- 1). Dump a bottle of fuel stabilizer into your fuel tank just before you take your boat out for the last time. The "motion of the ocean" will mix the stabilizer into the fuel and the fuel pump will distribute it throughout your fuel system. After you trailer your boat and return home, unscrew the petcock on the bottom of the fuel tank drain and allow the water trap to drain into an oil drain pan until you see fuel draining from the trap.
- 2). Remove the propeller, either by removing the propeller nut or by removing the Allen screw in the center of the propeller cone, depending on the type of propeller your Penta is equipped with. Grease the propeller shaft's splines with waterproof white marine grease. Replace the nuts, spacers and washers on the shaft and send the propeller to the propeller shop for repairs, refacing and refinishing.
- 3). Connect a garden hose to the engine flush port---the hose with a blue plug on the starboard rear of the motor. Turn on the garden hose full force and start the engine. Unplug the seawater suction hose on the starboard side of the stern drive and plunge its end into a bucket filled with a half-and-half mixture of anticorrosive antifreeze and water, allowing the motor to run while the antifreeze is pulled into the motor.
- 4). Spray fogging oil into the carburetor until the engine chokes and stalls. Turn off the ignition. Pull the manifold drain plug. Pull a cylinder block drain on each side of the motor before unclamping the manifold hoses, the longest hose from the thermostat and the largest hose on the water pump. All of these will remain unconnected during storage. Reconnect the sea water suction hose to the stern drive.
- 5). Remove the dipstick and insert the probe of your oil pump through the dipstick tube, until you feel the probe "hit bottom" in the oil pan. Pump the oil out, change the oil filter and change the primary and secondary fuel filters.
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