Survey: Ethanol major factor in engine damage

Most marine businesses are experiencing engine damage and other issues due to ethanol in the fuel supply, raising increased concerns about the growing use of E15.

Boating Industry surveyed readers of our print and digital editions about service department and warranty issues, including ethanol, in April. Respondents were a mix of dealers, manufacturers, marina owners and others.

(See the full results of our survey in the June issue of Boating Industry.)

Damage widespread

The vast majority of respondents reported seeing engine damage from ethanol, with 73 percent saying they’ve experienced it in their business. That number rises to 80 percent when we look at just dealers and marina/boatyard owners.

And it’s not a small portion of the engine work they’re seeing, either. Of those that have seen ethanol damage in their business, 14 percent say ethanol is responsible for more than half of the engine repairs they make. More than 60 percent say it causes more than 20 percent of the engine damage they experience.

While many marinas carry ethanol-free fuel, many consumers fill up at roadside stations – about two-thirds, a recent survey of BoatUS members found. At most stations, that is a 10 percent ethanol blend. That’s a level of ethanol that new engines can handle if run and cared for properly, but that does nothing about the large number of legacy engines out there.

Now, with 15 percent ethanol blends (E15) on the horizon, there is even more reason for concern. While not widely available across most of the country, it is spreading, especially in the Midwest.

Nearly 75 percent are very concerned about the use of E15 in the fuel supply and 93 percent described themselves as at least somewhat unconcerned. Only 7 percent aren’t worried about it.

Warranty work a challenge

While not related to ethanol directly, we also asked readers about their experience with warranty claims in the survey.

Overall, the majority of respondents — 64 percent — said they haven’t seen a change in warranty claims over the last year. Twenty-two percent said they are seeing more warranty claims and 14 percent said they are seeing fewer.

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  1. I own a boat repair and ethanol has become a real problem . We are seeing engine coming in with fuel problems more and more. Fuel lines are breaking down and the fuel is damaging the hole system. If they go to E15 the older engines will fail . the public will lose . most of them will not be able to replace there engines . everyone will lose from the repair shops to the people that make there living off of boating. This has to stop;

  2. Jonathan. Excellent article. One correction. Most marinas DO NOT sell ethanol-free gasoline as 10% ethanol blended gasoline (E10) is required by law in all states from North Carolina to Maine and most other major metropolitan areas or where fuel suppliers only offer E10. Ethanol free gasoline is only supplied in a few markets by a few gasoline refiners.

    Over 700 marinas sell ValvTect Marine Gasoline that is formulated with ValvTect Ethanol Gasoline Additive (VEGA); most are required to sell E10. Reports from these marinas indicate very few problems caused by E10 treated with VEGA. Same with boaters buying E10 from land based gas stations when they treat the fuel with VEGA or a similar ethanol fuel additive. Most problems are experienced when boaters use E10 and do not treat the fuel with an effective ethanol fuel additive, thus boaters should be educated to use an ethanol gasoline treatment with using E10.

    One must remember that E15 cannot “legally” be sold to boats, all non-highway equipment and most on-road vehicles. E15 pumps are required to be labeled as such. Almost all marine and automotive engine manufacturers’ warrantees do not allow use of E15, thus consumers (especially boaters) should be educated to avoid using this fuel even if it is less expensive.

  3. I’ve been a mechanic and in the past a gas station attendant. When ethanol/methanol was first introduced it destroyed fuel systems. Our shop thrived on alcohol related repairs. It hasn’t changed much in the last 25-30 years. The older machinery can’t stand up to it.
    Ivy Bent Resort and Marina.
    Stover, MO.

    1. Ethanol and methanol are 2 totally different products. One is oil based and harmful to the environment and fish. The other one is plant based and does not hurt the environment. Been using ethanol since it came out, have never had any problems. Actually,has helped several engines run better.

  4. For a few years it was harder and harder to get ethanol free gas. If you could find it the price was high and the octane low. Now it is much easier and the cost is about the same. We are still cautious not to get ethanol pre-blend because the octane will be real low. We sell 88 octane with the valv tect additive We depend on the revenue from our fleet of rental boats and we don’t want fuel issues. We see enough of those problems from folks who trailer their boats and buy car gas with ethanol.

  5. are there any fuel additives that can help if you cant get the v power fuel??? thanks Skip iam running a 250Verado Pro

  6. In my tiny Virginia (VA is north of North Carolina) county of just 8000 people, )and over 50 boat yards and marinas), I know of one land station and three marinas that sell non-ethanol fuel (which I use religiously in all of my off road and classic auto engines), I suspect there are more, at least one of which is 93 octane. I wonder, therefore, how does that square with the mandate for use of 10% ethanol? Of course I’m not questioning it, and can only hope more stations see the need for this counterweight to this disastrous debacle called E10.

    From a technical perspective, when my clients ask, I strongly recommend that they use non-ethanol fuel where available, and barring that, buy ValvTect fuel, or use an additive such as ValvTect or StaBil Ethanol Fuel Treatment religiously.

    Having said that, and referencing Jerry’s comments, while Valvtect VEGA is an effective treatment for this disease, the point of this article is to highlight the illness itself, the inherent deficiencies of ethanol laced gasoline and the millions of dollars of failures it has caused, (not to mention its inefficiency, it takes more energy to make a gallon of ethanol than is derived from it, the very definition of inefficient). It essentially means that neat, from the pump fuel, barring ValvTect of course, is no longer suitable for all but the newest marine (and so many other off road, classic car and other) engines, a scenario that is just technically unacceptable and inherently unjust, one wherein our lawmakers have let the boat owner public down.

    Bio-Diesel has its issues as well, however, it at least has efficacy on its side, it takes less energy to make a gallon of bio-diesel than is derived from it, making it palatable for those who consider energy independence a worthwhile goal. E10 virtually guarantees fuel system and engine problems, and it has nothing going for it to boot, it should never have been approved, and when it was users were not appropriately warned of its side effects by the Fed or fuel retailers. E15 would be a marine industry disaster of epic proportions, and while many say it couldn’t happen, many in our industry also said the luxury tax would never happen.

  7. I have been a marine mechanic and race engine builder of two and four stroke engines for the past 30+ years and have seen the progression of just how Ethanol has worked it’s way into the marine industry as a damaging force. There are many solutions to this problem! Ethanol is NOT going to go away, EVER! The politicians will tell you this if you ask the correct questions. I have seen 3 products that work to eliminate the ethanol issues in boating fuel systems. What’s funny is that the one we now swear by has no real market presence and is hard to come by unless you order it direct. The other two are available everywhere it seems, but they don’t do what my favorite does. The two that work well for the ethanol issues alone are Star-tron and Stabil. However, they do not offer the performance increase for stock or modified engines that the Adrenaline Marine does. It is very, very noticeable at all rpm’s and especially at and idle. The other thing this product does is clean crap out of the fuel system. I mean the gum and crud that is left in carbs and pumps from storage and sitting. If it runs so so and you put some of their product in the tank it will run way better in 10 minutes. You will also be hard pressed to get gas station ethanol fuel to go bad anytime soon with this product in it as well. I just wish I would have known about this product a long time ago, could have saved a lot more people from going through ethanol related grief.

  8. What exactly does the ethanol do to the engine? I know it can ruin hoses and gaskets that are not made to withstand it. Anything else?

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