BREAKAGE OF EXHAUST GAS MANIFOLD BELLOWS :
The ship was on its voyage from New Zealand to Australia. New Plymouth to Melbourne. It was second day voyage during midnight @ 0100 hrs there emanated some noise between third and fourth units of the main engine. That noise was coming continuously from that time onwards. 3/E could not reason out the exact spot on the machinery from where the noise came, he called second engineer to find out the problem. He inspected all the units and he also was not able to spot the cause. Then chief engineer was informed, who later came to the engine room and reduced the rpm of M/E after informing bridge. When the ship was going on half ahead the sound which was coming earlier disappeared. Again when the engine was made to full ahead that same noise occurred. Since it was on time charter chief engineer was not interested in stopping the ship for maintenance work.
Ship sailed with half ahead only and completed the voyage. At the port we inspected all the units, Turbo charger etc. Everything was normal when ship sailed out from the port again, the same problem occurred . At the outer anchorage, the engines were stopped and chief engineer told to remove the inspection door of the exhaust manifold inspection was carried out. Found part of the bellows got sheared inside. These were falling on the gratings of turbo charger creating the noise. The broken pieces were sufficiently big and were obstructing the passage for the exhaust gas to the turbo changer. This was rectified and inspection door was boxed up. The engines were started and the voyage was resumed, after which there was no noise in the exhaust manifold and no more surging also.