Beware of E15 Fuel: A Risk to Your Engines

New EPA policies now allow E15 fuel to be sold year-round, making it essential for boaters and powersports enthusiasts to pay close attention when refueling. Choosing the wrong fuel can damage marine, motorcycle, ATV, or UTV engines and may even void your warranty.

What is E15 Fuel?

E15 is a gasoline blend containing 15% ethanol, derived from corn or other grains. Historically, it was restricted during summer months due to its high volatility, which contributes to smog formation in hot weather. However, starting in 2022, the EPA issued waivers allowing E15 sales year-round as a response to rising fuel prices.

Why is E15 Risky for Your Engines?

While E15 may work for some road vehicles, it is not designed for most marine and recreational engines. Ethanol absorbs moisture from the air, which can lead to:

• Corrosion of metal components
• Deterioration of plastic or rubber parts
• Fuel leakage through rubber fuel lines
• Starting and operational difficulties

High ethanol levels also increase the risk of water accumulation in the fuel tank, especially during long storage periods, posing a significant threat to marine and powersports engines.

Warranty Implications

Using fuel with more than 10% ethanol (such as E15) may void your manufacturer’s warranty. Engine manufacturers have long warned about ethanol-related damage, but the increased availability of E15 heightens the risk of accidental use due to mislabeling or lack of attention at the pump.

Tips for Safe Refueling

• Always check ethanol-content labels at the pump.
• Use only fuel with 10% ethanol or less unless your manufacturer specifies otherwise.
• Take your time to read the pump information before filling your tank, even if you’re in a hurry.

Following these simple steps can save you costly repairs and extend your engine’s lifespan.

Maintenance Tips for Mercury OptiMax Outboards

Mercury® OptiMax® outboards are renowned for their power and efficiency. With regular maintenance, your OptiMax engine, especially the 3.0-liter Pro XS® models, can deliver exceptional performance for years to come.

1. Follow the Owner’s Manual

Strictly adhering to the maintenance schedule outlined in your owner’s manual is critical to avoiding costly repairs and ensuring your engine’s reliability. If you don’t have a manual, download a PDF version from Mercury Marine or order a printed copy from an authorized Mercury dealer.

2. Use the Right Oil

The manual recommends Quicksilver Synthetic Blend Performance DFI 2-Stroke oil, which is specifically formulated for OptiMax engines. This oil minimizes carbon buildup, reduces piston wear, and optimizes engine performance. Using inferior oil can cause severe engine damage.

3. Treat Your Fuel

To keep fuel injectors clean, add Quicksilver Quickleen® at every fill-up. This cleaner removes carbon deposits from injectors, spark plugs, and piston crowns. Follow the bottle’s instructions for optimal results.

4. Replace the Fuel Filter with Proper Tools

Fuel filter replacement is part of the annual or 100-hour maintenance. Use the Quicksilver Fuel Filter Tool (p.n. 91‑896661) to safely remove and replace the filter without damaging the plastic tabs. Apply engine oil or Quicksilver 2-4-C Marine Grease to the filter’s O-rings before installation.

5. Drain the Vapor Separator Tank

Follow the instructions in the manual to drain water from the Vapor Separator Tank (VST). This helps maintain engine performance and prevents moisture-related issues.

Regular Maintenance for Long-Term Enjoyment

With proper care and the right tools, your Mercury OptiMax outboard will continue to provide reliable power and performance for years of on-water enjoyment.

How to Change Oil in Your Mercury Outboard Engine: A Practical Guide

Oil is the lifeblood of your Mercury® outboard engine. Regularly changing the oil and filter after 100 hours of use or at least once a year is essential maintenance. Many boaters perform this task during winterization or before off-season storage to ensure their engine is ready for the next season.

1. Choose the Right Oil and Filter

Using the correct oil and filter as outlined in your owner’s manual is vital. Quicksilver marine oils, available in mineral, synthetic, and synthetic blend formulations, are designed to protect marine engines from wear and corrosion. Quicksilver filters ensure high-quality filtration and are built to prevent leaks or collapse.

2. Essential Tools

• Wrench or socket for drain plug
• Oil filter wrench
• Funnel
• Clean rags and gloves
• Oil pump or drain kit
• Oil catch pan

3. Draining the Oil

1. Trim the outboard past vertical for one minute to drain trapped oil.
2. Return the outboard to vertical and remove the cowl.
3. Use a pump to extract oil through the dipstick or locate the drain plug to release oil into a catch pan.
4. Tighten the drain plug and dispose of the oil properly.

4. Replacing the Filter

1. Locate the oil filter (usually on the starboard side).
2. Place a rag below the filter, remove it, and lubricate the new filter’s gasket.
3. Thread the new filter and tighten securely.

5. Adding Fresh Oil

1. Check the drain plug, add new oil with a funnel, and check the level with the dipstick.
2. Idle the engine to ensure no leaks, then recheck the oil level.

Pro Tip: Check for Contaminants

Look for signs of water (milky oil) or fuel (strong odor) in your used oil. If contamination is found, consult a Mercury dealer.

By following these simple steps and using high-quality Quicksilver lubricants and filters, you’ll keep your Mercury outboard running at its best.

How to Winterize Your Mercury Pro XS Outboard: Complete Guide

At the end of the boating season, it’s easy to pull your boat out of the water and forget about it until spring. Don’t make that mistake. Spending a few hours winterizing your outboard can save you time and money when the next season begins.

1. Treat the Fuel System

Replace the fuel filter and add a stabilizer like Quicksilver Quickstor® to fresh fuel (non-ethanol if available). Run the engine for a few minutes to circulate the stabilized fuel through the system.

2. Change the Oil and Filter

Change the oil and filter every 100 hours or once per year, regardless of usage. Used oil can contain moisture and acids that cause corrosion. Quicksilver Oil Change Kits include oil, a filter, and a drain plug seal, making the process easier.

3. Replace Gearcase Lubricant

Change the gearcase lubricant every season. Milky lube may indicate water contamination due to a damaged seal. If clear, refill with Quicksilver Premium Gear Lube following your manual’s instructions.

4. Protect Internal Components

Apply fogging oil or engine oil to prevent internal corrosion. Remove spark plugs, spray oil into cylinders, rotate the flywheel manually, and reinstall the spark plugs.

Additional Tips

• Grease the prop shaft: Use Quicksilver 2-4-C marine grease on the prop shaft and steering mechanisms.
• Inspect anodes: Clean or replace worn anodes to prevent corrosion.
• Apply corrosion protection: Spray Quicksilver Corrosion Guard on exposed parts, avoiding anodes and air intakes.
• Store upright: Keep the engine vertical to drain water completely.
• Batteries: Fully charge, disconnect, and store batteries on a maintenance charger.

Following these steps ensures your outboard is ready for the next boating season.