14th Mar. 05
After joining a vessel and on first trying out the emergency fire pump I found the engine not cranking by hand by keeping the decompression lever on. Found the piston jammed inside the cylinder.
The engine was completely dismantled, piston removed from cylinder and on inspection found rust formation had jammed the piston rings on their piston grooves and also the piston had seized on the cylinder surface due to the rust.
The formation of rust was attributable to the ingress of water into the combustion space. It was an air engine with cooling fins on the cylinder outer surface. Water ingress into the combustion space might have occurred because the decompression lever may have been kept on after the engine has been tried out and water then entered through the exhaust pipe.
On inspection found the elbow bend part corroded and partly eaten away. A new exhaust pipe with new bend was fabricated in place, engine completely overhauled, replacing new piston rings.
Emergency fire pump tried out satisfied. Proper starting & stopping procedures written on the board hung near the emergency fire pump to prevent recurrence.