The best maintenance tip for your diesel engine is to use it. Letting your diesel powered boat or any boat for that matter, sit at the dock or in storage is the worst possible way to maintain its value and operational longevity. Diesel engines do best when you run them on a regular basis. Letting them sit and idle to charge the batteries is better than not running them at all.

Here are a few tips to help you maintain your marine diesel.

  • Your marine diesel uses seawater to keep it cool. When it is left idle the seawater remains in the system and can cause corrosion of the cooling system due to condensation that builds up on the inside of the manifolds. Over time, this can cause sludge, keeping your engine from cooling properly. If you run the engine frequently this is not a problem. If you run it infrequently, moisture can end up in the engine sump contaminating the oil. Water in the oil can cause you maintenance issues and shorten its usable life.
  • Strainers that the seawater flows through going to your engine need to be kept clean. It is also an important part of marine diesel engine maintenance. Strainers are necessary to keep sea grass and other foreign objects from entering the water pump. If your diesel powered boat does not have a filtration system for its seawater intake, it is advisable to add one.
  • Oil changes on your car are determined by the number of miles that your drive. Oil changes on marine diesel engines, on the other hand, are measured by hours. The oil in your engine should be changed every 150 hours or annually if you do not meet the 150 hour mark in a year’s time.
  • Topping off your fuel tanks when leaving the boat unused will aid in keeping the fuel clean and preventing fungus and moisture build up in the tanks. There is no way to prevent moisture and fungus from entering the intakes of your engine. It must breath or it will not run. In doing so, it takes in bacteria from the air, as well as moisture. The best that you can do is to take preventative measures. Properly using a biocide mix with your fuel and a high quality air filter and fuel filter, which is made for your engine, will help with this issue.
  • Using a fuel filter with a clear glass bowl, such as a Racor Primary fuel filter, will enable you to see if there is water in your fuel. This also allows you to drain off containment’s that can corrupt your fuel before they become an issue.
  • Using a secondary filter will also aid in preventing fuel contamination.
  • Fuel polishing, also called a fuel cleaning system, uses a pump to take fuel from your storage tanks and filters it through water particle filters or magnetic fluid conditioners (MFC). This method of fuel cleaning can remove impurities and return your diesel to your tanks as clean as it was when you first filled them. Fuel polishing, a superior method of fuel maintenance, can also provide better fuel economy.

Clean fuel and cooling systems are your best defense against engine breakdowns of your diesel engine. Following these tips will help you keep your Volvo Penta marine diesel engines running longer, cleaner and more efficiently. In the long run these maintenance steps will keep you from having to make major mechanical repairs and although there is some upfront cost to their utilization the long term benefits could save you thousands of dollars in major work and breakdowns.