How often should the lower unit oil be changed on an outboard motor?

Boating enthusiasts know how important it is to maintain their outboard motors to prevent costly breakdowns and repairs. One critical component that requires attention is the lower unit oil. But how often should you change it?

The general recommendation is to change the oil every 100 hours of operation or once a year, whichever comes first. However, it’s essential to check the manufacturer’s recommendations for your specific outboard motor.

Changing the lower unit oil is a simple process that you can perform yourself or have a professional do it for you. Before you begin, it’s essential to have the right tools and materials. You’ll need a drain pan, a funnel, the correct type of lower unit oil, and a new drain plug gasket.

Start by running the engine to warm up the oil. Then, turn off the engine, disconnect the fuel line, and remove the cowling to gain access to the lower unit.

Next, locate the drain plug and remove it using a wrench. Allow the old oil to drain completely into the drain pan. While the oil is draining, inspect the drain plug for any signs of damage or wear. Replace the drain plug gasket if necessary.

After the oil has drained, reinstall the drain plug and torque it to the manufacturer’s specifications. Then, locate the oil fill hole and place a funnel in it. Slowly pour in the correct amount and type of lower unit oil until it reaches the proper level indicated on the dipstick or sight glass.

Finally, reinstall the cowling, connect the fuel line, and start the engine to check for any leaks.

By following the manufacturer’s recommendations and changing the lower unit oil regularly, you can ensure the longevity and reliability of your outboard motor. Don’t skip this crucial maintenance task and risk damage to your engine. Take care of your motor, and it will take care of you while out on the water.

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