powerboat 187125 1920

Outboard: 5 tips against engine breakdowns


If the engine is happy, the owner is happy too. Charles Plueddeman reveals how you can get your bike ready for a good start to the season.

Modern outboards are actually pretty reliable. With clean fuel and a good spark, there is little that can go wrong as long as you don’t scrape the bottom with the propeller. Service experts confirm that with the electronically controlled, lower-emission 4-stroke outboards with gasoline injection and two-stroke engines with direct gasoline injection, it is now the batteries and the fuel that are most likely to cause problems. But these tips should help you keep your engine fit for the coming season.

  1. Service the fuel: service technicians say gasoline sometimes starts to oxidize within 2 weeks. This means that boats that are not used for several weeks can have dirty carburetors, which can have a negative impact on the next trip. You can get the freshest petrol at gas stations that are busy. (In Italy, by the way, this also applies to coffee). Ethanol should be avoided because older machines in particular were not designed for it. If this is not possible, try to use gasoline with the lowest possible ethanol content. If you don’t run all of the gasoline immediately, add a stabilizer. If you leave the boat unused for more than a few weeks, add stabilized fuel and fill the tank full to avoid condensation.
  2. Filter the fuel: Even if the engine has its own gasoline filter, consider installing a separate filter between the engine and the tank. Especially if you need to fill up with gasoline that has been mixed with ethanol. A replaceable filter element removes water and impurities from the fuel. One uses e.g. 10 micron filters that must be matched to the capacity of the fuel pump.
  3. Pamper your battery: If the battery has been more than a few seasons under its belt and it was not connected to a charger during winter storage, a new battery may be due. Otherwise, you should check the cable connections to make sure that they are clean and secure. The battery should also be mounted in a box and lashed down so that it stays secure while driving. If your boat has a battery switch, turn it off after using the boat to prevent accidental discharge. If the boat is not going to be used for an extended period of time and you have an electrical outlet nearby, the battery should remain connected to a charger.
  4. Check the propeller: nicks and nicks in the propeller impair driving performance and should be repaired by a specialist. A propeller with a bent wing must be replaced immediately, because it makes the screw unbalanced, which can lead to expensive defects. On smaller machines with tiller or cable control you can feel a bent propeller blade as an additional vibration while driving, a bit like an imbalanced wheel on a car. Hydraulic steering systems on modern and larger boats mask this problem. An unbalanced propeller causes the shaft to flutter, which can lead to gear damage, or a leak in the shaft seal, which is also bad for the gear and bearings. This can be tested simply by starting the engine (with the ignition breaker removed) in idle while the boat is on the trailer or in the bracket. If you then shift into gear and turn the propeller, you can tell whether it is running out of round. Don’t forget that touching the ground in the mud can bend the wings without scratching the edges. If in doubt, ask a specialist workshop.
  5. Shaft and Seals: Fishing line wrapped around the propeller is a common problem. The line collects between the propeller and the shaft seal. The thrust of the propeller can push the line into the seal and damage it. This allows water to penetrate the gear unit and damage it. This happens within a few minutes and involves a very expensive repair. With a little practice you can pull off the propeller and inspect the shaft for unwanted fishing lines. But it is best not to throw unnecessary fishing lines overboard in the first place.

Bonus tip: Never start the engine when it is not in the water unless you have connected a garden hose to flush the engine. A few seconds of operation would ruin the water pump’s rubber impeller, overheating the engine, creating very costly problems and inconveniences.

How useful was this post?

Click on a star to rate it!

Average rating 0 / 5. Vote count: 0

No votes so far! Be the first to rate this post.


Leave a Comment

Your email address will not be published. Required fields are marked *