Inability to keep the water out > Long distance rescue

[mischief]

It's been noted but some seem to be overlooking the real situation.
That is; it takes a relatively small breach to quickly overwhelm what most would consider more than adequate means of dealing with an ingress.

Many boats I suspect have been needlessly lost because of simply being ill prepared for reality. I know several boats around here that have needlessly sunk because of simple fixable ingress issues. However there was no way to fend off the water and make a fix in time with what they had available.

Having; redundant, simple and effective means of pumping a high enough volume of water to save the boat, should a relatively repairable breach occur plus a plan to carry it out is key.

Again an underestimate of how much flow rate a certain size hole can produce is normally woefully underestimated. Combine that with an overestimation on what their bilge pumps can cope with or how fast they can bail with a bucket for, leads to a failed situation.

Some must also envision the boat upright and in calm weather when it happens. The water line while healing, pitching, listing or whatever radically changes and your safety margins will be significantly reduced. Waves may increasingly become easier to wash into the cockpit.

Sure a scared man with a bucket can bail fast. How well is that going to work while you are down below trying to clear the water out the companion way over the cockpit sides? Or do you wait for the water to be high enough you can reach in from the cockpit into the cabin and bail from there? How are you supposed to carry out simple fixes when you have to man the manual bilge pump or bail?

I for one am setting up the boat with a mind one person can deal with most reasonable situations. If I have more crew that's a bonus if not then I am not at a total loss for reasonable situations.

Sure if I get a gaping hole that likely would mot be fixable at sea anyway then the boat will be gone.

FYI I have both had to use manual high flow bilge pumps and buckets in real world situations and speak from first hand knowledge on how well they work. I definitely keep both and highly value their importance. I do not though believe they are enough to save a boat from some otherwise easily managed situation.

I think it's about a balance and personally being able to live or die by the choices you make and anyone else that your decisions have effected.

Think about how much displacement you can afford to safely loose and in what conditions. Calculate the amount of ingress before you would know there is a problem, minus that amount. Figure how much water you can evacuate from the vessel while searching for the source. Then calculate the time to fix a certain problem and calculate the influent rate for that issue and see if you have enough time. Is there contingency factors built into your calculations? What if you have one source and it fails? What scenarios do you feel are worthy of prepping for? At some point you may not be willing to sacrifice money, resources etc to handle more because the risk is insufficient. Everyone will mitigate the risks different and that is their choice.

I personally am loving the idea of incorporating the OB for pumping and hope something comes of this. Brainstorming is excellent and just because someone thinks its not possible does not mean it is or that it can't inspire an idea that is. (Not talking about the OB angle either just a general comment)

The idea behind this post is to just keep people thinking about problem more thoroughly.

Now these are only my take on things and may not be worth the time it took to read.

Cheers

[goboatingnow]

Originally Posted by bornyesterday

@goboatingnow

Yep, deepest, darkest locker I possess, buried under a ton of stuff and on top of the liferaft.
Unused and untested for a couple of years at least, hoses at the other end of the boat, crushed by more stuff, oh bugger where's the diesel.

"After all I was the first one to suggest it as my simple solution." Oh that must be where I got the idea from... hope I remembered to say "Thanks?"

Someone let me know if I start posting contradictory opinions in the same thread please?

Jeezus.

I was meerly referring to this thread, not all commentary about crash pumps .

I'm in the RNLI. We have a lot of experience with such pumps. It's a solution to a point , when you find you really need them. It's usually too late.

Dave


Sent from my iPad using Tapatalk

[roverhi]

Mahalo for posting the Yachting Monthly tests. Gives me a couple of ways to go in preventing sinking. Anything but a huge engine driven pump is useless with a serious breach. Stopping or seriously reducing the inflow is the only to way stop a boat from sinking.

Originally Posted by capt-couillon

Interesting article about some real world tests on keeping the water out,
(http://www.admiralyacht.com/admiral-...at-sinking.pdf)
They bashed an approximately 3" hole 8" below the water line in the forward part of the boat. Then put her in slings and lowered her into the water to test various methods to "keep the water out".

Here is a couple of vids for the same tests
Yachting Monthly's Crash Test Boat is holed Part 1 - YouTube
Yachting Monthly's Crash Test Boat is holed Part 2 - YouTube

[capt-couillon]

A couple of personal comments and a first person case study of emergency leak repair..

Always wanted a "crash-pump" but never had the room or money (needed for more pressing needs like sail repairs etc). I will not sail however without 2 manual pumps. One below deck, and one in the cockpit. At 45 strokes per minute, they will move enough water to keep up with a temp repair that still leaks. Every time the water gets to the cabin sole, man the pump for 10 minutes and there you go.

Leak volume...
Inflow calculations are complicated, but rule of thumb, and observations in the article I noted earlier in the thread predict an inflow rate for a 3" hole 8" below the waterline at about 70 gal/min. (4000 lbs in 7-8 minutes) Unless you can get a high volume pump in place and operational in under 15 minutes it would seem to me that leak location and temp interior patch would be best approach.

Leak location...
A collision with an object large enough to hole a modern hull should be noticeable (to say the least) If this happens offshore, the most likely point of impact will be forward on the lee side of the vessel (The reason for this is an exercise left to the mariner) If a collision has not been observed, most likely point of ingress is via existing hole (thru-hull failure, shaft alley, rudder tube) Of course, a prudent mariner has previously provided adequate access to all possible ingress points and has appropriate wooden bungs available. (mine are tied to the corresponding thru-hull with a marline lanyard).

Removal of casework/bulkheads for access to collision damage...
A 4lb short handled sledge (an American screwdriver) is a most effective tool for removal of stationary objects in a timely manner.

A personal experience in dealing with an "emegency" leak repair. (Location, Colon Panama 1991)...

Unexpected sea conditions approximately 100 miles NW of Colon caused the autopilot tiller to part ways with rudder quadrant (poor design on my part). The decision was made to return to Colon to affect repairs rather than continue to Isla Providencia as we had access to better facilities in Panama to repair/re-enforce the tiller attachment. Tied up stern to at the (now-defunct) PanCanal yacht club seawall. Rudder was lowered out of the upper bearing and suspended in the rudder tube to allow removal of rudder quadrant while vessel was in the water as railway access (and cost) was limited. After repair in Panama City, preparations were made to reinstall the quadrant and lift the semi buoyant rudder back into place (still in the water at the sea-wall, 10' depth).

This necessitated myself to get under the hull and lift the rudder up through the upper bearing. The combination of leverage (4' rudder + 3' shaft, no lower skeg) and vigorous movement of the rudder while attempting to move the shaft up through the lower bushing revealed a previously undiscovered dry lamination in the rudder post to hull joint.
Said dry lamination resulted in total failure of the rudder tube to hull joint, with accompanying inflow of copious amounts of water (3 1/2" rudder tube) and major consternation of crew member inside the hull (I could hear him yelling through the hull while underwater) .

Immediate actions involved jamming available materials (Man... those were my "good" tee-shirts) into the space between the rudder shaft and hull with a screwdriver and a hammer, starting the 4000gph "disaster" pump and the engine. The engine was rigged with an aux raw water intake attached to a strum box in the bilge, but it was not needed. Primary reason to start engine was to make sure the house bank kept up with the high vol pump draw.

After the initial panic, another trip over the side to jamb more rags (my "offshore" tee shirts) between the rudder stock and lower hull bushing, the standard (500gph) bilge pump allowed us the 3 hrs required to arrange a haul out on the railway.

Admittedly this happened while tied up in port, and only 10' of water, but she could have sunk just as well (how embarrassing is that?) But getting the inflow slowed to a manageable level took all of 5 minutes and the was never more than 1 inch over the sole. (It needed a good scrub anyway).

Interesting to note my first reaction was to plug the hole before starting the pumps and engine.

[minaret]

Why do people assume that because you want a crash pump, you don't already own a fothering sail?

[Cheechako]

Originally Posted by Andrew Troup

Hmmmm ..... I thought KISS stood for simple. I'm not sure an exploded parts diagram of that pump would mark it down as being from the simple end of the spectrum of contenders; I'd have thought that was reserved for buckets, and Edsons...


But I guess you could point out that an exploded view of a human makes a Honda pump look simple. And buckets and Edsons don't work without a prime mover.

To which (scratching head and conceding the point for a moment)

Ah.... yer: but the human was there anyway, and so is the diesel prime mover (and for those who like'em, the outboard)

Isn't it better to use resources which are already to hand, if you can?

Yeah, I hear you. Whatever size pump you have or get, there is a potential for a leak larger than the pump. I think for a small boat ( I call that up to 45 ft) This is a good concept. What I like about this is it pumps alot more than you can do with a manual pump or bucket, (80 -55gal drums an hour!) is totally independent from the the other boat systems, is very small to store and as Minaret pointed out, leaves you to be able to fix the leak while pumping. Especially for short crew or singlehanders, there's no way you can bail much with a bucket.
Sure a 3" trash pump is great but you have to have room for it. If your small boat is leaking more than 80 55 gal drums an hour, you'd best be preparing the liferaft and escape bag....

[Panope]

Get the Honda pump that Cheechako suggested or get an Alten D.C. generator (or get both). Both units use the same engine so you could buy one and some of the components of the other to kill two birds with one stone (engine). Never start engine. Never add fuel. Store in dry bag.

Now for the crazy brainstorming part:

Get a large diameter (12 inches?) v-belt pulley that can be attached to the crankshaft of the boat main engine. Get a small diameter (2 inches?) v-belt pulley that can be attached to the crankshaft of the Honda after removing pump (or generator).

Fabricate a pivoting mount that will place the Honda so that the v-belt pulleys are in alignment. Start Honda while belt is loose. Have lever to be able to tighten the belt to start main engine. Belt will smoke and be generally pissed off but this contraption only has to work once.

So in theory, you could have one (20 lb.) engine that could perform three tasks.

Steve

[Andrew Troup]

Originally Posted by capt-couillon

A couple of personal comments and a first person case study of emergency leak repair..

.....

Interesting to note my first reaction was to plug the hole before starting the pumps and engine.

Lots of great stuff, much food for thought, and very useful war story, thanks!

The question of 'to pump first or plug' seems easy to answer at the two extremes. If you know the source (as you did), it's hard to think why you wouldn't plug first, but I guess there might be situations where ANY sort of effective staunching would require some setup time.

And it might seem a no-brainer that if you DON'T know the source, you would activate pumps of capacity appropriate to the influx rate before going looking.

But again, it seems to me circumstances always alter cases: if it was a collision situation, in a boat with easily viewed hull interior in the likely zone, I'm thinking I'd take a quick look so that my brain could be triaging the situation for as long as possible, and based on what I saw I would hope to have some basis for 'to pump first or plug'...

It seems to me that a lot of boats are abandoned because of CHRONIC leaks, rather than acute ones. Chronic leaks can wear down the equipment, placing increasing physical demands on the crew, and perhaps most of all impose dangerous psychological and motivational challenges.

A bit of bilgewater, when distributed in rough weather, can tip a boat from feeling like a safe haven to feeling like hell on earth. It's not just the effect on equipment and provisions (and things like books and charts and toilet paper), it's the invasion of personal space.

I detest having to sleep in wet bedding, personally, and it's one of the few things I find totally demoralising at sea.

Some chronic leaks are tricky. Hull-deck joins, badly done, can be impossible to keep dry at sea, because the water will travel longitudinally within the join and come out elsewhere, even if you've managed to get a "sticking plaster" style superficial poultice to stick in places where you do have good access ... and if the entire perimeter is leaking just a dribble, it can still realy add up in bad weather.

One or two dodgy welds at the root of a skeg on a metal boat can be virtually impossible to mitigate en route, but might not require a great deal of pumping per day (at first, that is; naturally it will get steadily worse, and that too can be psychologically tough)

For post-leak peace of mind, I think it's important on long voyages to have options: if all the pumps rely on one resource, that resource can either be inoperable or simply run out.

As a last resort, manual pumps (for chronic, rather than acute leaks) will generally run as long as the diaphragm, handle, check valve and food do.

[goboatingnow]

I detest having to sleep in wet bedding, personally, and it's one of the few things I find totally demoralising at sea.

It's seems we have one thing in common, I agree completely

Dave


Sent from my iPad using Tapatalk

[Andrew Troup]

I'm still processing your last wild idea, Steve, about the bungees to start a diesel.

I have to confess an aversion to conventional bungee cord in marine contexts, partly because a co-conspirator of mine is even more partial to them than you, and I ended up maintaining his boat for a number of years (in a win-win situation, where I got to use it!)

And I'm one of those people who can't stand jobs which don't stay done, like mowing lawns .... and replacing bungee cords in hostile environments ....

For a while, someone here downunder was making synthetic solid bungee cord (and a bunch of smart end fittings, which locked on with snap-fit collets, a bit like nylon pneumatic tubing uses)

I replaced some of the bungees on this sailboat, and they're still in perfect nick a decade later. Unfortunately the manufacturer seems to have vanished, perhaps because it was obviously not as cheap as the traditional rag and rubber stuff... and kiwis still tend to have a pioneering culture approach to paying for durability.

Inspired by your idea, I thought I'd try and restock, and yesterday I paid a visit to a very friendly canvas goods and awning maker, who had some old stock he let me have for $1 a m!

- - -

So an even wilder idea I had was to use multiple strands of bungee, or nylon rope, disposed along the axis of the crank (perhaps with the Honda lashed to the base of the mast, like Ulysses!) to connect your proposed donkey engine to the prime mover, in the manner of a rubber band on a model aeroplane.

That way the Honda could store energy in the bundle (perhaps with the prop shaft brake on, and the prime mover in gear) for a single climactic release (sorry if that sounds vaguely X rated) by shifting to neutral from a safe pozzie crouched in the cockpit, when the bundle was visibly at the point of rupture.

But obviously the axial forces trying to pull the engines together would be pretty scary (not to mention the rotary forces adding to the tensions in the lashings to the mast) and I couldn't think of a good way to disconnect the bundle, if and when the prime mover did fire, short of a pre-rigged guillotine close to the prime mover, fired from a safe distance. It all seemed wildly impractical ... but an interesting thought experiment all the same.

[Terra Nova]

If all you want is an alternative starting method for an auxiliary for which no hand start is available, how about replacing the dink's outboard prop with a pulley and belt drive from a spare front engine pulley?

[Andrew Troup]

Originally Posted by Terra Nova

If all you want is an alternative starting method for an auxiliary for which no hand start is available, how about replacing the dink's outboard prop with a pulley and belt drive from a spare front engine pulley?

This may be a workable idea. I don't think it's a foregone conclusion, however, that a V belt, used as a slipping clutch, will transfer enough torque to the crankshaft to start any diesel other than the smallest, particularly one without decompressors / valve lifters.

However if a pulley was instead fitted to the camshaft (which could be feasible say on a Yanmar 2 or 3GM) this would double the torque, and provide better speed matching.

(The handstart on the 1GM and 2GM is via the camshaft)

I've used slipping V belts in lieu of a clutch on small machine tools, notably lathes, and there's a fairly low ceiling on the torque they can provide when there's a significant speed delta, eg a 'standing start' situation.

Furthermore the small pulley, on the outboard, might simply not have enough surface area in contact with the belt to do provide anything more useful than frictional heating. If the pulley diameter is increased, it will be trying to crank the motor ridiculously fast, given that small outboards need to run at two to three times the speed of a small diesel to develop usable amounts of torque.

However, it may be that the high cranking speed achievable with a sensible ratio could be used in conjunction with "blocked air intake" jury decompression, to achieve a 'momentum' start, like 'bump' starting a car.

In the present context, this implies spinning the engine rather fast, then recompressing all cylinders simultaneously by removing the obstruction.

There are two ways of increasing the storage capacity for (angular) momentum:

1) a heavier, and/or larger diameter flywheel (absent in modern engines)

2) spinning it faster (which the ingenious adaptation of an outboard motor, per Terra Nova's interesting proposal, might permit)

A fringe benefit: prolonged and energetic spinning of the engine, partially decompressed in this ad-hoc way, might achieve a useful degree of pre-warming of the block and the oil.

It would pay to have the stop lever pulled, to prevent excess diesel washing the walls of the bores during the preheating phase.

Push it back in before recompressing.

Energetic preheating could be particularly useful if the engine is no longer in good condition, and/or has certain forms of indirect injection but no glowplugs (like most Yanmars), and/or when sailing in very cold waters.

[bornyesterday]

Originally Posted by Terra Nova

If all you want is an alternative starting method for an auxiliary for which no hand start is available, how about replacing the dink's outboard prop with a pulley and belt drive from a spare front engine pulley?

If the outboard's not fixed to the engine then the belt will pull on the engine mountings - which could be catastrophic.

Curious about the Yanmar camshaft suggestion too. Presumably if "the handstart on the 1GM and 2GM is via the camshaft" there are reduction gears?
I don't know the Yanmars but I haven't met a 4-stroke where the camshafts didn't run at 1/2X engine speed rather than 2X?

[Rustic Charm]

All these ideas are interesting readying and it's great to brain storm. But I think some, even many are getting a little far fetched.

The simplest way to start an inboard diesel when the batteries have died, or water ingression (after the water has been reduced), is to get a portable starter pack. These are less than $100 and pack a punch that would give you one or two attempts at starting it, maybe more. You just have to remember to keep it charged.

[capt-couillon]

It seems to me that a lot of boats are abandoned because of CHRONIC leaks, rather than acute ones.

Excellent point... and (as usual) I have an unrequested opinion.

Let me say in advance, I understand the purpose of an "automatic" bilge pump. Especially for those who do not live aboard their vessel. My float switch is connected to a LOUD alarm rather than to a pump. Chronic leaks can fail to catastrophic proportions if not located and evaluated.

I don't mean that classic over the bunk drip, I mean the leaking thru-hull hose, failed packing gland on the engine shaft, etc.... Now I am fortunate enough to have a dry boat. If I have water in the bilge, I have a problem. Unless I were to notice the auto-pump cycling on at random times, how would I know I am shipping water from a small (for now) chronic leak? Wet socks getting out of the rack is a damn good clue. Hopefully I am a little more dedicated to eyeballing the bilge as a full time live aboard... but
it happens.

Two inches above wet sock level the "Grand Theft Auto" alarm goes off, and even if I am not around someone is gonna investigate (What the hell is that?) Any substantial leak is gonna overwhelm my little 500 gph normal pump any way.

Anyway, just food for thought.