My fuel tank is below the cabin sole. Grp and built into the boat. No drain on tank. Pipes are top connected so no leaks. He tanks are structural. Can't say a leak would never happen but vastly reduced riskI'm all in favour of a bilge alarm, but chary about automatic bilge pumps. I used to winter in the Caledonian Canal, and a neighbouring boat developed a leaking fuel tank, so her automatic bilge pump duly pumped about 200 gallons of diesel into the canal.
I had a look at your article. The set up you had is vastly different to mine.
You cannot have too many pumps.
I had no end of trouble with float switches on earlier boats. Debris in bilge can shift and block them - mostly causing them to flatten battery or burnout by never turning off. Or the float switch can move from its fixing and thus rise above sensible sump level.
Inbuilt float switches are no better in my experience. They are still prone to debris and possibly more so as they are effectively in a cage. With a tiny gap between the float and the cage. Anything in there stops the rise and fall of the float. When the float fails you then need to install an external float anyway.
Not familiar with in built floats, both the whale and rule auto bilge pumps use water proximity sensing electronics - presumably just a conductivity check, and the bolt on rule sensor is the same. I imagine an enclosed float is less vulnerable to big debris as cannot get through strainer but trapped in proximity to small debris.
Just mount the pump on a thin section of harwood, prerably teak or mahogony, and then screw the filter section, (My pumps have built in sensors), to the wood, although in many cases the pumps cab belft free standing. Whale and rule are both kind of expensive, and I carry spare pumps.
Never sleep with a generator or main diesel running, as both have fuel returns lines that can fail, as they are a main cause of fuel in the bilges incidents. Wire the blige pumps off switch to its own fuse and and have a different switch for the alarms.
On long passages how do you not sleep without the engine running if there is no wind?
Saying your battery are flat is like saying your diaphragm in your pump has a hole in it. If you only have one pump your snookered. With a sensible set up you have several electric pumps, how would your batteries get flat? You have an engine with alternator. We also have solar, wind, water charging plus a diesel generator. The engine battery is seperate to the house battery so the engine can start if the house batteries are flat. It can charge the house batteries. The generator has it's own battery. It can charge the house bank. Power consumption of electric pumps is really not relevant. In 12v money we have a 120Ah alternator, up to 200 amps charging on the generator. We liveaboard mostly. At least if a leak occurred when we weren't onboard the pumps will run until the solar can't keep up. Not much happening if you have a manual pump, which we do in the form of Henderson mk5 toilet pumps as a last resort.
A Belgian friend of mine was en route from somewhere near Stavanger to Ostend in an identical boat to mine. Single handed. There is not a space for a really large battery bank & the size of boat would not normally warrant it. He went to start the engine to charge the batteries when he realised that he had left the start battery switched to his domestics. He ended up with zero electrics, no nav lights, VHF etc. in a shipping area, at night in zero wind, so his wind steering was useless. He was exhausted.
So he had no back up. Not great seamanship. Why did he have a system that allowed him to make that mistake? Its very simple to have two large illuminated LED battery voltage displays near the companionway steps. One for each bank. You don't make that mistake then. If the voltages stay the same, the batteries are combined. When I sail I isolate the engine battery. The engine battery voltage display goes out. Battery isolated. Systems on boats need to be resilient to the 'what if' scenario. Where there is single point of failure comsideratiotn should be given to a back up of some description. A power-packed and jump leads would have got him out of that situation.
So does he & so do I, but he made a mistake. I have in the past as well, I am sure that I am not the only one, especially those with combined 123 switches. . We both have monitors on our domestic bank, but not the starter battery. We cannot see them from the cockpit. You have to remember these are not live aboard boats with loads of stuff wired up all over the place. Most of the time he does club racing with the RNSYC out of Ostend, with an annual cruise. That is the sort of thing many do with smaller AWBs like ours. They are simply not set up for serious offshore blue water sailing. I doubt that many would contemplate Stavanger to Ostend in one leg SH, as part of a normal trip in a 311 for a holiday between work commitments.
