low stern

[Naughty Cal]

Insulation!!!!

I'm fairly sure he already knows that.

[Alan Saunders]

Why would wrapping a towel round it keep the cold off ??

 

Don't really get that, or is it a heated towel

 

Insulation!!!!

Yes, but it also insulates from daytime warmth!

 

In a house, insulating cold water pipes may be effective if they are in constant use and the water main is buried three feet (1m) below ground where frost rarely penetrates in England.

[ditchcrawler]

Before you leave the boat tonight block the pump outlet hole with something . . . a cork, wooden bung even a bit of tightly screwed up rag if you got nothing else to hand, just get something in it. If your'e already elsewhere by the time you see this, I'd say go back and see to it right now. Then as soon as possible alter the run of the outlet pipe as suggested by John V and others.

Alternatively, if possible lift the pipe or pump or both up above the outlet level and tie it or fix it any way possible at that level.

Surely the bilge pump needs to be as low as possible in the boat.

Before you leave the boat tonight block the pump outlet hole with something . . . a cork, wooden bung even a bit of tightly screwed up rag if you got nothing else to hand, just get something in it. If your'e already elsewhere by the time you see this, I'd say go back and see to it right now. Then as soon as possible alter the run of the outlet pipe as suggested by John V and others.

Alternatively, if possible lift the pipe or pump or both up above the outlet level and tie it or fix it any way possible at that level.

And if your stern gland leaks you can't pump the water out

[magnetman]

I'm fairly sure he already knows that.

 

Yes I think I understand how insulation works. but I thought it was to keep something warm (or cold) which was already warm (or cold) and being subjected to some sort of heating (or cooling). Lagging an outdoor pipe is to reduce the chance of freezing from wind chill effect as far as I can make out.

 

So, you put a water pump in a boat (no air movement indoors so no wind chill effect). No heating on the boat. If it gets cold enough then surely it will freeze whether or not you wrap a towel round it, unless the towel is in some way heated externally it will get cold like everything else. The wrapping of the towel may delay the freezing if the towel is warm when wrapped around but in the end it will get as cold as everything else and the water pump will freeze.

 

I have been known to fundamentally misunderstand simple physics while understanding the more complex things so maybe I'm being very dim.

[Tony Dunkley]

Surely the bilge pump needs to be as low as possible in the boat.

And if your stern gland leaks you can't pump the water out

In normal circumstances, yes, of course it does, but the OP stated the pump outlet in the hull to be as little as one and a half inches above the waterline. Bunging up the outlet or raising the pump and/or its' pipe as high as possible was suggested as a temporary precaution until the pump installation is altered to eliminate the risk of sinking his boat by having water getting in through the bilge pump outlet. Would you want to leave your boat unattended with what effectively amounts to one and a half inches of freeboard ?

Stern glands don't tend to start leaking when standing without the tailshaft turning, but in any case a dribble from that would be rather preferable to water running in through a hole the size of a typical bilge pump outlet.

 

Nb. Submersible bilge pumps can, and have been the cause of some sinkings due to the lack of any sort of non-return valve in the outlet. I know of one partial sinking that occurred after an owner bought himself one and put it in with a temporary pipe poked out through a hull opening well above the waterline. The pipe was a bit too long for the job and was just dipping a little way into the water outside. This wasn't a problem until he pumped out the rainwater that had got in, switched off everything and went home. Why ? . . . because with the end of the pipe in the water outside and the pump down low in the boat, he had inadvertently set up and primed a siphon.

Edited December 3, 2014 by Tony Dunkley

[Proper Job]

Insulation!!!!

 

Insulation only slows the rate of heat/cooling. The transfer process still happens - eventually

 

Without some form of heat added, the pipework/pumps/tank will freeze

[TaffyRon]

My outlet is 2 inches above, it was 2 inches below and we took in a gallon a month so I removed 60 bricks of ballast and its spot on now.

everytime my mrs returns from a car boot I have to remove ballast!

[Neil2]

 

Yes I think I understand how insulation works. but I thought it was to keep something warm (or cold) which was already warm (or cold) and being subjected to some sort of heating (or cooling). Lagging an outdoor pipe is to reduce the chance of freezing from wind chill effect as far as I can make out.

 

So, you put a water pump in a boat (no air movement indoors so no wind chill effect). No heating on the boat. If it gets cold enough then surely it will freeze whether or not you wrap a towel round it, unless the towel is in some way heated externally it will get cold like everything else. The wrapping of the towel may delay the freezing if the towel is warm when wrapped around but in the end it will get as cold as everything else and the water pump will freeze.

 

I have been known to fundamentally misunderstand simple physics while understanding the more complex things so maybe I'm being very dim.

As I understand it, pipe insulation stops the pipe and the water inside from reaching the same temperature as the "outside" air, but you're right in the sense it is only slowing down the process.

 

But in this country it's usually sufficient as we don't tend to get long sustained periods of freezing and the insulation will usually work long enough to cover the length of time the ambient temperature is below freezing point. Any form of insulation will do the same so i suppose wrapping a towel round your water pump is better than nothing.

 

I've done a lot of frost damage work in the past, and I have never come across a situation where an insulated pipe has burst, even in lodges and caravans which stand empty all through the winter.

 

Having said that, I remember the winter of, I think, 1994 or 1995 when we did have days on end of sub zero temperatures and I remember pipes underground freezing up and bursting.

[John V]

great freeze....winter 1962/63

[magnetman]

Yes I see it now, its the warming effect of increased temperature during daytime (normally) which would give the towel its insulating properties.

 

must say that I have left boats unheated in winter before and never had any problems, never drained down a water system or anything and nothing has broken so far. maybe keeping the water IN the system is better as it creates some sort of thermal mass or something. and it doesn't really get that cold in UK anyway, at least not yet...

[Neil2]

great freeze....winter 1962/63

Oh yes, I remember that one too. Funny though how as you get older there's a point at which snow and ice stops being fun and turns into a nuisance.

 

That one in the 1990's though, there were icebergs in Morecambe Bay I kid you not.

[magnetman]

I was moored in Cookham Lock cut on the Thames winter of 1995/6 I think it was, it froze solid (the lock cut I mean). Got a photo of it somewhere. A chap in a tug called White Heather which used to moor up near there at Cookham Dean/Winter Hill came through the ice, she had a 6 cylinder Ford cargo engine with a large propeller and she just about got through but it was thick. it even froze the main river in some places a little bit.

Edited December 3, 2014 by magnetman

[ditchcrawler]

 

I know of one partial sinking that occurred after an owner bought himself one and put it in with a temporary pipe poked out through a hull opening well above the waterline. The pipe was a bit too long for the job and was just dipping a little way into the water outside. This wasn't a problem until he pumped out the rainwater that had got in, switched off everything and went home. Why ? . . . because with the end of the pipe in the water outside and the pump down low in the boat, he had inadvertently set up and primed a siphon.

I know a boat that sank twice like that before they worked out what was happening

[Proper Job]

Was it 2009/2010 that had a prolonged cold spell of below zero temperatures for several weeks as well.

 

I know there were many boaters who ran out of water, coal (it must have been bad cos Dusty couldn't get through) etc

[ditchcrawler]

Was it 2009/2010 that had a prolonged cold spell of below zero temperatures for several weeks as well.

 

I know there were many boaters who ran out of water, coal (it must have been bad cos Dusty couldn't get through) etc

We almost got back to the moorings the night before, moored on the tow path opposite our mooring at Napton and couldn't move over the next morning so went home and left it. Friends from the moorings moved her over when it thawed.

[Naughty Cal]

Was it 2009/2010 that had a prolonged cold spell of below zero temperatures for several weeks as well.

 

I know there were many boaters who ran out of water, coal (it must have been bad cos Dusty couldn't get through) etc

Yes there was.

 

The ice in our marina was really quite thick at the extremities of the lakes.

 

One boat had to be cut out as the ice squeezed the hull. Luckily for them they were within the reach of a long reach crane from one of the car parks. The ice where it was cut from was 12" thick!

 

A block of it they cut out and chucked in the gate house took weeks to thaw out as the temperatures were so low for so long.

 

Don't want another winter like that in a hurry.

[magnetman]

12 inch thick ice? Is that metric inches

 

thats astounding

[Naughty Cal]

Its only a foot!

 

ETA: But yes we were amazed when we saw it.

Edited December 3, 2014 by Naughty Cal

[magnetman]

a foot thick ice. that is shocking (to me)

Do you know what they used to break it ?

[bizzard]

The shorter the boat the more sensitive the boats attitude in the water to fore and aft weight alterations.

[Gordias]

a foot thick ice. that is shocking (to me)

Do you know what they used to break it ?

 

I don't think canal boats could break 12" of ice frozen evenly across a canal. IIRC that's enough to drive a car on. It would probably support a loaded boat (if it wasn't dropped from a crane

 

They could have used their usual means (**) for breaking it while it was still thin, but I guess that would mean clearing the ice every day.

 

(**)

I've seen pictures of a boat used for this, with extra horse(s) and men on board to rock the boat to help break the ice. I don't remember if the bow of the boat was reinforced with metal or not, but it seems likely.

Edited December 3, 2014 by Gordias

[magnetman]

Definitely not but Naughty is claiming there was 12 inch thick ice which a cruiser was stuck in and that it was cut out of that ice and pieces of the ice removed to a building and observed. I'm interested in what one would use to cut 12 inch thick ice. Some sort of saw I suppose.

so yes I suppose I used the work 'break' incorrectly as it was obviously 'cut' not broken.

 

sorry :

Edited December 3, 2014 by magnetman

[Gordias]

heh - I assumed you meant what was done in "the good old days", and I happened upon a photo not so long ago (probably browsing the gallery here)

 

It's not hard to saw ice, though the blades look weird:

http://www.darkhousegearandtackle.com/products.php?Category_ID=9

 

I doubt they're common in the UK though - they probably went for brute force over finesse and used a chain saw

Edited December 3, 2014 by Gordias

[Murflynn]

Even in the bad winter of 62/63 when the Thames froze over for months the thickness never exceeded about 10cm. I know because I was a young lad and a canoeist; we used to break a hole in the ice at the club in order to take a quick dip every afternoon (wearing wet suits) as part of our fitness regime. 12" sounds a bit excessive.

[ditchcrawler]

Even in the bad winter of 62/63 when the Thames froze over for months the thickness never exceeded about 10cm. I know because I was a young lad and a canoeist; we used to break a hole in the ice at the club in order to take a quick dip every afternoon (wearing wet suits) as part of our fitness regime. 12" sounds a bit excessive.

Well I made an ice yacht to use on Filby Broads and cars were being driven along the rivers.