What Fuel Should I Use in My Boat?
Top Tips from Muskoka Marinas to Protect Your Engine and Maximize Performance
One of the most common questions we hear from boat owners is: “What kind of fuel should I use in my boat?”
It’s a great question—and one that could save you from costly repairs, poor performance, and a ruined day on the lake.
At Muskoka Marinas, fuel-related engine issues are among the top problems our service department deals with. Whether it’s from contaminated boat fuel, ethanol-related damage, or poor fuel storage, these problems are almost always preventable.
Let’s walk through what you need to know to choose the best fuel for your boat, keep your fuel system clean, and avoid mid-season breakdowns.
Why Fuel Quality Matters for Your Boat Engine
The type of fuel you use has a big impact on your boat’s performance and long-term reliability. Many issues stem from:
Old or poorly stored fuel in jerry cans
Leaky or loose boat fuel caps
Boat covers that direct water into fuel vents
Fuel with too much ethanol
Ethanol absorbs moisture, and that moisture leads to phase separation, corrosion, and fuel system failure. That’s why we always recommend using premium, ethanol-free marine fuel.
At Muskoka Marinas, we offer non-ethanol premium fuel at both of our locations—and we rarely see fuel-related issues in boats that fuel up with us.
But we also understand that it’s not always convenient to fill up at the marina. So if you’re fueling up elsewhere, here’s what to do:
1. Use Ethanol-Free Marine Fuel Whenever Possible
Using ethanol-free gas is one of the easiest ways to avoid water contamination and engine damage. Aim for at least mid-grade fuel, and premium fuel is ideal for optimal performance.
Even if your engine manual says “regular is okay,” remember: that’s a minimum requirement, not a performance recommendation.
If you can, always use non-ethanol fuel for boats.
2. Buy Fuel from High-Turnover Gas Stations
Fresh fuel matters. Buy gas from a busy station with high fuel turnover, especially if you're not near a marina.
⚠️ Warning: In some rural or cottage areas, premium and mid-grade gas may sit longer in underground tanks, which could result in degraded fuel. In that case, regular fuel might actually be fresher—but always check the maximum ethanol rating your boat engine can handle.
3. Store Boat Fuel the Right Way
Improper fuel storage is one of the biggest causes of fuel contamination. Follow these tips to store your boat fuel safely:
Keep gas cans in a cool, shaded, and well-ventilated area
Ensure vents are closed tightly—especially with ethanol-blended fuel
Avoid adding gas-line antifreeze or additives that increase ethanol levels
Label containers and rotate stock regularly
Moisture absorption leads to water in your boat fuel, which can wreak havoc on your system.
4. Use a Fuel Stabilizer During Storage or Downtime
If your boat won’t be in use for a few weeks or longer, add a fuel stabilizer to protect the fuel system. We recommend Mercury Quickstore, available at both Muskoka Marinas locations.
Another pro tip: don’t fill your tank before you leave the lake. Instead, add fresh fuel just before your next outing. This reduces the risk of stale or separated fuel sitting in your system.
Final Thoughts: Keep Your Boat Running Smooth with the Right Fuel
Using the wrong fuel—or storing it incorrectly—can lead to unnecessary repairs, poor performance, and frustrating delays. By following these tips and fueling up with ethanol-free marine fuel whenever possible, you’ll protect your investment and enjoy smoother, safer boating all season long.
Have questions about your boat’s fuel system or fuel options? Our expert service team is here to help.
✅ Premium Non-Ethanol Marine Fuel Available at Muskoka Marinas
📍 Visit us at Skeleton Lake or Lake Rosseau in Windermere for clean, high-quality boat fuel.