Sooty Backside

[ChrisP]

One for the panel anybody can have a go.

How much soot do you get deposited on the back of your boat ? Serious question. Friend of ours gets so much soot on the back of the boat when underway that it has to be washed off after every trip. Has any boat designer found a way around the vortex that is created behind the boat that holds the smoke against the boat. You can see it as he’s going along.
His exhausts exit through the transom on either side at stationary water level with 2 foot st.stl extensions on the pipes and he carries a rib on the davits. The engines are well serviced Sabre’s (Ford) Nothing seems to make a difference with the exception of a mixture of white diesel and Soltron. But there’s still some smoke.

What’s the back of yours like and have you found any designs that don’t have such a problem ?

I know breaking the vortex will solve most of the problem but how can you do it?

Idea’s !!!!

ChrisP ;o)))


What do you mean the sea gull in front's walking !!!

 

[wakeup]

What type of boat is it?

yada yada..

 

[Chris_d]

Petrol engine seems to fix it for me....
I guess you need some gurney flaps on the trailing edges of the transom sides, but boat speed is so slow they would have to stick out about 2ft either side, I guess flybridge aft cockpit boats are the worse, so you would need some kind of big extension to the flybridge to move the vortex backwards, but this would be behond the transom so would look horrible. I guess most designers try to forget this and concentrate on fashionable styling, this will sell more boats than some aerodynamicly efficent design.

 

[Deleted User YDKXO]

Tell him to try going everywhere in reverse, that might help

 

[hlb]

Mine stopped the minute I put ******* in it.

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Haydn

 

[rich]

I reckon his over proped, or to much weight on board,

rich )

 

[DavidJ]

Is this one of the rare positive arguments for a stern drive.
David

 

[simongoldthorpe]

What's under these asterisks - I am fascinated.

 

[hlb]

Suerly you do not need to ask.

<font color=red> No one can force me to come here-----------
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Haydn

 

[simongoldthorpe]

7 letters.... er no don't get it.

 

[DepSol]

I heard Ford Sabres are smokey anyway somat to do with the design.

Dom

I am boating again ;-)

 

[JeremyF]

Love handles

As a fresh convert I feel I'm allowed to comment. Ive now understood now that a dirty plume of smoke is de rigeur, but if you set up the love handles properly they should deflect it out of the vortex. Try adjusting them a little.

What colour is the soot. PaulineB claims here's are all natural, but that shade of Cilla red is deeply suspicious. I think its from a bottle. Clairol meets Soltron!

<font color=red>Jeremy Flynn/forums/images/icons/crazy.gif
Dawn Chorus</font color=red>

 

[Guest]

I presume you are talking about touch of class, basically with those 320 sabres theres not much you can do because of the old design of fuel injection system and hotter turbocharging, the engines need to be run a a high speed to burn all the fuel thats going in, but the pumps and injectors may be getting ready for an overhaul/service also the turbos might not be boosting as they should and last of all the intercooler matrix will be well ready for a strip out and degrease/clean.

paul.js

 

[Guest]

Mine does'nt get sooty transoms cos she was fitted with exhuast extensions which pass under the
bathing platform . This dispite having older Perkins turbos.

"The Med has got me" (no not the Medway the other Med)

 

[rich]

Yes they do, i had 212hp,it filled the harbour whith white smoke on start up, the manuel said, and this is gospel,,,,,,,,,,,Let all your lines go, Start the engine and get out fast, and go to full power ////////it worked every time.

rich )

 

[burgundyben]

Sabre used two Ford blocks mainly I think, Dorset, which smokes like a bastard and Dover that does not, then they changed sabre engines to perkins base units I think, any how, many Fairey boats use Dorset blocks complete with muchu smoke, apparently its somtething to do with the balance of compression and turbo boost leading to incomplete burn as mentioned by Paul JS, anyhow, apparently, the much quoted Lancing Marine do a de-smoke kit that has been highly acclaimed by at least one boat owner that I know, as always, before modifying, check condition, maybe as paul said, check fuel pumps and injectors.

For sale, 1970 Triumph Spitfire-sold, 1947 Lambretta, 1922 Great grandmother, PM for details.