Quiet Boating

[shroppie-ditchcrawler]

Has anybody any views on building an MDF box around the engine in a cruiser style narrowboat.

I think this will help keep the noise down, but am a little concerned on how much space to leave inside to facilitate cooling. Is 3 inches all round OK with the box resting on the engine bearers (thus about 6 or 7 inches clearance at the bottom, as well). Anyone done this before..?

[matt]

I'm working on my trad in a similar way - the engine is already enclosed, but I'm I'm going to re-do it with car sound proofing and move the airfilter and cooling outside of the box.

 

I think I understand the air filter implications now, I just need to find a suitable one - but I'm waiting for my dad to visit before I do anything on the radiator - he's a bit more experience on all this - it doesn't have a radiator as such at the moment, just a small plastic reservoir in the engine bay itself - it's looks a bit of a frig to be honest - the engine manual suggests it should be 'sea water cooled'. It doesn't run too hot though - 80 at cruising speed.

[Sir Nibble]

Matt, 80 is a good temperature to run at and I wish my BMC would get that warm at 4kts. I work in the motor trade and a friendly mechanic did some hunting through his catalogues with the result that I have a 2cv filter fitted. It comes as a complete airbox and pushes straight on to the inlet stub.

[John Orentas]

I'm working on my trad in a similar way - the engine is already enclosed, but I'm I'm going to re-do it with car sound proofing and move the airfilter and cooling outside of the box.

 

I think I understand the air filter implications now, I just need to find a suitable one - but I'm waiting for my dad to visit before I do anything on the radiator - he's a bit more experience on all this - it doesn't have a radiator as such at the moment, just a small plastic reservoir in the engine bay itself - it's looks a bit of a frig to be honest - the engine manual suggests it should be 'sea water cooled'. It doesn't run too hot though - 80 at cruising speed.

 

 

Matt.

 

Have a good look at your engine, it will not have a radiator, as it has a header tank your engine will almost certainly be 'Keel Cooled', you will find that there is a large slim section tank welded probably to the swim of the hull, hoses from the engine feed hot water to the tank and bring cooled water back.

 

The system works in the same way as a radiator but where a radiator gives up it's heat to the air the keel cooler gives up the heat to the canal through the hull side. As I have said before there is nothing to be gained by putting an air filter remote from the engine you should instead make sure the engine enclosure is very well ventilated.

[John Orentas]

Has anybody any views on building an MDF box around the engine in a cruiser style narrowboat.

I think this will help keep the noise down, but am a little concerned on how much space to leave inside to facilitate cooling. Is 3 inches all round OK with the box resting on the engine bearers (thus about 6 or 7 inches clearance at the bottom, as well). Anyone done this before..?

 

 

It isn't usual to box-in an engine in the way you describe, you will have access problems and it should operate in free air. It will get very hot in such an enclosure and remember the alternator and induction system need cool air to work efficiently.

 

The more usual way to achieve some sound proofing is to cover the under-surface of the deck boards with suitable material, thick heavy felt is good but it must be fire-proof, or you could go for the proprietary stuff but it is expensive.

[charles123]

Has anybody any views on building an MDF box around the engine in a cruiser style narrowboat.

I think this will help keep the noise down, but am a little concerned on how much space to leave inside to facilitate cooling. Is 3 inches all round OK with the box resting on the engine bearers (thus about 6 or 7 inches clearance at the bottom, as well). Anyone done this before..?

 

You could try sound insulation as has been suggested, I got a load of this from EBAY for about £30, they will probably still be available if you search. It looks like egg boxes, it is also flame retardant. I dont know how well it will work but I will give it a go when I get the fit out up to that stage

 

Charles

[Gary Peacock]

Before you start boxing in the engine take a look at the exhaust system and mountings, a good exhaust system and prevention of mechanical noise transmission can make a big difference. The stick on type soundproofing you see at shows is very good and that is what most builders use if requested by lining the engine bay.

 

A boxed in engine will warm up very quickly if you do not provide a lot of ventilation. I once got very fed up about a generator that was keeping us awake so we encased it in sandbags and that made it very quiet. That night all the lights went off! (The generator was on fire.)

Edited October 18, 2005 by Gary Peacock

[Capt. Shoehorn NB Juno]

What ever you do, avoid using carpet liner on the engine cover/ deck board!

Had a very scary moment soon after moving on to our boat, in the middle of the tidal thames when the engine cover caught fire

The stuff works quite well as sound proofing, but is about as fire retardant as kindling!

Until I get round to ripping it out and replacing it we have to cruise with the cover to one side and the exhaust system exposed, making us probably one of the noisiest boats on the water.

 

Gary,

Could you suggest a good supplier for the stick-on stuff you mentioned? What's the stuff called?

Edited October 20, 2005 by Capt. Shoehorn NB Juno

[John Orentas]

Are we sure about this, I have lined the internal surfaces of my engine enclosure with rubber under-lay material of the type that appears to have lot's of pyramids on the surface. Obviously it should not be anywhere near the hot surfaces of the exhaust system in the same way that the plywood is kept away but I would doubt that the material poses any more of a fire risk than the plywood enclosure itself.

 

Natural rubber or butyl is a preferred material used in warships and submarines.

 

See my post. Dec. 22nd. '04.........'Fit out Good Ideas'

Edited October 20, 2005 by John Orentas

[Capt. Shoehorn NB Juno]

John,

The carpet liner used on my boat is of the compacted fibre kind. Not sure if it is wool or jute or what the stuff is, and it's right over the exhaust so it got REALLY hot!

Fortunately the actual deck board is steel checker plate so at least that didn't go up as well!

 

 

I get the impression that the previous owners only recently fitted the new checker plate cover and lining and after that never ran the engine at full heat before we bought the boat. The steel checker plate is a great idea. It looks good, it's gonna last forever, it's low maintenance and non slip. But the choiceof lining was a bit shortsighted.

 

One idea I thought I might try was just removing the lining (what's left of it) in the area over the exhaust and then spraying or painting the rest with a fire-retardent substance.

 

There seem to be various fire-proofing paints and sprays on the market. Has anyone used any of these that they could recommend?

[buggsy]

Shroppie,

 

sorry for thr delay in replying but I have been trying to find where i purchased some sound insulation.

I first contacted TW marine and they sent me a useful leaflet on soundproofing an engine compartment and prices for the sandwhich foam style insulation. Paul Evans from this forum advised me of a manufacturer of this material in the Nottingham area but unfortunately I can't find any details. I remember for £90 cash i got loads which are stuck to all the boards, bulkhead and gas locker on my semi trad. I have a perkins d3 installed and this definately made a big difference. The old forum is now not working so if you like this idea try sending Paul a PM for his advice.

 

cheers,

 

Steve.

[Paul Evans]

If that was me (and I guess it was), I probably did a Google search for suppliers. I don't remember the details and, as buggsy says, I can't access the old forum to see what I did. Try Google!

[awatsonbcp]

Shroppie,

 

sorry for thr delay in replying but I have been trying to find where i purchased some sound insulation.

I first contacted TW marine and they sent me a useful leaflet on soundproofing an engine compartment and prices for the sandwhich foam style insulation. Paul Evans from this forum advised me of a manufacturer of this material in the Nottingham area but unfortunately I can't find any details. I remember for £90 cash i got loads which are stuck to all the boards, bulkhead and gas locker on my semi trad. I have a perkins d3 installed and this definately made a big difference. The old forum is now not working so if you like this idea try sending Paul a PM for his advice.

 

cheers,

 

Steve.

hi steve ...i bought the stuff you mention from TW Marine .it cost about 150 quid to do the underside of the cruiser deck boards which is quite a lot but it has made a noticeable difference and i can now hear myself think at full revs! i still had to fit some high temperature insulation above the exhaust pipe to stop it melting the insulation.

[nb maggie]

I have recently started remove a lot of the soundproofing put in the cruiser stern by the previous owner, so its interesting to compare - its slightly noisy but mainly the high frequencies (tappet type noises) but not much. Being a cruiser stern drained into the bilge I found that the soundproofing held far too much damp and rain water, keeping the bilge far damper than it need be.

[Sarah]

when we fitted out our criuser stern colecraft our main objective was a quiet boat .i boxed the engine in from the bulkhead to just behind the gearbox then along the width of the deck board,i put in a false floor to the level of the engine bearers so the box dosnt sit in any bilge water.it is all lined with the fire resistent foam from tw marine, who gave great advice on soundproofing and engine mountings.i fitted a water cooled oil cooler and the air pickup is outside the box.i fitted foam to both deck boards and scew them down with dzuz fasteners which are 1/4 turn and spring loaded it stops the boards vibrating and the noise getting outit also deters casual vandalism.we have used the boat like this for 3000 hours in hot weather ,on long river trips with no problems ,we usually get comments most days on how quiet the boat is.out of interest ifitted an oil temperature gauge the oil got just as hot with the soundproofing as without you have to remember alot of cooling on a vehicle is airflow across the sump which is made of thin tin to help

[stuart]

Still looking around for noise insulation products and found this supplier that seems a reasonable price.

 

Soundproofing acoustic barrier material

Film Faced Absorber/Barrier Mineral loaded barrier sandwich

SA25FF/B/6 weight: 5kg/m2

 

1200 x 900 x 32mm

£36.27

 

http://www.soundservice.co.uk/soundbarriermats.htm

 

I'm thinking of doing under the cruiser deck and the bulkhead into the cabin to see what happens. Would probably need about 6 sheets to do the job = £217.62

 

Seems to have good noise insulation of about 30-40%

 

 

Also certified on the fire front to FMVSS302 Self-Extinguishing and BS4735 Self-Extinguishing

Edited February 27, 2006 by stuart

[John Orentas]

Hi Stuart.

 

I have had some involvement with soundproofing issues in a previous life. It is the high energy airborne noise that is the major problem with boats needing absorption materials.

 

The only type that can be really effective is the one with a layer of high hysteresis energy absorbing lead sheet, without the lead the material simply acts as a diaphragm which moves in sympathy and passes on the sound waves virtually unopposed.

[dor]

Film Faced Absorber/Barrier Mineral loaded barrier sandwich

 

I am not sure of the exact specification, but this sounds something like what I have.

 

It is a fairly dense foam with three layers. One foam layer is about an inch thick, the other foam layer is about 1/4 inch thick. Between the two is a heavy density material about 1mm thick. I'm not sure what it is, but I don't think it is lead, although it may incorporate lead in its structure. Either way, it is there to serve the same purpose - i.e. to damp out vibration that would otherwise be transmitted through the foam. The outer face has a metallised film attached so the foam doesn't absorb oil/moisture. It is glued to the underside of the cruiser stern deck with Evostick.

 

It makes a huge difference to the amount of noise transmitted upwards, especially as the deck is 1/4inch aluminium deckplate. Probably less difference if using a wooden floor.

 

I don't think putting stuff on the bilkhead will make much difference as most sound inside the boat will be transmitted directly through the steel. Softer mounts and an Aquadrive/Python Drive is the only way to cut this down.

[stuart]

Hi Stuart.

 

I have had some involvement with soundproofing issues in a previous life. It is the high energy airborne noise that is the major problem with boats needing absorption materials.

 

The only type that can be really effective is the one with a layer of high hysteresis energy absorbing lead sheet, without the lead the material simply acts as a diaphragm which moves in sympathy and passes on the sound waves virtually unopposed.

 

Ah, they also do that one!

 

Lead sheet sandwich - SA25FF/L/6 - £43.99 (1200 x 900 x 31mm)

[leechy]

Hi Stuart

Done some shopping for this stuff recently.The same stuff you describe is around £86 plus carriage @£14 for 4 x 1000 x 600 x32 triple layer,fire proof ,foil faced ,NON adhesive back from TW marine ,They source it from Halyard the main supplier and they are around the same price.There are 2 more grades in facing at extra cost if you want tear proof, but the price becomes rediculous and another set of grades in thickness at 45 mm,but this stuff is around £76 for 2 sheets and it only reduces noise by around 5db at nearly double the price.The 2mm inner membrane is a dense pvc layer and cuts easily with a stanley knife.If you buy the adhesive backing this is more money again and i was told that it only works if the area you are fixing to is perfectly flat,smooth and free of moisture dust grease ect.In the end i went to Midland chandlers and bought exactly the same stuff but a slightly smaller sheet (900x600) £20.00 each .I used contact adhesive with a 2inch paint brush to fix and it worked a treat.I would say if you were sticking 6 sheets you would use a lot of adhesive as the foam sucks all the movement from the glue so buy say 2-3litres for six sheets .Another tip don't wait for the glue to dry ,as soon as both surfaces are coated put the sheet in place ,if you wait for both to dry as in the instructions and touch the surfaces together in the wrong position you have the first of many expensive mistakes

 

Hope this helps

[alan_fincher]

Still looking around for noise insulation products and found this supplier that seems a reasonable price.

 

Soundproofing acoustic barrier material

Film Faced Absorber/Barrier Mineral loaded barrier sandwich

SA25FF/B/6 weight: 5kg/m2

 

1200 x 900 x 32mm

£36.27

 

http://www.soundservice.co.uk/soundbarriermats.htm

 

I'm thinking of doing under the cruiser deck and the bulkhead into the cabin to see what happens. Would probably need about 6 sheets to do the job = £217.62

 

Seems to have good noise insulation of about 30-40%

 

 

Also certified on the fire front to FMVSS302 Self-Extinguishing and BS4735 Self-Extinguishing

Stuart,

 

This is a job I need to tackle at some stage, (in a 'trad' stern with engine at rear, just in front of steerer). I've not bought anything yet, but did start to investigate products a few months back, before other things got in the way.

 

What I can say, for certain, is that although at a first glance at specification on paper, a lot of these sandwich materials look similar, there does actually seem to be massive differences in quality, even for the same nominal overall thickness.

 

Although all mostly of the form:-

 

Layer of foil

Thick layer of foam

Layer of dense 'lead like' material

Thinner layer of foam

(Optionally) Layer of self-adhesive glue, (which I've been warned doesn't work half as well as sticking them yourself).

 

the make up of those layers can be very different.

 

I compared a small sample sent by TW Marine (32mm) to some in my local chandlery, (also 32mm, and possibly the stuff sourced by Midland Chandlers).

 

The TW marine stuff has a much denser more robust looking foam, much more resilient looking shiny outer surface, (but they do multiple grades of this), and in particular the 'lead like' layer is much more substantial.

 

I can't say what the difference would be in use, but suspect that the TW Marine stuff is inevitably going to be more effective.

 

That said, it's also more expensive, so you pays yer money and takes yer choice.

 

I thought I might get the more expensive stuff for panels near to the engine, clearly resonating, and possibly use some of the cheaper stuff on bits that look more marginal as to whether deadening them is useful.

 

Keep us updated on how you get on, and how effectrive, please.

 

Alan

[stuart]

Although aimed at a different market this is also interesting...

 

£64.99 for Box of 42 tiles (42sq.feet !)

 

1 foot by 1 foot by 1.4 inch thick (305mmx305mmx44mm)

 

http://cgi.ebay.co.uk/GCD-ACOUSTIC-FOAM-TR...1QQcmdZViewItem

 

I emailed the company to ask if they used them for other purposes and got a reply of...

 

We have had quite a few people using them in the hulls of boats and in Generators.

As long as they are not exposed to a naked flame then there should be no problems at all.

Regards

Dave Goldring

Edited February 27, 2006 by stuart

[Canal Shop Man]

As long as they are not exposed to a naked flame then there should be no problems at all

So it's not fire-retardent! And if you get a naked flame in your engine bay . . .get off quick

 

Buy the right stuff - it's fire retardent.

 

I'd agree with previous posts - we have two different suppliers and the dearer one is definitely better.

[stuart]

Buy the right stuff - it's fire retardent.

 

Well so is there stuff...

 

The tiles are made from Fire retardant foam. conform to BS EN13165:2001 and FMVSS 302

 

But your right, it just doesn't seem to be the right stuff.

Edited February 27, 2006 by stuart

[alan_fincher]

Well so is there stuff...

 

The tiles are made from Fire retardant foam. conform to BS EN13165:2001 and FMVSS 302

 

But your right, it just doesn't seem to be the right stuff.

Stuart,

 

Although others have made a case for rubber carpet underlay, as well as various types of accoustic foam for use in studios, theatres, etc, my guess is that the multi-layer stuff with the heavy 'lead-like' membrane in it will kill a much higher percentage of the noise.

I'm not saying other stuff will not help a lot, I just don't think as much....

 

If you contact TW Marine they will send you fairly comprehensive info on how that stuff works, and what else you need to consider to get the best from it.

 

Not cheap though, and from memory only supplied by them in multiple of 4 sheets, I think....

 

Alan

 

p.s. Don't seem to be able to see your pictures on your build blog, by the way. Get an error about not logged into Photobox. Do I have to register with Photobox to be able to see them, or am I doing something else wrong ?