Just like with any vehicle, there are a whole range of fixes and maintenance tasks that go along with owning a boat. To save a little money, it's always nice to know which of of these chores can be handled on your own. Not only will it save you money, it is just more convenient than having to haul your boat out to a mechanics for every little thing.
Don't worry, trying to maintain your own marine electrical services is probably too complicated for the average boat-owner so we will stick to the more typical DIY chores you can start with.
The ever popular oil change can apply to most motor boats and is definitely something you can do on your own, just like you would with a car or a motorcycle. There are a few differences when dealing with boats though. Smaller engines (usually referred to as 2-stroke) do not require oil changes like larger (4-stroke) engines do. You have to know what sort of motor you have before worrying about oil changes.
The reason is that a 2-stroke engine doesn't have a separate oil supply as the oil is actually mixed in with the gas when you fill up the tank. It keeps things lubricated, and the oil is literally replaced every time you gas up. On the other hand, a 4-stroke motor does have an internal oil supply that gets changed out.
Now that we've explained, that it's an easy chore to change the oil in a 4-stroke boat motor. Open up the reservoir, and use a pan to collect the old oil. Once it's done draining, you can remove the oil filter with a clean one while you're at it. Wipe up any drips from the openings, close up the drainage hole and refill with a fresh tank of oil. Very simple.
Unless you live in a warm climate where you can go boating for 12 months of the year, you will probably need to "winterize" your boat in the fall. This means a handful of small chores to prepare your boat for sitting idle in the cold for the season. Change the oil, and drain out any water in the cooling system (this second one applies to larger in-board engines only). Water should also be drained from any onboard plumbing systems (taps, toilets, etc.). Add a fuel stabilizer to the gas tank and let it run for a few minutes to let it work its way through the engine.
Another way to winterize the engine is with an aerosol fogger. Get the brand recommended for your engine, and spray the material into the air intake as the engine is running until the can is empty. This leaves a light coating of lubricant through the engine for protection over the winter. Lastly, remove cushions or any other fabric components and store them inside.
Just because you don't see down in the bilge doesn't mean you should ignore it. If you let dirty water build up, your boat will start to really smell and you also want to make sure that the pump is working as well. For the pump, periodically move the float upward by hand and make sure the pump kicks in. If not, that means if the water level gets high, the pump won't activate so get it checked out or repaired. Once a season, use a biodegradable cleaner down there and give it all a good scrub down too.