. Lew Gibbs added that the best way to prevent phase separation in E10 is to "keep it dry, keep it dry, keep it dry." That means keeping the tank filled to prevent condensation. Mercury Marine has also noted that, contrary to statements made by some companies that produce fuel additives, there are no additives that can make stale or phase-separated gasoline usable.

E10 is certainly not as trouble-free as E0, especially the first few tankfulls. But for newer engines, those built after about 1991, there's no reason the initial problems can't be overcome. No less an authority than Mercury Marine says, "After the transition period from E0, E10 may actually be a superior marine fuel as it tends to keep low levels of water moving through the fuel system, keeping the
system 'dry.'"

And from Mercury Marine......
Mercury Debunks More Ethanol Myths

Mercury Marine, the world's largest manufacturer of marine engines, recently held a webinar to debunk some of its own myths about ethanol. I attended with interest. The first myth was that there are fuel additives that can prevent all issues associated with ethanol-blended gasoline. For example, no fuel additive can prevent ethanol from acting like a solvent. The second myth was that fuel additives can make stale or phase-separated fuel useable. "Fuel cannot be rejuvenated," Mercury determined, and they noted that it's a myth that ethanol-blended fuels are bad and should be avoided. Here are some quotes from the Mercury Marine webinar.

"There is no active transfer mechanism for ethanol molecules to reach out and 'grab' water molecules out of the air. Under normal storage conditions, even in a vented fuel tank, it just does not happen at a level or rate that is relevant."
"Major multi-billion dollar companies with enormous resources have improved gasoline additives but there have been no recent breakthroughs involving 'magical technology.' Claims made by companies about 'space-age,' 'revolutionary,' or special proprietary technology should be looked at with a high degree of suspicion."
"E10 Ethanol absolutely IS an acceptable fuel for everyday use."
"E15 Ethanol absolutely IS NOT an acceptable fuel."
"After the transition period from E0, E10 may actually be a superior marine fuel as it tends to keep low levels of water moving through the fuel system, keeping the system 'dry.'"
"Don't immediately assume E10 is the problem."
 
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