Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Nov 5, 2020 18:19:23 GMT
I had a bullhead in the intake on the barge once. Very awkward to remove it. Luckily for me the bloke who built my little superyacht Dulcinea decided to use external keel cooling as a solution for both of the BMC 1.5 cooling circuits so no raw intakes and no jabsco pumps. And no holes in boat below waterline. Nice. For cods hake I hope all fish talk doesn't start to get contenchus. Pros and cons for both systems but on balance I'd take an indirectly cooled system over keel cooling any day. Woth keel cooling the system has to be spot on size, once you reach the limit of heat exchanging that's it, you are out of luck if you need to work then hard and the system can't keep up. A correctly sized indirect system has a vastly superior cooling capacity so long as the system is maintained correctly. There is no way I could have turbocharged our BMC if it was keel cooled I get about 50% efficiency through the the intercooler feeding it with an unlimited supply of cold river water. Dont forget, GRP boats lend themselves to indirect systems as keel cooling on a GRP means snaking a load of metal work through the underside of the hull, more often than not ists undersized and prone to damage/corrosion. One of the bigger advantages of a raw water system is a wet exhaust, safer engine bay temperatures, quiet exhaust and a reduction of soot. The disadvantages of through hulls, pumps and pipework are only an issue if you are lazy with maintenance. I take it your boat has dry stacks?
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Nov 5, 2020 20:30:06 GMT
Gazza, that strainer reminds me of the one on our Broads cruiser, it was a chuffing great brass thing in a 2.2 BMC commander. I found that one day we were running hot so investigated and found a small perch firmly fixed by its spines, it was a devil of a job to remove. Phil I've seen that style referred to as 'Norfolk Pattern' Works a treat, if the deck boards are set up so you can left them directly above the strainer any weed can be rodded out while underway - the top of the strainer being above the waterline means the boat doesn't become inundated with river water - unlike something like a Freeman which has a similar but much shorter strainer that sits well below the waterline We can cruise the Old West when it looks like a green carpet relatively hassle free 👍
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Nov 5, 2020 20:36:44 GMT
I had a bullhead in the intake on the barge once. Very awkward to remove it. Luckily for me the bloke who built my little superyacht Dulcinea decided to use external keel cooling as a solution for both of the BMC 1.5 cooling circuits so no raw intakes and no jabsco pumps. And no holes in boat below waterline. Nice. For cods hake I hope all fish talk doesn't start to get contenchus. Pros and cons for both systems but on balance I'd take an indirectly cooled system over keel cooling any day. Woth keel cooling the system has to be spot on size, once you reach the limit of heat exchanging that's it, you are out of luck if you need to work then hard and the system can't keep up. A correctly sized indirect system has a vastly superior cooling capacity so long as the system is maintained correctly. There is no way I could have turbocharged our BMC if it was keel cooled I get about 50% efficiency through the the intercooler feeding it with an unlimited supply of cold river water. Dont forget, GRP boats lend themselves to indirect systems as keel cooling on a GRP means snaking a load of metal work through the underside of the hull, more often than not ists undersized and prone to damage/corrosion. One of the bigger advantages of a raw water system is a wet exhaust, safer engine bay temperatures, quiet exhaust and a reduction of soot. The disadvantages of through hulls, pumps and pipework are only an issue if you are lazy with maintenance. I take it your boat has dry stacks? Yes that's all true. And yes Dulcinea does have dry stack exhausts. Custom made stainless steel with forced air ventilation to the silencer boxes if required. I've had both and to be honest firstly I am not interested in running engines at full power anyway and secondly a proper dry exhaust is very quiet. And Dulcinea is a steel boat with the keel coolers simply being channel sections welded on the bottom of the hull. Long and sinuous bits of channel section which do remove the rejected heat effectively.
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Nov 5, 2020 20:37:52 GMT
I felt like bloody Mr Magoo! Go and get some glasses then. You shouldn't even be at work if you can't see - a hazard to yourself and fellow workmates, and everyone else on the roads. I can read a number plate from 20m just fine - sadly I can also read the drivel you post on my screen from just 10" away. Glueing two bits of metal together peering at a high intensity arc has suddenly become a lot harder than it was 25 years ago - who'd have guessed? Like JohnV it's more a reminder of the ceaseless march of time rather than a disability; just think,I can easily get a pair of glasses, stopping you from posting an endless stream of drivel would be a far harder task.
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Nov 5, 2020 20:42:07 GMT
Plus the dry stack exhausts on here have a very satisfactory tone to them. Brrroom brrroom type of thing. I find it goes well with the torpedo tubes and the Multiple Rocket Launcher system And it is much easier to make smoke with these things than with a plop plop wet thing. And there are no holes in bottom of boat. I'm like "only holes I want in bottom of my boat are ones made by the enemy". It is basically the wrong strategy to put holes in the bottom of the boat. Anyone tries to put a hole in the bottom of my boat and they get a broadside.
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Nov 5, 2020 21:27:31 GMT
Plus the dry stack exhausts on here have a very satisfactory tone to them. Brrroom brrroom type of thing. I find it goes well with the torpedo tubes and the Multiple Rocket Launcher system And it is much easier to make smoke with these things than with a plop plop wet thing. And there are no holes in bottom of boat. I'm like "only holes I want in bottom of my boat are ones made by the enemy". It is basically the wrong strategy to put holes in the bottom of the boat. Anyone tries to put a hole in the bottom of my boat and they get a broadside. Nah, it will sound like a van having its neck rung to anyone outside the wheelhouse 😉 Holes in the bottom you say? We are down to 4, a reduction of 2 from the last time out on the slip. All 4 are absolutely essential :- 1 for the prop shaft. 1 for the engine cooling. 1 for the heads in. 1 for the heads out. Unbeknownst to me mouse was on a par with Vanguard and his dastardly speed log and through hull depth transducer. He too is now at a more sensible 4 sinking risks 👍🔨😵🍻
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Nov 5, 2020 21:40:55 GMT
No it actually sounds really good Ok so yes there are a couple of holes going out to the back of the boat but they are dealt with by two long greased stern tubes and additionally two boxes with dual lip seals and pressure oil feed. The latter have been decommissioned as it's a bit uncool to have an oil slick behind the boat inland but it's a good principle also used on lifeboats. Toilets on boats don't want underwater inlets or outlets. It might look like a good idea but again it's an enemy thing. You don't want holes in the bottom of the boat. Obviously shafting for the engines is going to often be an exception here. I'm like "zed drives yeah yeah yeah" Having said that I like these new electric pod drives a lot.
|
|
|
Post by JohnV on Nov 5, 2020 21:46:45 GMT
Sabina has a dry exhaust ....... and it's a very satisfying deep grumble of an exhaust note
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Nov 5, 2020 21:52:42 GMT
Sabina has a dry exhaust ....... and it's a very satisfying deep grumble of an exhaust note Does it come out through the hull side rather than through a pair of Peterbilt exhaust stacks? Like what @magnetman has... If it is through the hull have you considered running keel cooling alongside a wet exhaust? I know of several with this set up. Not quite the best of both worlds coupled with the drawbacks of both, a fair compromise though.
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Nov 5, 2020 21:56:05 GMT
Water injected dry exhaust system is handy for generators to make them quieter but main engines? Not sure about that.
I think Sabina H has a vertical exhaust system.
Not sure what a peterbilt is but the exhausts on Dulcinea are routed through either the radar arch when raised or lower level stacks when the radar arch is down.
You would have to see it to understand it but its actually a very well thought out arrangement..
|
|
|
Post by JohnV on Nov 5, 2020 21:57:40 GMT
It does indeed Andrew, a proper funnel up the back of the wheelhouse
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Nov 5, 2020 21:58:36 GMT
Water injected dry exhaust system is handy for generators to make them quieter but main engines? Not sure about that. I think Sabina H has a vertical exhaust system. It works on a 6 cylinder 5.7 Leyland and a 6.354 Perkins 👍😉
|
|
|
Post by JohnV on Nov 5, 2020 22:00:20 GMT
Ah but this is an 8 litre 6 cylinder
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Nov 5, 2020 22:00:25 GMT
It does indeed Andrew, a proper funnel up the back of the wheelhouse Ah right, that would present a problem!
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Nov 5, 2020 22:04:27 GMT
On Dulcinea the exhausts go out the top when the gear is up but obviously on the Thames it's folded down which brings the low level stacks into play via a hinges system. It's actually very clever. So clever I laugh every time I interact with it all that stuff up there just goes down with a rope as there are 3 inch diameter coil springs in the engine room. genius job and a real smile maker !! And that was at Lechlade which I can not fail to be happy about as well !!
|
|