Boat noise laws thrown out?

NightWing · 08-27-2004, 05:29 PM

Thank you Mee-n-Mac for helping clarify my statement. I was trying to explain to Madrasahs that he was not clear how an adjustable exhaust system operates. Cooling water is introduced into the exhaust stream, regardless if the exit point is above or below the water line. Notice I didn't say "muffling water" because water alone does not meet the state definition of a muffler.

Now, to shut that water flow off, even for a short time, would seriously overheat the exhaust system from the risers on back to the exit point. Most through hull exhaust systems have some type of rubber connection, sometimes a length of hose or a small "hump hose" which allows for slight movement and misalignment. True, some of the faster, high performance boats have solid systems with nothing but stainless steel piping. Still, those systems require cooling water to keep exhaust temperature under control.

As far as being a fire hazard, consider that the exhaust system on a boat is not out in the airflow, like an automobile. The entire powerplant is under cover in a compartment with marginal ventilation, and that compartment is of fiberglass or wooden construction, both items well suited for a nice, hot fire.

That being said, adjustable exhaust systems, whether named Captain's Call, Silent Choice, or Quick and Quiet II Plus, all share a similar method of allowing the exhaust to exit, un-muffled, through the hull or transom, instead of through the lower unit under water. That similarity is a diverter plate in each exhaust pipe and they are operated with various types of solenoids or cylinders and are controlled either by the operator or by some type of basic engine management system. Again, those adjustable devices are not legal in New Hampshire waters.

Finally, I would like to point out that I am not a "Big Boater".

08-27-2004, 05:29 PM	#11
NightWing Senior Member Join Date: Aug 2004 Posts: 410 Thanks: 4 Thanked 6 Times in 6 Posts	Thank you Mee-n-Mac for helping clarify my statement. I was trying to explain to Madrasahs that he was not clear how an adjustable exhaust system operates. Cooling water is introduced into the exhaust stream, regardless if the exit point is above or below the water line. Notice I didn't say "muffling water" because water alone does not meet the state definition of a muffler. Now, to shut that water flow off, even for a short time, would seriously overheat the exhaust system from the risers on back to the exit point. Most through hull exhaust systems have some type of rubber connection, sometimes a length of hose or a small "hump hose" which allows for slight movement and misalignment. True, some of the faster, high performance boats have solid systems with nothing but stainless steel piping. Still, those systems require cooling water to keep exhaust temperature under control. As far as being a fire hazard, consider that the exhaust system on a boat is not out in the airflow, like an automobile. The entire powerplant is under cover in a compartment with marginal ventilation, and that compartment is of fiberglass or wooden construction, both items well suited for a nice, hot fire. That being said, adjustable exhaust systems, whether named Captain's Call, Silent Choice, or Quick and Quiet II Plus, all share a similar method of allowing the exhaust to exit, un-muffled, through the hull or transom, instead of through the lower unit under water. That similarity is a diverter plate in each exhaust pipe and they are operated with various types of solenoids or cylinders and are controlled either by the operator or by some type of basic engine management system. Again, those adjustable devices are not legal in New Hampshire waters. Finally, I would like to point out that I am not a "Big Boater".