New exhaust system

During the survey, Bob pointed out the rusting stainless steel exhaust in the starboard cockpit locker. It had been weeping for some time and the steel was starting to go.  He said:   "Stainless steel exhaust pipe elbow and riser (as seen from starboard lazarette) is badly rusted and requires close inspection and repair or replacement as required."

After consulting with a few people we decided to pull it out of the boat and see how much it would cost to fabricate a replacement. Earl from Destache Yacht Service disconnected the long stainless steel exhaust system and through a heroic effort was able to get it out of the boat.  Bradley then took it to Chingon CMF in San Diego for a quote.  Their price is $1940.58, a sizable chunk of the boat kitty... but it is stainless steel!

I had been trying to figure out how the exhaust system worked.  On Platypus the hot gas and coolant mixes in a big mixing elbow on the side of the engine. From there it goes to a big round bucket of a muffler then out through the transom.   On Traveler the exhaust and coolant are not combined near the engine.  The exhaust goes into the center of a jacketed stainless steel pipe and the coolant travels through the jacket.  This jacketed pipe runs all the way aft to the bottom of the starboard cockpit locker then does a 90 degree turn vertical topping out just short of the cockpit seat.  There the gas and liquid are mixed and dumped overboard via a sturdy rubber hose, thru hull, and valve.  Here is my crude drawing. Click on it for a larger view.....