SEIZED FIRE PUMP
26th Jan. 04
After signing on a vessel and on first trying out the emergency fire pump I found the engine not cranking by hand despite keeping the decompression lever on.
After the crankcase inspection was done, we found the piston to be jammed inside the cylinder.
The engine was completely dismantled, piston removed from cylinder and on inspection found that rust formation had occurred which had jammed the piston rings on their piston grooves and also the piston had seized on the cylinder liner surface due to the rust.
The formation of rust was attributed to the ingress of water into the combustion space. It was an air-cooled engine with cooling fins on the cylinder outer surface. It was taken into consideration that water ingress into the combustion space might have occurred, because the decompression lever might have been kept on after the engine had been tried out last, and water may have entered through the exhaust pipe while deck washing was being carried out.
On inspection of the exhaust pipe we found the elbow-bend part was corroded and partly eaten away. New exhaust pipe with new bend was fabricated and fitted in place, engine completely overhauled by replacing piston rings.
Emergency fire pump was tried out satisfactorily. Proper starting/ stopping procedures written on a board; same hung near the emergency fire p/p to prevent such a recurrence.