Boat Leaking – The Best Ways to Plug a Broken Through Hull from Yachting Monthly

In association with Admiral Boat Insurance, Yachting Monthly created a series of potential disasters to find out if all the theories of how to deal with such situations actually work in practice. The boat used in the crash test is Admiral’s own 1982 Jeanneau Sun Fizz ketch, Fizzical.

Boat Leaking - The Best Ways to Plug a Broken Through Hull from Yachting Monthly

What happens when your boat through hull fittings fail and you start Sinking? Whether it’s a seacock or a log transducer that fails what can you use to stop the boat leak? The Yachting Monthly team decided to find out what works and what doesn’t.

Holes below the waterline are essential for plumbing, propulsion and engine cooling systems but intuitively they are not a good idea. There are three common ways a boat seacock can fail. A corroded pipe can shear at the boat hull, leaving nothing more than a hole. A ball value can crack leaving just the through hull fitting. Or finally the hose slips off the tail pipe inboard of the ball value but the ball valve is jammed and can’t be closed.

The best ways the team suggested to fix them included a softwood bung, a Forespar TruPlug (which looks a bit like a traffic cone), or a playdough-type mouldable polymer, called Stay Afloat which is possibly best because it can mould into any shape that the hole happens to be. More imaginative solutions included a towel, and a carrot or potato! Whatever is to hand the quickest is often the best to use initially! Lessons learnt include the proper maintenance and checking of the boat seacocks, and using a bit of team work to get someone to man the bilge pumps as soon as water appears while checking all the boat seacocks starting with the largest to see which has failed.

Boat Leaking Video from Yachting Monthly Boat Crash Test

A Series of Crash Tests

Over nine months Yachting Monthly subjected the Crash Test Boat to a punishing programme of destructive experiments, including the following:

  • Capsize
    YM capsized the Crash Test Boat twice to see if the saloon, galley etc could be made safe or become a hell-hole in the unlikely event of a capsize or knockdown.
  • Dismasting
    After breaking the mast under sail, methods of getting rid of the broken spar were tested before it threatened to puncture the hull, then a jury rig was made with what was left.
  • Holed below the waterline
    There’s a thud and the boat groans before sailing on. Within moments the cabin sole is afloat and you’ve got a big problem. YM found out how long it takes to locate the hole and which emergency fixes work best.
  • Galley and engine fires
    YM tested a variety of measures aimed at making sure you can extinguish a fire before you have to abandon ship.
  • Gas explosion
    When did you last inspect your gas pipes and hoses? YM found out how much gas makes how big a bang and exactly what it can do to you and your boat.

Robert Holbrook, MD Admiral Marine

Robert Holbrook“Often, the first natural human instinct when an emergency or disaster strikes is panic. In a series of controlled experiments, the Yachting Monthly crew put theory to the test by re-enacting some typical worst-case scenario sailing accidents or emergencies – such as grounding, capsize and mast failure. Risk assessment and careful consultation with experts was at the core of all tests. How often are incidents like this photographed and filmed in detail? By sharing their findings in a series of articles, I could see how yachtsmen could learn much invaluable information. Admiral bought Fizzical in November 2010 and the project was born. Why not learn from our mistakes by following her story so you can avoid making your own?”

All Yacht Monthly articles are available in full

Download the full, unabridged Yachting Monthly articles in PDF format below for reading at your leisure.

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