CRACKED EXHAUST VALUE
The ship was a UMS class vessel with B & W main engine. During sailing an alarm in the night indicated that the turbo charger was surging.
On entering the E/R, a heavy metallic hammering noise was noticed from the main engine. M.E was stopped immediately and the alarm for deviation of exhaust temp in # 3 was acknowledged.
Found #3 Exh. valve cracked and a part of the valve broken. The broken piece fell in to the liner space and was hammering the internal area. The compression pressure dropped and the fuel could not be combusted fully. The T/C surged and the Exh.temp deviation alarm became actuated.
Luckily the M.E was stopped in time and saved from severe damage. The chisel marks on the liner, piston and the cylinder head were dressed up smoothly. Small broken pieces stuck up in the Exh trunking grid were cleared.
The damaged Exh.Valve was replaced.