Water cooled exhaust

[DaveC]

Has anyone on here ever fitted (or had fitted) a water cooled exhaust sysyem on a skin tank cooled engine? I know it would need a pump to provide the water from the canal / river. Seeing mention of water cooled exhaust in the February edition of Waterways World has prompted this question.

 

 

Dave

[Phil Ambrose]

Has anyone on here ever fitted (or had fitted) a water cooled exhaust sysyem on a skin tank cooled engine? I know it would need a pump to provide the water from the canal / river. Seeing mention of water cooled exhaust in the February edition of Waterways World has prompted this question.

 

 

Dave

 

I would'nt have thought that there was much to be gained by this. The only thing I can see is the added complication of fixing a skin fitting to pick up raw water and having a weed filter to worry about. I doubt that having a wet exhaust would be any quieter. I say this as our last boat was a Broads Cruiser with a wet exhaust and although weed filter was easy to get at it did manage to pick up a small Perch which was a devil to get out as it's spines fixed it firmly in the perforated tube, likewise freshwater muscles get in and fix themselves inside.

 

Phil

[DaveC]

I would'nt have thought that there was much to be gained by this. The only thing I can see is the added complication of fixing a skin fitting to pick up raw water and having a weed filter to worry about. I doubt that having a wet exhaust would be any quieter. I say this as our last boat was a Broads Cruiser with a wet exhaust and although weed filter was easy to get at it did manage to pick up a small Perch which was a devil to get out as it's spines fixed it firmly in the perforated tube, likewise freshwater muscles get in and fix themselves inside.

 

Phil

Thanks for that Phil - believe it or not Vetus (the co mentioned in WW) seemed to want to put me off the idea as well. Back to trying to squeeze a Hospital silencer in.

 

 

Dave

[mrsmelly]

Has anyone on here ever fitted (or had fitted) a water cooled exhaust sysyem on a skin tank cooled engine? I know it would need a pump to provide the water from the canal / river. Seeing mention of water cooled exhaust in the February edition of Waterways World has prompted this question.

 

 

Dave

 

Hi and yes one of our two boats at work has such a system fitted.

 

Tim

[gazza]

Phil, you suprise me when you say you don't think it will be quieter. Most NB's sound like old vans to me. When water cooled they sound like proper boats, there's something about the 'sploosing' noise that sounds correct to me. And are noticeable quieter.

There are obvious draw backs with pump maintenance and filters to deal with, but a nice cool wet exhaust is far superior to a dry exhaust any day.

Our elysian is super quite underway, the exhaust exits on the waterline. At rest it gurgles away, underway the exhaust is under water so takes all exhaust noise away.

Induction noise is taken care of by a proper car air cleaner assembly, total bliss!

The exhaust skin fitting does nag at me from time to time, but regular checks at antifoul time and 45 odd years under her keel stop me worrying too much.

[Phil Ambrose]

Phil, you suprise me when you say you don't think it will be quieter. Most NB's sound like old vans to me. When water cooled they sound like proper boats, there's something about the 'sploosing' noise that sounds correct to me. And are noticeable quieter.

There are obvious draw backs with pump maintenance and filters to deal with, but a nice cool wet exhaust is far superior to a dry exhaust any day.

Our elysian is super quite underway, the exhaust exits on the waterline. At rest it gurgles away, underway the exhaust is under water so takes all exhaust noise away.

Induction noise is taken care of by a proper car air cleaner assembly, total bliss!

The exhaust skin fitting does nag at me from time to time, but regular checks at antifoul time and 45 odd years under her keel stop me worrying too much.

 

 

Hi Gazza, I think that the difference is that under way your exhaust is below water while ours was still above, puffing and glugging. Another factor is the exhaust/silencer factor, yours sound better than ours.

 

Phil

[gazza]

The old girl does have a silencer too. Dads not keen on the gurgling when stationery and would prefer to raise the outlet a couple of inches. For me its staying put!

I like the noise of a water cooled exhaust that exits above water line too. It's the regular squirt of water as the exhaust fills and then gets blown out I like

Slow reving vintage engines with dry exhausts are ok,

its the whizzy jap motors I can't take to. Hospital silencers are horrendously expensive for what they are, and you end up with a characterless, soulless boat.

[OldGoat]

The old girl does have a silencer too. Dads not keen on the gurgling when stationery and would prefer to raise the outlet a couple of inches. For me its staying put!

I like the noise of a water cooled exhaust that exits above water line too. It's the regular squirt of water as the exhaust fills and then gets blown out I like

Slow reving vintage engines with dry exhausts are ok,

its the whizzy jap motors I can't take to. Hospital silencers are horrendously expensive for what they are, and you end up with a characterless, soulless boat.

 

 

Wet exhausts are magic - well ours is at any rate.

However it needs to be sensibly built in. To my mind a skin fitting for the inlet is noit th best idea.

We were seduced in our hire days by Teddesley BC who fitted them to all their boats. The Milwards did it properly with a girt big mud box and a large slatted aperture in the hull. Ours is a 6x6 trunk welded in which extends above the waterline. When it does get filled with mud, there's always enough water to keep the engine cooled and clearing it out is "easy".

 

The engine is much quieter and the engine space is cooler too.

 

FWIW what clinched it for me in the early days was that I was always getting burn on my arms when delving into the weed hatch - 4 times at the top end of the Curly-Wyrley....

[gazza]

the elysian has a hull fitting that has a scoop at the trailing edge, this helps to force water up the weed filter. the filter is a 1 1/4" perforated tube that is 1 1/2' long, it too sits way above the water line. its a handy set up as when cruising very weedy rivers i can lift a deck board and rod the filter out while underway without having to stop and remove the filter.

we dont tend to suffer with mud too much on the anglian rivers!

 

agree with all your other comments. proper job!!!

 

when i said skin fitting i meant the exhaust outlet

 

the inlet obviously has a seacock which is shut everytime the boat is left. the exhaust outlet doesnt, and as it sits on the waterline it does pose a very small sinking risk if it was to fail

 

hope that clears things up!!

[nebulae]

I fitted an indirect cooled engine,as it replaced an air cooled Lister.Did not fancy trying to weld a skin tank into an old boat.The exhaust is very quiet.Cant hear it when holding the boat by the centre line.Fitted a Vetus filter above the water line which works well.Fitted a skin fitting instead of a mud box.This was a mistake. Biggest problem was that the exhaust had to come out at the side of the counter(because of the diesel tank)Had to fit a diverter to stop water shooting on to the tow path, which we then wrenched off.Most modern marine engines that can be used for sea going boats will have the option of wet exhaust.Should be possible to use the pump of one of these,even though you have a skin tank.

[stuart23]

One disadvantage I've had with a water cooled exhaust is the couple of times I've tried to get through stretches of duck weed...unsucessfully !

[gazza]

One disadvantage I've had with a water cooled exhaust is the couple of times I've tried to get through stretches of duck weed...unsucessfully !

 

It can be a pain, we are lucky that ours is accessible underway, so one steering, one keeping filter clear gets us thru. Some of the heavier weeded sections of the middle levels have proved a bit of a challenge though!

Don't have any probs with overheating under normal operating conditions, even when run at continuous high rpms

[PaulJ]

If I really wanted a wet exhaust I would stick to a skin tank (presuming one already fitted)as this is,as long as tank properly made,a simple, effective all year round way to cool your engine.

If you had a wet exhaust you would have to drain it down wintertime. If the same exhausts water supply gets blocked when in use, it does not take long for that exhaust hose to melt.

Better suited to open,deep or weed free waterways I think.

[ditchcrawler]

It can be a pain, we are lucky that ours is accessible underway, so one steering, one keeping filter clear gets us thru. Some of the heavier weeded sections of the middle levels have proved a bit of a challenge though!

Don't have any probs with overheating under normal operating conditions, even when run at continuous high rpms

So do you run the engine with no cooling while you clean out the filters?

[PaulJ]

So do you run the engine with no cooling while you clean out the filters?

Probably has one of those tube type filters (like all the wood boats used to)-strainer comes out the top, above water level,water feed is at the bottom an below water .

[ditchcrawler]

Probably has one of those tube type filters (like all the wood boats used to)-strainer comes out the top, above water level,water feed is at the bottom an below water .

Sorry if I am being dim, but are you saying you can pull the strainer out and clean it and there will still be water flowing through the engine?

[PaulJ]

Yep reckon you could if memory serves me correctly.

Not saying I would mind you...

[gazza]

Paul is correct, take cap off, shove a 1/2 diameter rod down it, hey presto a clean fillter without shutting engine down, the top of the filter tube is well above the waterline meaning it can be cleaned without removing strainer or needeing to shut the seacock.

 

A mate of mine uses a co2 fire extinguisher attached to a spare filter cap, quick squirt and its clear. It's part of his middle levels kit.

Working for a company that services fire extinguishers means he never worries about the cost of an extinguisher.....

Edited January 17, 2013 by gazza

[ditchcrawler]

Paul is correct, take cap off, shove a 1/2 diameter rod down it, hey presto a clean fillter without shutting engine down, the top of the filter tube is well above the waterline meaning it can be cleaned without removing filter tube or needeing to shut the seacock.

 

A mate of mine uses a co2 fire extinguisher attached to a spare filter cap, quick squirt and its clear. It's part of his middle levels kit.

Working for a company that services fire extinguishers means he never worries about the cost of an extinguisher.....

Thanks for that, I didn't know it was possible. Someone should tell the members of the boat club at St Neots who were struggling along the Old West this year.

[gazza]

It does get a bit snotty down there! Biggest pain for us is no weed hatch. Plenty of forwards and reverse usually shifts the weed off the prop.

 

Not all raw water cooled boats are as easy as ours to keep the strainer clear. My mates ormelite has a very low height filter, you can't take the cap off without having the seacock shut. He does have a weed hatch though.....

[PaulJ]

Thanks for that, I didn't know it was possible. Someone should tell the members of the boat club at St Neots who were struggling along the Old West this year.

Funnily enough-two of their members are moored about 30 metres from me :-)

[David Mack]

The Milwards did it properly with a girt big mud box and a large slatted aperture in the hull. Ours is a 6x6 trunk welded in which extends above the waterline.

 

So what thickness of steel is the mud box trunk? If this is permanently open to the water it surely needs to be treated as part of the hull and maintained accordingly. Do you black it insider whenever the hull is done?