Ten years into the ethanol era for fuel in the United States, we’re finding that more and more marinas are selling ethanol gas for marine use. This gas is a maximum of 10% ethanol content because boat engine manufacturers like Mercury still recommend against using E15.
Ethanol blend gasoline still doesn’t play well in water-rich environments. If you’ve been around the Bell blog for any length of time, you’ve read the discussion about how water induces phase separation and destruction of fuel quality in ethanol blends. That same danger in marine environments is obvious.
What about fuel-water separators? These standard-issue items for boats can’t do anything about the dissolved water that forms in ethanol-blend gasoline.
The main remedy for boat fuel health is to use a fuel treatment that addresses ethanol problems. In deciding between the myriad of choices out there (how are you supposed to pick the best one when they all look the same?), look for one that can control water in gasoline without using alcohol, while providing injector detergency and protection for boat fuel system parts from destructive ethanol solvency.
Keeping on top of this problem is worth your while as a boat owner. Repair estimates for ethanol damage typically run around $1,000 per time. And lest ethanol advocates try to downplay this issue, if you talk to those in the boating industry itself, it’s pretty clear they recognize the upswing in damage from ethanol. In 2015, 73% of respondents indicated they had seen engine damage to boats caused by ethanol. A year later, that figure was 87%. These respondents came from the boat repair industry, so they tend to pay attention to these things.