Not many people who own bass boats or even other style boats with outboard engines realize the importance of the engine cooling systems.

Many of us are all too happy to slide the boat off the trailer sucessfully with no problems, fire up the engine and then take off for a fun day of bass fishing. Still there's even more of us that don't ever think about the cooling systems on our outboards. Cooling system you may say?

All outboard engines have water pumps, thermostats, and impellers built into them, and these three parts play a major role in the sucess or failure of the engines cooling system. There are also a few other parts that comprise the cooling system which we'll discuss in a more in depth view of the cooling systems of outboards in a follow up article. For now we'll learn the basics of the cooling system.

It all begins with the water pump. The main job of the pump is to pump water from the lake, river, or other body of water through the engine cooling it off as the engine runs. The impeller is a little rubber star fish shaped component which spins and dispenses water from the pump through the engine where it then passes through the thermostats. The thermostats stay in a closed position disallowing too much water to circulate until the engine becomes hot enough to need a more thorough stream of water being pumped through.

Most professional outboard mechanics suggest having the water pump changed at least every 2 years. The impeller and the thermostats changed once a year. The impeller goes through the most wear and tear because of the material it is made of. The thermostats normally suffer wear and tear due to the increased temperature of the water which circulates through them, thus wearing them out at a fast rate.

All outboard engines are equipped with a pump out hole located on the back of the engine just above the water line. This hole is referred to as the "Tell Tale" hole, and it can tell us alot about the way our outboard is cooling or not cooling.

Normal exit of water from the tell tale is a steady stream of luke warm water streaming and flowing freely from the hole. You can easily see this stream flowing if you look at the back of the engine while the engine is running. A sure sign of cooling malfunction would be to notice no stream of water, a very weak stream, or just spats and or steam shooting from the tell tale.

Most of the time this is a sure sign that the impeller, water pump, or thermostat has worn out and needs replacing. Running the engine in this condition is a sure-fire way to find yourself at the local repair shop or even worse, at the local outboard retailer buying a new engine with all brand new parts in it!

Now to avoid the trip to the new engine dealer, and to avoid any more serious damage, simply shut the engine down and get the boat back to the trailer, dock, or marina. If you're good with hand tools like wrenches, pliers, screw drivers, and ratchet sets, you can buy a repair manual for your outboard motor and perform the repairs yourself. Of course you can drop the boat off at your local repair shop to have it all fixed up for you.

Hopefully your day on the water has'nt left you too far from the launch site when you discover the engine cooling system has failed. It's not a wise decision to try to run the engine while its overheating. This shall be left up to your own judgement as to what is needed to be done to get off the water and back to the trailer, marina, or dock area to perform the necessary repairs to the outboard.

Many professional repair mechanics advise to avoid these problems, simply have the 3 major components replaced on a regular basis. Naturally, the more the engine is used,the more often this should be done.

Keep your boat and motor in top shape before you hit the water and you'll always have a great day and be able to return safely!