Hi all, Last week at the shop a Post went down a few days after launch. It went down in less than 2 minutes. The cause was that the port muffler exploded. The hole was 2 as large as the outlet through the transom 8". The owner stats they were getting ready for sea trial. The generator was running, they started the port engine (DDA 6-71TA) within in seconds they heard a loud bang, saw smoke. The boat started down immediately, they got everbody off. My thought is since the exhaust goes through the transom at 8", the muffler is approx. 24" long by 24" diameter. Maybe the muffler was full of water and when the started, the pressure created to push the water out the 8" hole was too great and the muffler gave way. Only problem with this thought is that a lot of boats are rigged this way and don't sink. Any thoughts?