Converting a dry exhaust to wet.

[nikosts]

Hi to everyone. This is my first post here, hope it's in the right place.

I have an old greek boat (this type is called "koutoulo"). It's about 16 feet long and has an old air cooled one cylinder Lister ST1 engine (about 10 HP). The exhaust goes straight up on the deck. It is rather noisy and we have always to be careful not to touch it etc, so I am thinking of converting the exhaust to wet.
There is an old belt driven raw water pump (visible on one photo) which will need a rebuild probably. I then also need a custom made mixing elbow, some meters of exhaust hoses, a water lift muffler, siphon break etc, a cost of about $150-$200.
What do you think about this? Is there a chance of having back pressure problems?

Thanks for any response, Nikos!

[kistinie]

First the idea to go wet is good for security, noise and efficiency under certain conditions
Of course back pressure will cost you HP and torque
In fact you can go for any solution but No AVOID "water lift muffler", W.L.M is inefficient and dangerous as back pressure bring CO and CO² out of junctions (may be not dangerous in your personal case of open boat)

Wet exhaust will make you gain torque and lower noise too by cooling down exhaust it makes it easier to pull it out, but you will get rust
Water cooled exhaust manifold will do the same without oxidation but is this available for your lister, i doubt ?

[nikosts]

Hi kistinie.
I just want to ask, what should be the difference between the "Water cooled exhaust manifold " that you propose, and a hose pouring water just after the exhaust manifold? Sorry for asking but I 'm not sure that I understood what you wrote.
Thanks again.

P.S. About back pressure. I think that if I can regulate the amount of water going into the muffler it would be ok. My opinion though...

[gonzo]

The easiest is to make a water sleeve. You make a pipe going around the exahust pipe but in never mixes with the gas. There is an exit hose for the hot water.

[kistinie]

Water inside exhaust gaz is terrific and efficient but, it rust and it get difficult to send gas up else water returns to engine, which is very bad idea
The Gonzo solution is great as it can be home maid and water stays out but a little less efficient. But again so much easier !

Gonzo, what kind of pipe ?
Coper pipe ?
Should be great as it can be soldered (brazed) with 316L steel

[apex1]

There is an old belt driven raw water pump (visible on one photo) which will need a rebuild probably. I then also need a custom made mixing elbow, some meters of exhaust hoses, a water lift muffler, siphon break etc, a cost of about $150-$200.
What do you think about this? Is there a chance of having back pressure problems?
Nikos!

Hello Nikos, welcome aboard.

You are already on the right path as your opening has proven. The parts you easily can buy at "Vetus" for example. Not the only supplier, but one who knows the business (largest supplier for the boatbuilding industry). No need for a custom made elbow.

There are many Indian made "Lister" clones at the market, if you need parts or a new engine.

The raw water pump you should fix anyway its your engines coolant provider.

As long as you have about the same length of exhaust pipe and hose, you have no higher backpressure! But stay above waterline with the outlet!

Torque or power do NOT increase (as our layman would tell you), a wet exh. usually is a little bit less efficient than a dry one. In this case your Lister will not notice, nor will you, if you loose 50Watt or so.

A wet manifold is a nonsense on such a installation (raw water cooler), and not available at the market. Leave it.

Do not use copper in the pipe material! Mild steel is the choice on the dry part (It has the advantage to corrode in a predictable and even manner, you can see long before it fails, that it will fail. Stainless brakes suddenly and unpredictable), exhaust hose is it between the steel and elbow, then you may use stainless for the through hull.

Lookup the Vetus catalogue online, as I remember they even give a installation hint.
Good luck!

Soldering copper and steel on a seagoing boat was the joke of the week! (Layman)

Sorry for asking but I 'm not sure that I understood what you wrote.

You must not feel sorry if you do´nt understand Kistinie! Nobody does!

Regards
Richard

[Lt. Holden]

Why not repair the coolant pump (which is necessary anyway) and put a stand off shield on the dry exhaust stack, I would attach a flapper type exhaust tip to keep out rainwater and stray cats.

[kistinie]

Coming back on 316 L steel brazed on coper.
I did this for outside use but not on a boat and it behaves well

In a salted environment what happens ?
Any picture to see ?

[apex1]

Coming back on 316 L steel brazed on coper.
I did this for outside use but not on a boat and it behaves well

In a salted environment what happens ?
Any picture to see ?

Try to find a good shool to learn about the basics of physics instead of asking here for free education.
Naturally no pictures! Who would be such a moron to make that?

Lt. Holden
I agree, a "Truck type" arrangement would be the cheapest solution. But no wet exhaust.

Regards
Richard

[kistinie]

Try to find a good shool to learn about the basics of physics instead of asking here for free education.
Naturally no pictures! Who would be such a moron to make that?
Richard


A forum is for free education and knowledge sharing.
Your general aggressive attitude and permanent sabotage is in total contradiction with the solidarity and fraternity sailors have shared for all eternity.
I am rather surprised that nobody tell you to calm down, behave with more respect, and that recurrent insults is not a way to talk and express ideas.
Do you suffer from a psychological disorder illness ?



This being said
What appends to coper tube brazed on 316L exposed to salt water ?
Oxydo-reduction is one thing, but experience speaks more...

[mydauphin]

Kistinie, I think certain people around here have lost their patients with you. I am ok with you, since you remind of my teenage son...

One rule in engineering or making stuff in general. Don't mix materials unless you really know what your doing. Because that will be point of failure. Dissimilar metals will also corrode, crack, shrink or generally fail. On a boat vibration and salt air will destroy even 316ss if not done perfectly right.

[kistinie]

You are always responsible for your own hanger and under no circumstance we can blame the others. It is our choice to be hungry not the other's choice.


Back to metals, yes of course, but here on earth i do not get any problem with this 316/Cu mix used for architecture. (seen also in London in one of the queen castle)

[dobsong]

Hi to everyone. This is my first post here, hope it's in the right place.

I have an old greek boat (this type is called "koutoulo"). It's about 16 feet long and has an old air cooled one cylinder Lister ST1 engine (about 10 HP). The exhaust goes straight up on the deck. It is rather noisy and we have always to be careful not to touch it etc, so I am thinking of converting the exhaust to wet.
There is an old belt driven raw water pump (visible on one photo) which will need a rebuild probably. I then also need a custom made mixing elbow, some meters of exhaust hoses, a water lift muffler, siphon break etc, a cost of about $150-$200.
What do you think about this? Is there a chance of having back pressure problems?

Thanks for any response, Nikos!

And a wet exhaust would make it even better! It would be very easy to convert to a quiet exhaust using a basic "wet" exhaust system - and heaps quieter.....

[kistinie]

you can get a wet exhaust also with dual fuel
When you run a diesel with butane or propane, added to the air inlet (like on a LPG car, exhaust will be producing water, do the test, it is surprising.
Water cool the gaz and lower back pressure, increase torque

This is not conventional, water produced may not be enough to cool down the pipe at high rpm and you need to manage 2 fuels...but it works great on slow motion

[apex1]

Nikos,
one thing I overlooked in your opening..........
the Lister is NOT aircooled, as you mentioned yourself, there is a raw water pump!
The whole installation is a pretty easy one and within your cost estimation. (I was impressed, that the "Truck type solution" is almost as expensive. I looked up at a highway truck shop.

Forget about the statements above (post # 14), all nonsense! Stay with us, stay alive (no gas on a small fisherboat), and do not waste your time and money with such phantasies. A water cooled exh. does NOT increase torque or power! The opposite is the case in a perfect installation! But I mentioned that above, nuts!

Regards
Richard

[apex1]

A forum is for free education and knowledge sharing.


Nice if there was any knowledge you could bring in here, but you are running novices into your idiotic theories.

There are simple and proven solutions, mentioned above. period

[nikosts]

To start, thank you all for your replies. You really help.

Now, Richard, don't worry I'm not going to install a nuclear or hydrogen or gas engine on my forty years old boat! The engine is really air cooled. The water pump was used to wash the deck and haven't worked for years.

I'll try to draw a simple plan of what I have in mind and post it maybe tomorrow. I will also write some links of things I consider necessary.

Cheers, Nikos.

[apex1]

To start, thank you all for your replies. You really help.

Now, Richard, don't worry I'm not going to install a nuclear or hydrogen or gas engine on my forty years old boat! The engine is really air cooled. The water pump was used to wash the deck and haven't worked for years.

Cheers, Nikos.

Welcome mate,
so, you have the originally "Lister" without a jacket?
But as you know, you MUst bring the pump up to work for feeding the elbow!?
Yes you know.
Have you seen the Vetus drawings?

Regards
Richard

[nikosts]

so, you have the originally "Lister" without a jacket?


What do you mean by "jacket"?
Yes I 've seen the vetus drawings, which are very helpful!
I 'll try to make my own drawings and post them.
Thanks...

[apex1]

What do you mean by "jacket"?
Yes I 've seen the vetus drawings, which are very helpful!
I 'll try to make my own drawings and post them.
Thanks...

Jacket is a surrounding cast (cyl.s, manifolds) made to cool the engine by water, either fresh or raw.

Jacket water is named the internal water (and antifreeze and thelike) running through the heat exchanger, raw water on the outer side. You do´nt have.

>>>> I 've seen the vetus drawings, which are very helpful!<<<<<<<<
Yes, I know what I am pointing to, thanks.
Post your ideas, welcome!

Regards
Richard

[nikosts]

So...
I made a drawing showing the main elements.

The van at the right of the engine will be used to reduce the amount of water going to the muffler, as it will be more than enough probably.
What do you think as you see it?

Total cost 175 euros, without the exhaust elbow. Any idea about that?


Thanks, Nikos.

[apex1]

So...
I made a drawing showing the main elements.

The van at the right of the engine will be used to reduce the amount of water going to the muffler, as it will be more than enough probably.
What do you think as you see it?

Total cost 175 euros, without the exhaust elbow. Any idea about that?

Thanks, Nikos.

Hi Nikos,
the exh. elbow, I think, you can make yourself. If you do´nt want the water as a deck wash source just let it run through. Save the valve. If you fear it is much too much water, then do as your sketch shows, but I would not make a second through hull, just let it come out after the exh. elbow (in the downstream of the elbow). It is another sound dampening factor there.
Which sort of mixing elbow have you found?

Regards
Richard

[nikosts]

I was thinking of get ridding of the excess water by pouring it in the exhaust hose just before it exits the hull.
About the elbow I may use something like the filter at the photo, without the strainer though, just the Y shape pipe. Then the pipe will continue for some inches so the exhaust gases are cooled before entering the plastic hose. The other option is the other photo, sure better but also 100 euros more...
By the way I add a second attempt of a "plan"...
Regards, Nikos.

[apex1]

I was thinking of get ridding of the excess water by pouring it in the exhaust hose just before it exits the hull.
.

That is exactly what I meant!

And that (see picture), would be a easy and cheap elbow! You could connect the hose directly! But take care, only in this (horizontal position!)
If you use something like your old muffler (emptied) it might be done for some pennies.

Regards
Richard

[mydauphin]

That is exactly what I meant!

And that (see picture), would be a easy and cheap elbow! You could connect the hose directly! But take care, only in this (horizontal position!)
If you use something like your old muffler (emptied) it might be done for some pennies.

Regards
Richard

Why only in horizontal position?

[apex1]

Why only in horizontal position?

In horizontal pos. the water is trapped longer to cool the outlet side sufficiently. In vertical, the gasflow maybe still too hot to install the hose directly at the outlet end. But any angle between 0 and 45° may work as well.

Regards
Richard

[CDK]

In horizontal pos. the water is trapped longer to cool the outlet side sufficiently. In vertical, the gasflow maybe still too hot to install the hose directly at the outlet end. But any angle between 0 and 45° may work as well.

Regards
Richard

Excellent advice Apex1.
If the installation dictates a vertical exhaust, the outgoing pipe must not be inline, but tangentially connected. The exhausts I made from stainless steel also have the water inlet tangentially, so the whole circumference stays wet.

[apex1]

Excellent advice Apex1.
If the installation dictates a vertical exhaust, the outgoing pipe must not be inline, but tangentially connected. The exhausts I made from stainless steel also have the water inlet tangentially, so the whole circumference stays wet.

Well, thats the "perfect world" ! But I was thinking about a cheap trick (no money) to achieve the task. And from Nikos´s drawings I do´nt see any need to be straight vertical.
One point to complain: as mentioned above, I would not use SS for exhaust, mild steel corrodes in a predictable manner and fails more even. You will notice long time before, that it is time to renew the part. SS fails suddenly and complete! That may be the difference between water pumped through and water pumped into your boat!
Regards
Richard

[mydauphin]

I have exhaust underwater, thinking of replacing with stainless. But know I am thinking PVC.... as per Frosty... ha ha .... Interesting SS failure you mention apex. My muffler are vertical and thought that was good idea to prevent water back flow. But may be 45 angle might be better... Got to check details and will let you know for advice.

[apex1]

I have exhaust underwater, thinking of replacing with stainless. But know I am thinking PVC.... as per Frosty... ha ha .... Interesting SS failure you mention apex. My muffler are vertical and thought that was good idea to prevent water back flow. But may be 45 angle might be better... Got to check details and will let you know for advice.

As always, you´re welcome.
Please do´nt mixup your installation with the simple one Nikos is asking for! Back flow should be prevented by elbows at the through hull. Nikos might not need them though! His through hull is far above waterline and according to his drawings he will go upwards with the exh. (as it was), before he goes down to the mixing device. If you do as CDK mentioned, there is no prob. doing it vertical anyway.
Or do it this way (is valid mainly for Nikos).

Regards
Richard

[kistinie]

Does this design with VETUS 40 muffler brings any back pressure ?

[apex1]

NO, not noticeable.

[kistinie]

Just read this Nikos before starting to work

http://www.proboat-digital.com/proboat/20070607/

page 94 "reducing the risk"
With special attention to page 98 on water lift muffler and elbow
It will help you deciding



And thanks apex as he brought this link to us

[apex1]

Forget about that, quickly! We are talking about a open little fishboat!

[kistinie]

Variable geometry :D

[nikosts]

I showed my drawing to a friend and he told me: why the muffler under waterline? Then I thought that all that I read on the net were about waterlift mufflers, which is not the case here. So what if I make the arrangement showed here? It 's much simpler and I think that there will be no back pressure issue. I'll do some measurements next time that I 'll be at the boat (in about a week) to see that everything fits. What do you think?
Regards, Nikos.

[kistinie]

Looks better

Check if you can Get rid of MP40 as a water lift muffler is not efficient, inject water as close as possible to the head with small droplets and avoid to sharp radius on all the line, spit exhaust at the stern as far as possible of objects (like rudder) that can reflect the sound to you, put a good oiled cotton wire mesh air filter (like for tuning on cars). Have an Ouzo ...

[apex1]

Looks better

Check if you can Get rid of MP40 as a water lift muffler is not efficient, inject water as close as possible to the head with small droplets and avoid to sharp radius on all the line, spit exhaust at the stern as far as possible of objects (like rudder) that can reflect the sound to you, put a good oiled cotton wire mesh air filter (like for tuning on cars). Have an Ouzo ...

Shut up ! layman !
all complete nonense (as usual), except for the Ouzo.

[apex1]

I showed my drawing to a friend and he told me: why the muffler under waterline? Then I thought that all that I read on the net were about waterlift mufflers, which is not the case here. So what if I make the arrangement showed here? It 's much simpler and I think that there will be no back pressure issue. I'll do some measurements next time that I 'll be at the boat (in about a week) to see that everything fits. What do you think?
Regards, Nikos.

Right, the higher you have the muffler the less resistance naturally. The most commercial systems work well below waterline though. look at the pictures below. (copyright Vetus) The left one is like your arrangement. And I doubt you need any additional muffler if you make a mixing elbow like I sketched.
You did not show a elbow near the through hull outlet but I assume there will be one!?

Regards
Richard

[kistinie]

Shut up ! layman !
all complete nonense (as usual), except for the Ouzo.

Whow ! You speak Vetus fluently !

Shut up= Rude behaviour
Layman = Amateur from Latin "amator" = a guy that love what he does.
i agree with you

[nikosts]

You did not show a elbow near the through hull outlet but I assume there will be one!?


I think I' ll skip the elbow near the through hull. The hose after the muffler has a gentle slope downwards, so I hope that 'll do! I don 't have the room for an elbow anyway...

[apex1]

I think I' ll skip the elbow near the through hull. The hose after the muffler has a gentle slope downwards, so I hope that 'll do! I don 't have the room for an elbow anyway...

Ok Nikos, Hammer this together and you can save the money for the muffler too. (if its still too loud, you can always add a muffler later) but it should do the trick...
The angle is something around 30° to 50° , make shure that the outlet is some 2 cm higher than the incoming pipe at the angle you install the barrel.
And make the outlet hose some mm wider than the incoming exh. pipe, thats adds to baffle the sound.

Regards
Richard

[M-Sasha]

Whow ! You speak Vetus fluently !

Shut up= Rude behaviour
Layman = Amateur from Latin "amator" = a guy that love what he does.
i agree with you

You are really a pain in the bu...! What drives you to mix up every serious thread with your drivel? And what sort of "advice" is this: "inject water as close as possible to the head"? Are you nuts? Stay away from the cyl. head with water, as far as possible!
Here is one giving real valuable advice, and this was mentioned by well respected members above. No need for your unmature and sometimes dangerous phantasies. Go play with your nonsense on your outer space threads.

Sasha

[Lt. Holden]

If the height angle of the exhaust pipe from the the elbow to the hull is close, simply use a rubber exhaust flap on the thru hull fitting and angle the hinge so that if slow the boat the water pressure will close the exhaust (the exhaust pressure will force it open enough to let the exhaust escape)

[nikosts]

You 're right. I 've though of that. I' ll have to do some measurements next time I 'll go to the boat to decide what I 'm going to do.
I 'll keep in touch with any progress.

[gonzo]

The diagram by Apex1 shows the vaccum break which is very important. It keeps water from siphoning back into the engine. Sometimes it is not installed and nothing happens for a long time until the boat gets heeled over or loaded in a different way.

[mrlrg1]

How do I change a wet exhaust on a jet boat with 350 v8 motor?

[apex1]

How do I change a wet exhaust on a jet boat with 350 v8 motor?

What exactly is your goal? Changing is easy........open your wallet and get it done.

[M-Sasha]

You 're right. I 've though of that. I' ll have to do some measurements next time I 'll go to the boat to decide what I 'm going to do.
I 'll keep in touch with any progress.

That is a long way to go to the boat yes?:P

[Marco1]

Hi Nikostos, you have a fine looking boat there.
You want to cool the exhaust down because of safety and noise concerns right?
However you have an air cooled engine that is noisy by definition.
I think your project is far too complicated for little gain.

A water cooled engine needs raw water to cool the coolant that cools the engine. This raw water needs to get piped out somwhere and so the cooling for the exhaust is a sort of fringe benefit. Some people use the exhaust to heat a water tank fortheir shower...sorry not suggesting you do that.

Others with a water cooled engine know of the downside of strains and rubber impellers imploding and so get rid of the whole thing and go kel cooled and dry stack.

You have an air cooled (no pump what a blessing) and a dry stack. No raw water pump, no danger of sinking and other niceties.

Why change it?

Noise? Build a proper muffler.

This is my idea. Keep exhaust exactly where it is. Have one pipe for the exhaust. If your original is 1.5" go 2". Your muffler can be built this way. Internal pipe 2" diameter straight trough say one meter long. External pipe 3.5" diameter, about 80cm long. The internal pipe will have a series of 3mm holes all along and all around.
Before you weld the external pipe on, you must wind insulating fabric tape, string or similar to cover all the 3mm holes. We used to use asbestos but obviously you don't want to handle that stuff so find suitable alternative. You also will need two reductions from 3.5 to 2". Weld the first reduction from external pipe to internal leaving some 100mm to join to the exhaust pipe. Stuff the space between the internal and external pipe with fibreglass. Weld the second reduction to join both pipes, leaving again 100mm.
Build a little metal flap so that when the engine shuts down it falls shut and stops the rain from coming in
Noise problem solved.
Burning issue. Add a shield around your muffler. You can buy them from wood fire stoves suppliers.
This way you keep simplicity and safety and don't have to get into adding pumps and exhausts and drilling holes in your boat.

[M-Sasha]

Good advice Marco!

No not yours, that was a bit late and did not hit the nail, the others on page back!


Sasha

[Frosty]

Remember the Vetus dimensions are minimum!! and not ideal.

Wet exhausts are a real pain to get right and many boats do not have the right Diameter.

Vetus warns you of this and you can phone them.

Once you mix water with the exhaust you need a 4 x increase in Dia than would normally be required.

You got a dry and you want to go wet!!!!!!!!!!!!