Marine Engine Maintenance Tips

To keep your vessel moving on the water, start by maintaining your engine. Basic maintenance on your engine can reduce downtime and minimize overall owning and operating costs. Below are a few do-it-yourself tips to routinely perform before you head out for the waves.

#1: Use Antifreeze

Antifreeze is used to protect the engine coolant from freezing. In areas of the world where the temperature drops below 32 degrees F (0 degrees C), at least a 50 percent glycol concentration (antifreeze) is needed to avoid cracked blocks. Antifreeze also raises the boiling point of water. As such, a minimum of 30 percent glycol concentration is recommended in warm climates for protection against engine overheating

#2: Check & Clean Your Battery

Batteries are required to do more and more on modern boats, including starting engines and powering radios, radar, lights, pumps and other electronics. Batteries have a finite life, which depends in part on the quality built in by the manufacturer. Regardless of the type of battery in your boat, there are some basic steps you can take to keep it working properly:

  • Make sure the battery is securely mounted
  • Clean battery surfaces
  • Check battery cable connections weekly
  • Visually inspect all cables
  • Inspect all starter connections 
  • Check charging circuit connections
  • Check electrolyte levels and state of charge
  • Track discharging levels

#3: Use Proper Engine Fluids

The first step for critical cooling system care is making sure you’re using the proper fluids. Either distilled or deionized water should be used with approved antifreeze and approved supplemental coolant additive or rust inhibitor. (Fishermen in warmer climates don’t need to use antifreeze, but must still use the coolant conditioners.) Use a low-silicate antifreeze that meets one of the following specifications: GM 6038-M or ASTM #D4985. The fluid in the jacket water cooling system should not consist of plain tap water or water which has been “softened” by a domestic water softener. Tap water is not recommended for engine cooling systems because of additives, contaminants and other chemicals (such as salt, chlorides, sulfates, etc.) found in the water.


C12 Diesel Marine Propulsion Engines

The C12 Diesel Marine Propulsion Engines takes full advantage of the electronically controlled unit injection fuel system, resulting in an environmentally friendly engine with outstanding performance and fuel economy. There is also a wide range of optional equipment available to meet the needs of your marine commercial or pleasure craft application.

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Vessel Still Powered by Original 30-Year-Old Cat® Engines

A vessel in the UK, built to help save lives at sea for the Royal National Lifeboat Institute, still relies on the original Cat® D343 engines to power the vessel.

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