Winterize your outboard to make it purr in the spring.
Does your motor sleep in the garage from December to late March? If so, you may want to give it a bit of TLC before putting it to bed; otherwise, it’s likely to be a bit cranky when it comes time to wake up in the spring.
The biggest problem with motors that have been stored is fuel evaporating and leaving behind gunk that clogs up the system. To avoid this, add a fuel conditioner or preservative to the tank. Attach a water hose to the flush fitting, then run the motor at fast-idle for five minutes to make sure the conditioner goes throughout the fuel system. Use extreme care when performing this operation; make sure the motor is in neutral and stays there to avoid the danger of the whirling prop. Most technicians also recommend filling your gas tank to the top with fresh fuel before winter storage-this prevents water from condensing inside the tank.
Next, make sure there’s no water left in the cooling system by removing the hose, tilting down the lower unit to vertical and letting it drain thoroughly. Don’t store any motor with water in the water jacket or you could have problems later if the motor is exposed to freezing temperatures.
Use a “fogging” spray to put a light film of oil on the interior parts of an outboard. This will protect the motor from rust and sticking. Some sprays are injected into the air intake as you turn the motor over; others are designed to be sprayed directly into the spark-plug holes. Don’t omit this step or condensation will almost surely cause rust on cylinder walls and piston rings, leading to premature wear when you start up in spring.
This is a great time to drain the lower-unit oil. You should change the oil at least once a year anyway. Make sure you get out any water that may be in the unit before you store the motor. Replace the oil with fresh lube recommended by your motor manufacturer. Add lube to the steering tube on the motor. (Clean this shaft with solvent first if it has old grease dried in place.) Also clean and lube the rams on your motor’s tilt/trim system.
Finally, disconnect the battery, clean all connections and terminals and coat them with grease. Refill the cells if the battery isn’t maintenance-free. Recharge the battery, then store it where it won’t be subject to extended freezing temperatures. Recharge it every 30 days and it will be ready to roll once the bass begin to bite again in the spring.