Air cooled engine vs. sinkings

[wakey_wake]

Mine is water cooled with a skin tank 👍 , so I'm only asking here in an "If I had a boat like that, what would I do?" way.

 

The recent storm raised the water levels here, and a boat has sunk. 😢

I'm not going to say much about that because I suspect there will be disagreements about how it happened. All I know is the water level rose three feet during the night and that boat didn't follow. It looked like a project-in-progress boat and I've never seen its owner.

 

We can't see it just now, but we suspect it had an air cooled engine with the usual big slot in the side just inches above the water line...  so now I'm looking at other air-cooled boats and 😨 wondering "Should I say something? Do they know the risks?".

 

The first air-cooled engine I met had its cooling air intake in the roof, a bit like a giant mushroom vent. I believe it was a DIY conversion from unpowered. The effect is very noisy, and it's a liability when cleaning the roof with a bucket of water. But it does seem like a more sensible place.

 

So what are people's thoughts on moving an air intake from below the gunnels?

 

 

 

Other threads mentioning this include,

 

 

One on mods to hull fittings to raise the freeboard (do I mean freeboard in this context?),

 

[Alan de Enfield]

7 minutes ago, wakey_wake said:

All I know is the water level rose three feet during the night and that boat didn't follow.

 

Without knowing the details and facts of the sinking, but taking your quote at face value my immediate response would be if the owner had learnt to moor properly (using Spring-lines) the boat would have risen with the water level and it would not have sunk.

 

A boat will continue to float with its 'normal freeboard' irrespective of water level, unless it is either 'held down', full of rain water or is leaking.

 

Where I moor against a wall (tidal) we can get as much as 10 feet difference between high and low water (obviously twice a day) just using a bow and stern line is just not an option.

[David Mack]

14 minutes ago, wakey_wake said:

All I know is the water level rose three feet during the night and that boat didn't follow.

Any boat that is tied down firmly is at risk of sinking in those conditions (or of breaking a mooring rope/bollard/tee stud/dolly or whatever else is holding it down and being swept away). Few narrowboats are watertight to 3 feet above the normal water line - water would be coming over the hull sides!

[Mad Harold]

Have seen a few narrowboats with air cooled (usually a Lister) engines, and noticed some have the air intake (I believe they are called jacuzis or something like that) frighteningly close to the waterline.These have been older boats and have probably got heavier with junk stowed aboard or have been overplated.

It would I think be safer to have these air intakes on the cabin side above the gunwale, or perhaps a ship's periscope type air inlet mounted on the aft deck.

[wakey_wake]

8 minutes ago, Alan de Enfield said:

taking your quote at face value my immediate response would be if the owner had learnt to moor properly (using Spring-lines) the boat would have risen with the water level and it would not have sunk.

I'm under the impression that it's more complicated than that. As I said, I've never seen its owner - and I'll leave you to fill in the gaps.

6 minutes ago, Mad Harold said:

It would I think be safer to have these air intakes on the cabin side above the gunwale, or perhaps a ship's periscope type air inlet mounted on the aft deck.

Exactly. I'm watching somebody enthusiastically fitting out a nicely painted boat. It has a Lister-type hole in the side.

[Alan de Enfield]

A boat sank on the Thames, 5 people and a dog onboard.

 

The boat had been overplated which added so much weight that 'unladen' there was only a couple of inches of 'freeboard to the air vents, with 3 people on the rear the air vent became submerged and the boat sank.

 

Beware the risks of overplating rather than re-plating.

 

 

 

 

 

 

21 minutes ago, Mad Harold said:

It would I think be safer to have these air intakes on the cabin side above the gunwale, or perhaps a ship's periscope type air inlet mounted on the aft deck.

 

My Cruiser has a big 'rotating' thing on the cabin roof, the orifice is about 12" diameter (they have them on huge ships so big you can slide down inside them) these are piped down into the engine room to provide air, It can be rotated so when the water is rough you don't get a lot of spray down them.

 

 

Edited November 4, 2023 by Alan de Enfield

[dmr]

Its not only air cooled engine boats, I have seen quite a few boats, including very recent newbuilds, that have slots in the side to supply air to what is almost certainly a water cooled engine (or generator).

[Arthur Marshall]

Mine's air cooled - this is the  hole the hot air comes out of - on the other side at about the same height and size is the air intake hole. That's on a boat with two sides and three bottoms, so it's well above the water level still. The gas locker and front deck drain holes are a lot nearer the water, and while they can get a bit of water in if there's a LOT of turbulence while filling a lock, say, but what goes in comes straight out again.

[Momac]

If you tie up a narrow boat too tight to a fixed object and the water rises 3 feet there is every chance it will sink regardless of the air or water cooled.

[Peanut]

3 hours ago, dmr said:

Its not only air cooled engine boats, I have seen quite a few boats, including very recent newbuilds, that have slots in the side to supply air to what is almost certainly a water cooled engine (or generator).

Yes, I have seen these large vents in recent Collingwood boats, which are definitely water cooled.

[wakey_wake]

1 hour ago, MartynG said:

If you tie up a narrow boat too tight to a fixed object and the water rises 3 feet there is every chance it will sink regardless of the air or water cooled.

 

Um yes.

 

Well I feel a little guilty for not predicting the problem after the heavy rain, or seeing the problem happening; and preventing it as a neighbour should. However in my defence...

 

The heavy rain showed me some small leaks and I was busy with the dehumidifier. Then the actual rise happened some time in the small hours, and I was not rolled out of my bunk. First I knew about it was when I opened the curtains and discovered that, even with wellies, I was not going ashore dry.

 

For me the important messages are

to leave my lines long, especially if I'm going away. I was already doing that although I'm sure there is more banging around when its windy.

to remember that waters will rise after remarkable rain. Last time it happened here, I was away.

maybe to have phone numbers for the neighbours? I still don't.

[Momac]

16 minutes ago, wakey_wake said:

 

Um yes.

 

Well I feel a little guilty for not predicting the problem after the heavy rain, or seeing the problem happening; and preventing it as a neighbour should. However in my defence...

 

The heavy rain showed me some small leaks and I was busy with the dehumidifier. Then the actual rise happened some time in the small hours, and I was not rolled out of my bunk. First I knew about it was when I opened the curtains and discovered that, even with wellies, I was not going ashore dry.

The sunken boat is not your responsibility. 

[Alan de Enfield]

32 minutes ago, wakey_wake said:

For me the important messages are

to leave my lines long, especially if I'm going away. I was already doing that although I'm sure there is more banging around when its windy.

 

You can get other problems if you just leave long lines - learn how to moor correctly and use Springs, they will take up the vertical change whilst the bow and stern lines will keep you against the wall / pontoon / bank.

[magnetman]

My first narrow was a 30ft Hancock and Lane with a Lister SR2. On its original hull so was floating at the correct height. I did a lot of boating in it including through winters and there were times when I would have quite liked a bit of warm air wafted up under the recaro seat I had mounted on a beer keg for steering. If the air from the engine could have been ducted up rather than sideways it might have made the boat safer and warmed the seat. 

 

Having said that the cooling air stinks and carries atomised oil so it would have been dirty and noisy. 

 

Don't really like air cooled engines. 

 

People do need to tie their boats up properly. 

 

 

 

[Naughty Cal]

10 minutes ago, Alan de Enfield said:

 

You can get other problems if you just leave long lines - learn how to moor correctly and use Springs, they will take up the vertical change whilst the bow and stern lines will keep you against the wall / pontoon / bank.

You forget very few people actually know how to moor a boat up safely 🙄

 

Even some who claim to be "seasoned" boaters.

Edited November 4, 2023 by Naughty Cal

[magnetman]

47 minutes ago, Peanut said:

Yes, I have seen these large vents in recent Collingwood boats, which are definitely water cooled.

 

I saw them on a wide bean the other day going out of Limehouse on the biggest tide for a long time. They were locked UP out of Limehouse not down. It was mighty rough even the French warship which went past was rolling. 

 

The hired skipper had taped over the vent holes with aluminium tape and left a deck board open. 

 

Hazardous as there were the owners aboard as well. 

 

I expect fun was had by all. 

 

 

[MtB]

6 hours ago, wakey_wake said:

Mine is water cooled with a skin tank 👍 , so I'm only asking here in an "If I had a boat like that, what would I do?" way.

 

Look after it and not stupidly let it sink.

 

Simples, to coin a phrase. That's what I'd do anyway.

 

Hope that helps  

 

 

 

Edited November 4, 2023 by MtB
Add a bit.

[wakey_wake]

34 minutes ago, MtB said:

Look after it and not stupidly let it sink.

 

Aye-aye skipper. Or do I mean aye yai yai?

 

Sometimes "not stupidly letting" means looking at a thing and deciding to make changes. Like the 12V feed to the bow radio.

Why doesn't it switch the radio off when I flip all the breakers? 😨

So it turns out there is a 4mm² wire running the 2x50ft for this, and the fuse is by the radio. If that got shorted just before the fuse then it's going to pass about 100A... not enough current to instantly destroy the cable, and the battery won't enjoy it... but it'll hold up for a good few minutes. Meanwhile that 1kW will be dissipated among the woodwork under the gunnels, the whole length of the boat.

 

Most of what the previous owners did here was top class with the best available at the time. Except this 12V feed, which was waiting to be a boat igniter.

 

It now has a fuse right by the battery. The 12V system needs some other re-working but it's better than it was.

 

 

2 hours ago, Alan de Enfield said:

You can get other problems if you just leave long lines - learn how to moor correctly and use Springs, they will take up the vertical change whilst the bow and stern lines will keep you against the wall / pontoon / bank.

 

I am seasoned, but prefer mustard to chili. Some days I think I've done my research and know what I'm doing. Other days I doubt.

 

I don't run four long ropes because the inside ones would be a trip hazard and destroyers of paintwork. I have no fairleads, just two dollies on the trad stern, a T-bar at the bow and a couple of painters (used only when I'm watching them).

I've been using two lines out fore & aft, at maybe 20° or 2~3 meters to the bollard. It can't go far fore & aft and there is plenty of potential vertical travel.

The main problem with leaving the lines long is the boat rattles port to starboard which causes bumping when it's windy.

 

My biggest worry here is if the water comes up more than 4ft then there is a risk of getting hung up on the quay heading. That's another reason not to be tight against the side.

[blackrose]

12 hours ago, Alan de Enfield said:

A boat will continue to float with its 'normal freeboard' irrespective of water level, unless it is either 'held down', full of rain water or is leaking.

 

Exactly, so there is little correlation between boats with air cooled engines and sinkings.

 

The fact that the boat described in on the OP's post had air vents to close to the waterline may be a factor, however as the water level rose 3ft almost any boat held down and not able to float may have sunk including those with water cooled engines with vents say 2ft above the waterline.

 

So the OP's air cooled engine vs sinkings line of thinking is a red herring.

Edited November 5, 2023 by blackrose

[Alan de Enfield]

9 hours ago, wakey_wake said:

I don't run four long ropes because the inside ones would be a trip hazard and destroyers of paintwork. I have no fairleads, just two dollies on the trad stern, a T-bar at the bow

 

You don't need 4 long lines, with a NB your breast lines should be short and come off the boat at (around) 90 degrees. The spring lines from the bow go as far 'sternwards' as possible before chafing the cabin side/corner. The spring line from the stern (Dolly) goes as far 'forwards' as possible and on occasion may even use the same bollard / stake as the line from the bow - but it depends on your boat shape. You have your bow & stern lines out at roughly 45 degrees.

 

It is not an exact science but spring lines can be adapted for use on a NB, if you do not have, or want to fit a cleat. You do not always need to use a head & stern line (I dont when leaving the boat for the Winter) Springs and Breasts are sufficient for most situations.

 

 

Of course, if you are spending time on waters likely to have varying 'heights' then it make sense to add cleats onto the bow just forward of the cabin, I know several forum members have done this.

 

This is the ideal (and typical) springs set up but is not always possible with a NB

 

 

 

Sprng "3" is often possible on a NB, but spring "2" will tend to chafe on the cabin edge . Note line "4" is attached to the offside dolly/cleat

Edited November 5, 2023 by Alan de Enfield

[magnetman]

1 hour ago, Alan de Enfield said:

 

 

 

 

 

 

 

That looks like a floating pontoon to me.

I would want the bow and starn lines to have much more angle ie the connecting points to the bankside to be much further from the boat to allow for rise and fall. 

 

 

[Alan de Enfield]

1 hour ago, magnetman said:

I would want the bow and starn lines to have much more angle ie the connecting points to the bankside to be much further from the boat to allow for rise and fall. 

 

That is the common mistake - the bow lines dont take up the rise and fall, that is done by the springs. The bow and stern lines are simply to keep th boat close in to the side / wall / pontoon, and, as I have said can be easily replaced by the breasts for normal use. I only put all 6 lines out if leaving the boat for months at a time.

[ditchcrawler]

3 minutes ago, Alan de Enfield said:

 

That is the common mistake - the bow lines dont take up the rise and fall, that is done by the springs. The bow and stern lines are simply to keep th boat close in to the side / wall / pontoon, and, as I have said can be easily replaced by the breasts for normal use. I only put all 6 lines out if leaving the boat for months at a time.

Surly the breast lines if tight enough to hold the boat against the bank must limit the rise and fall. If you look at the fishing boats moored in Gt Yarmouth, at high tide the stern rope will be laying in a U shape in the water, at low tide both bow and stern will be just less than tight

[magnetman]

My boat which is moored on the Thames where the level can change by up to 4 feet or 5 in extremis and the flow is very fast has bow and starn lines with much more angle. If I tied them like in that picture and the River came up 3 feet the boat would heel over. 

 

I've got a total of 6 lines out and a security chain. The main load is taken by a 4mm dia prestretched nylon line (recoil starter rope) thats for a 16 tonne boat then there is a 10mm then there is a 12mm rope. 

 

If the load gets up the little rope will part and this when one checks everything is alright. 

 

This is on a derelict country estate pleasure garden so there is no hardware just various trees. 

 

Worked all last winter. I do have a scaffold pole hammered into riverbed which helps stop boat riding over the side. 

 

 

 

 

[alan_fincher]

2 minutes ago, ditchcrawler said:

Surly the breast lines if tight enough to hold the boat against the bank must limit the rise and fall.

 

Yes they must, I agree.