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Post by Deleted on Mar 7, 2019 9:40:47 GMT
I’m not familiar with this engine but at first glance it looks like a bog standard skin tank cooling system. To my eye the area of the tank looks small but I suppose the engine is relatively low powered (compared to our 43bhp). Could you measure the heigh and length of the tank (and thus calculate the area)? This will give us a good idea whether the cooling is adequate for sustained high power use, as the ability to dissipate heat is proportional to the area of the tank. Will do!
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Post by Telemachus on Mar 7, 2019 9:42:12 GMT
See my addition about baffles.
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Post by Jim on Mar 7, 2019 9:46:17 GMT
It seems to be a very common problem, one of my mates has the same problem, there are no baffles in his skin tank to slow the circulation, overheats on rivers. Given that there are calculations on skin tank size why don't builders use them, it's quick and cheap when fitting the skin tank in the first place to make it bigger.
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Post by Deleted on Mar 7, 2019 9:59:01 GMT
See my addition about baffles. Yeah, not sure I could say whether it does or doesn't.
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Post by Deleted on Mar 7, 2019 10:03:39 GMT
It is a canal boat.
Unless the original builder was tasked with making it fit for river work, it is one of a number of areas where costs are saved in construction.
Rog
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Post by Jim on Mar 7, 2019 10:09:38 GMT
It is a canal boat. Unless the original builder was tasked with making it fit for river work, it is one of a number of areas where costs are saved in construction. Rog Costs saved in construction? A couple of sq ft of steel plate, probably an offcut anyway, and another metre of welding. Red hot mooring pins are called for.
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Post by Deleted on Mar 7, 2019 10:16:02 GMT
I'm beginning to think for the few days time I'm saving going via the Trent, it might be worth just going via the canal. Then I don't need to worry about my engine overheating and can just get on with it. And I can go up the Anderton Lift, which would be a bit of (brief) fun!
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Post by NigelMoore on Mar 7, 2019 10:19:38 GMT
I’m not familiar with this engine but at first glance it looks like a bog standard skin tank cooling system. To my eye the area of the tank looks small but I suppose the engine is relatively low powered (compared to our 43bhp). Could you measure the heigh and length of the tank (and thus calculate the area)? This will give us a good idea whether the cooling is adequate for sustained high power use, as the ability to dissipate heat is proportional to the area of the tank. the other unknown is whether the tank has internal baffles, not immediately obvious that it does. Baffles should be in there to force the hot coolant to flow over the entire area of the tank, rather than just making a bee line between inlet and outlet - which severely reduces the effective area of the tank. Normally there would be some signs of longitudinal welding where the baffles are attached inside. Not only small, but overly deep. Even with crude baffles when a tank is this deep you can get a laminar flow of hot over cold water layers, so that at higher speeds the hot water does not contact the cold side of the tank. It was a feature of Springer’s design, which was even deeper than this one. Perfectly adequate for canals, but working hard against a tide they could overheat very quickly. I cut out the existing tank on Platypus and rebuilt with a larger area; only 12mm deep, and with horizontal baffles allowing same cross-sectional area as the hoses. With 55hp at near full revs it could punch down the Trent for hours at a time. Pushing against Thames tides with a 30hp engine in the previous incarnation had been virtually not worth the effort. Old tank – New tank –
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Post by Deleted on Mar 7, 2019 10:19:41 GMT
But economy boats (and I'm not saying Welly's is) are cheaper because of economies made in construction.
The size of the skin tank, and the man hours in construction are one such economy.
A friend had a very lovely, bespoke Liverpool boat built in 2001.
The first time he got something on the prop and had to go in through the weedhatch, he ripped his forearms to shreds, as the opening had been left rough cut, like a saw blade. First blacking he had remedial work done.
Rog
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Post by Jim on Mar 7, 2019 10:20:02 GMT
If you are travelling with the tide there shouldn't be a problem, its only if you have to go flat out for ages.
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Post by JohnV on Mar 7, 2019 10:25:44 GMT
I would agree .... that tank looks small for continuous hard running. as regards builders not calculating tank sizes, In my experience many canalboat builders are not boat designers.
Many are extremely good platers/welders and can beautifully shape steel but are not truly boat designers and are inclined to do things by rule of thumb. The tanks seem to be usually fabricated with the shell when to be honest, the type and size of the engine is probably unknown. The fitter could well be from a different contractor and unless a conscientious type might just fit what he was given.
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Post by JohnV on Mar 7, 2019 10:30:04 GMT
I’m not familiar with this engine but at first glance it looks like a bog standard skin tank cooling system. To my eye the area of the tank looks small but I suppose the engine is relatively low powered (compared to our 43bhp). Could you measure the heigh and length of the tank (and thus calculate the area)? This will give us a good idea whether the cooling is adequate for sustained high power use, as the ability to dissipate heat is proportional to the area of the tank. the other unknown is whether the tank has internal baffles, not immediately obvious that it does. Baffles should be in there to force the hot coolant to flow over the entire area of the tank, rather than just making a bee line between inlet and outlet - which severely reduces the effective area of the tank. Normally there would be some signs of longitudinal welding where the baffles are attached inside. New tank – That is a lovely bit of design and construction Nigel
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Post by Telemachus on Mar 7, 2019 10:34:17 GMT
New tank – That is a lovely bit of design and construction Nigel Yes I especially like the curved ends. I bet most skin tanks just have the baffle stopping shortly before the end, which is a flat plate.
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Post by kris on Mar 7, 2019 10:39:40 GMT
I'm beginning to think for the few days time I'm saving going via the Trent, it might be worth just going via the canal. Then I don't need to worry about my engine overheating and can just get on with it. And I can go up the Anderton Lift, which would be a bit of (brief) fun! There are plenty of river sections on the soar and no tidal Trent where you can give your boat a good run to see what the cooling system is like before venturing onto the tidal Trent.
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Post by patty on Mar 7, 2019 13:41:09 GMT
I'm beginning to think for the few days time I'm saving going via the Trent, it might be worth just going via the canal. Then I don't need to worry about my engine overheating and can just get on with it. And I can go up the Anderton Lift, which would be a bit of (brief) fun! That sounds a plan ... Why invite stress if theres an alternative?
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