Introduction
Regular maintenance is the key to keeping your outboard motor reliable, efficient, and ready for every trip. But even experienced boaters make small mistakes that can lead to big problems—like overheating, poor fuel economy, or premature engine wear. Understanding what not to do is just as important as knowing what to do.
Here are the Top 10 Outboard Maintenance Mistakes most boat owners make—and how to avoid them.
1. Forgetting to Flush After Each Use
Failing to flush your outboard, especially after saltwater use, allows salt and debris to build up inside the cooling passages. Over time, this leads to corrosion and overheating issues.
Solution: Always flush your engine with fresh water for 5–10 minutes after every trip. Use a motor flusher or earmuffs to ensure proper water flow.
2. Skipping Oil Changes
Old or dirty oil breaks down and fails to lubricate properly, causing wear on internal parts. It can also thicken, reducing performance and increasing fuel use.
Solution: Change your outboard oil every 100 hours or at least once per season. Don’t forget the gearcase oil, too.
3. Running Without a Fuel Stabilizer
Modern fuel contains ethanol, which absorbs moisture and can separate over time, causing clogged injectors and poor performance.
Solution: Always add a fuel stabilizer before storing your boat or if you won’t run it for more than a couple of weeks.
4. Ignoring the Propeller and Shaft
Dings, bends, and fishing line wrapped around the prop shaft can cause vibration and lower your speed.
Solution: Remove the prop periodically, inspect for damage, and apply marine grease to the shaft before reinstalling.
5. Neglecting the Water Pump Impeller
The impeller is a small rubber part that keeps your engine cool by circulating water. If it fails, your motor can overheat in minutes.
Solution: Replace your impeller every 1–2 years or sooner if you notice weak water flow from the tell-tale stream.
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6. Using the Wrong Spark Plugs
Incorrect plug types or gaps cause misfiring, hard starts, and lower fuel efficiency.
Solution: Always use OEM-recommended spark plugs and check their gap with a feeler gauge before installation.
7. Storing the Engine Improperly
Leaving your motor tilted down or without fuel treatment during off-season storage leads to corrosion and gummed-up carburetors.
Solution: Store your engine upright, drain or stabilize fuel, and fog the cylinders if storing long-term.
8. Forgetting Battery Maintenance
Low or corroded battery terminals cause hard starts and electrical problems.
Solution: Keep terminals clean and tight, check voltage monthly, and charge before winter storage.
9. Over-Tightening Bolts or Spark Plugs
Excess torque can strip threads or crack components. Many outboard parts require precise torque settings.
Solution: Use a torque wrench and follow manufacturer specifications when tightening bolts, plugs, and filters.
10. Ignoring Warning Signs
Strange noises, hard starting, or reduced performance are your motor’s way of telling you something’s wrong. Waiting too long can turn a simple fix into a major repair.
Solution: Investigate issues early and don’t ignore alarms or overheating lights.
Bonus Tip: Follow a Maintenance Schedule
Keep a simple log of oil changes, impeller replacements, and seasonal checks. This not only helps you stay organized but can also increase your engine’s resale value.
Shop OEM Maintenance Parts at Boat Max Online ➜
Most outboard problems start with skipped maintenance or small oversights. By avoiding these 10 common mistakes, you’ll extend your motor’s life, save on fuel, and prevent costly repairs. Whether you’re maintaining a Suzuki or Honda outboard, regular care keeps you on the water longer and with peace of mind.