Restricted Water Flow

The Fourth of Seven Boating Systems Tips

Is that smoke or steam coming from your boat’s exhaust system?

Not only does your boat float in water but it also uses that same raw water to cool your engine(s). It pulls the water into the pump and flows through different heat exchangers and out through the exhaust hose back into the water where you are floating.

The open circuit raw water cooling system is last used to cool the muffler and exhaust hose overboard. The engine can heat the temperature of the exhaust gases over 1000 degrees F. Temperatures that high can melt a marine quality exhaust hose if it is not cooled properly. So before the gases enter the hose they are mixed with raw water to cool down below 200 degrees F. Pretty kewl huh?

As soon as you start your engine you should check the exhaust water flow to be sure the engines and hoses are being cooled effectively. It is typical to see water pulsing from the exhaust port either on the side or the stern of your boat. Learn what your exhaust water flow looks like- volume, strength, pulsing, stream. If your volume is decreased check your strainer for plugging or stop the engine and check the impeller.

Next post we will discover the problem by inspecting our impeller in the video Impeller Trouble Shooting. Stay tuned!