”Sometimes, it is the smallest things that cause the biggest problems,” notes the UK MAIB. In its latest Safety Digest, it references a case in which a 38ft charter angling boat became stranded due to a minor mechanical fault while at sea with eight anglers and a lone skipper aboard, highlighting the lessons learned.
The angling boat was some 800m from shore and in an area prone to fast-running tidal mstreams when the engine stopped. Attempts to get it going again proved unsuccessful and the skipper used very high frequency (VHF) radio to call for assistance. The local Royal National Lifeboat Institution (RNLI) all-weather lifeboat was dispatched and towed the angling boat back into port, where the anglers and their catch were landed ashore. A simple tale with a happy outcome, but certainly one to learn from.
The skipper investigated and found the problem with the engine after many hours of head‑scratching. Within the fuel filter was a ballcheck valve comprised of a buoyant aluminium ball designed to prevent fuel being syphonedback through the fuel system when the engine was switched off. This ball check valve was positioned at the inlet to the fuel filter and so exposed to a flow of fuel that had not yet been cleaned.
The restrictions in the chamber where the buoyant aluminium ball sat had become clogged with debris over time and eventually jammed the ball, stopping the flow of fuel to the engine and causing it to stall.
Lessons Learned
#1 Be Aware
The position of the ball check valve, and the risk of it blocking, was neither obvious nor known to the skipper. A routine change of the filter element following the instructions in the manual did not include a requirement to strip down the check valve. It is important to know the systems and be aware of possible issues. This particular issue, though thankfully rare, is one that many users of such filters know about.
#2 Maintain
The upkeep of equipment should cover all the necessary actions to make sure it remains in good working order. A clean fuel system is vital to the safe operation of an engine and maintenance tasks for all component parts should be identified and carried out on a routine basis to promote reliable operation.
#3 Plan
The skipper in this case made a good decision to call for help before the angling boat got into serious trouble. It is prudent to be aware of the hazards around you, especially when you are reliant on a single piece of machinery for your safety. Operating close to shore in a fast-moving current needs careful consideration when a single failure could leave you in a perilous position.
