Lister CS 18/2

[Timleech]

If starting and stopping is sluggish its generally the wrong prop. Too much "rule of thumb" and not enough engineering design. We know of one boat builder who fits the same diameter and pitch prop to all his boats regardless of length, hp and rpm. I suppose it depends on if you are happy with near enough or want it spot on.

 

In general, a large diameter, slow turning prop will be much better for starting and stopping than a smaller diameter faster turning prop transmitting the same horsepower.

That's why tugs have big props (or did, before they went to fancier systems). It's also one of the reasons why modern shallow draughted leisure narrowboats tend to be fitted with high horsepower engines, to overcome the limitations of a small propeller.

 

Tim

 

Edit to clarify - when I mentioned 'tugs' I was meaning real tugs, not narrow boats!

Edited December 16, 2012 by Timleech

[bargemast]

In general, a large diameter, slow turning prop will be much better for starting and stopping than a smaller diameter faster turning prop transmitting the same horsepower.

That's why tugs have big props (or did, before they went to fancier systems). It's also one of the reasons why modern shallow draughted leisure narrowboats tend to be fitted with high horsepower engines, to overcome the limitations of a small propeller.

 

Tim

 

Edit to clarify - when I mentioned 'tugs' I was meaning real tugs, not narrow boats!

 

 

That's exactly what I've always been told, and also what I've always done.

 

A slowly turning big diam prop with the right pitch will have more grip/bite in the water, than a fast(er) turning smal(ler) diam prop.

 

Of course the diam and pitch have to be calculated for the boat in both cases, but I'm sure that if you play the 'tug of war' with 2 similar boats with the same engine, but one with a slow turning big prop, and the other with a smaller size faster spinning prop, the one with the bigger prop will win.

 

Peter.

 

Thanks for the photos Richard, too bad they don't look at all like the CS-2 I used to have, and that I liked so much.

 

Still this is a nice engine too, glad I don't need a watercooled manifold for one of these.

 

Peter.

[Dorman]

Kevin, will PM you with my email address a.s.a.p. At the moment you don't quite have enough posts (five or more I think) to qualify to receive or send personal mails (PM's) through this forum.

 

In the meantime have pulled this image from facebook.

 

 

Looks to be normal JP2M with water-cooled exhaust manifold and silencer.

 

ETA: There do seem to be circular casting stubs on the curved parts of exhaust manifold where they enter the square section water cooled part. My own built two years later doesn't have these.

 

Martyn at M.P.S. will shortly be offering the marine exhaust manifold part # 11-13-202 newly manufactured - click on link.

 

Is it absolutely neccesary to have a water cooled exhaust or is this something you could do without on a low load application like a narrowboat? Just wondering as all my Listers are dry exhaust

[pete harrison]

What happened to the Lister JS3 that used to be in ST TUDNO ? (current engine August 1979 and still fitted May 2007)

[steamraiser2]

Is it absolutely neccesary to have a water cooled exhaust or is this something you could do without on a low load application like a narrowboat? Just wondering as all my Listers are dry exhaust

 

 

All the marine Lister JPs had them. They are a very effective silencer and look good. Are they necessary? For authenticity they are but it is a matter of personal choice. Loads of boats have dry systems without problems. As you can see the wet Lister silencer is a very complex casting to produce and a high quality one is very expensive indeed. Virtually all our clients who order JPs from us want the authentic wet system even though they cost £1300+ a pop. We produce them and even we wince at the price! Each bare casting is over £800 ex foundry.

 

We are considering the fabrication of a look a like dry exhaust system as an alternative but even that wouldn't be cheap.But you pays your money and makes your choice. It seems for the serious Lister enthusiast only a wet one will do!

Edited December 16, 2012 by steamraiser2

[by'eck]

In general, a large diameter, slow turning prop will be much better for starting and stopping than a smaller diameter faster turning prop transmitting the same horsepower.

That's why tugs have big props (or did, before they went to fancier systems). It's also one of the reasons why modern shallow draughted leisure narrowboats tend to be fitted with high horsepower engines, to overcome the limitations of a small propeller.

 

Tim

 

Edit to clarify - when I mentioned 'tugs' I was meaning real tugs, not narrow boats!

 

I tend to agree. FWIW I have 1200 rpm JP2M with 2:1 reduction driving 24" x 22" Crowther prop. I wanted larger diameter with lesser pitch as suggested by Crowther's, but that's the biggest that could be swung.

 

Nevertheless I'm happy with it all round with one particular observation whilst exiting double locks with a variety of modern engined/propped nb's alongside. We both drop into gear at the same time but (sometimes embarrassingly) my heavier boat still at idle (350 rpm), pulls out faster than the modern ones despite quite a few revs on.

[alan_fincher]

Edit to clarify - when I mentioned 'tugs' I was meaning real tugs, not narrow boats!

Well there's one person of my Christmas card list then!

[FMC Ling 317]

Now I have the Bolinder sorted Kev I think a tug 'o' war is on the cards though if you win I will cry..... ALOT lol :-p

[onionbargee]

going to measure up a JP wet exhaust tommorow and do a drawing for fabricating one in steel.

 

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