Replacing sound proofing diesel engines

[trest1]

Hi,
Does anyone have any recommendations regarding products available for soundproofing diesel engines. Our current sound proofing is 12 years old and breaking down quite rapidly.
thank you for any assistance
Teresa

[Kenomac]

I'm also interested.

[Hudson Force]

Choices need to be made regarding expense, safety and the degree of sound proofing desired.

I've used the inexpensive performance auto firewall material that is formed of spun fiberglass with fire retardant between foil sheets. It's fire safe and cheap at about $1/square foot and found at performance automotive supply shops. It's satisfactory for my needs, but far less soundproof than more expensive materials.

Another route is to use the foam board materials at a similar expense and more effective sound proofing, but not as fire retardant as the dedicated "firewall" material.

The third route is the stuff that works extremely well that is high quality for sound proofing, but much more expensive. These can be easily researched for price at marine supply sources.

It's important to note that a huge factor in effective sound proofing is to be attentive to the joining of the material and sealing at doors and corners. Even the expensive stuff is of little value if you leave cracks!

My advice for the automotive firewall matting is only best for those that don't like to spend big money! It will not be the most quiet, but it can suit well!

Oh, and don't forget a good blower and ventilation. Diesels need good air supply. I run a effluent blower while running and a passive inflow vent. Sound-proof, but keep a good air flow from outside!

edit: I keep thinking of more! I said $1/sq.ft. for the automotive firewall, but I bought some last time about fifteen years ago. 'it's likely quite a bit more now!

[a64pilot]

Anyone have an opinion on which of the "good" stuff is best?
I'm quickly growing tired of having what sounds like a lawnmower in the Salon with us when motoring and am willing I think to spend some money if it will really help.
What I have I believe is roughly equal to the automotive stuff and surprisingly even though it's 30 yrs old, isn't falling apart.
It does do a lot as with the panels removed, it's incredibly loud. I've considered relocating the engine intake to the Lazarette as intake honk is a significant source of noise, but I still have a lot of just mechanical engine noise.



Sent from my iPad Pro using Cruisers Sailing Forum

[SailRedemption]

Originally Posted by a64pilot

Anyone have an opinion on which of the "good" stuff is best?
I'm quickly growing tired of having what sounds like a lawnmower in the Salon with us when motoring and am willing I think to spend some money if it will really help.
What I have I believe is roughly equal to the automotive stuff and surprisingly even though it's 30 yrs old, isn't falling apart.
It does do a lot as with the panels removed, it's incredibly loud. I've considered relocating the engine intake to the Lazarette as intake honk is a significant source of noise, but I still have a lot of just mechanical engine noise.



Sent from my iPad Pro using Cruisers Sailing Forum

I completely redid our boat's engine space and used a two layer system. First I painted on Sounddown paint from Defender. It's a water based paint you put multiple layers on. Then I came back and stuck the self adhesive tiles from Sailor Solutions. They work great and I honestly don't hear my Yanmar 4hj4-te 75hp engine that much in the boat. Most sound is from a mechanical noise, and if I open a inside engine access hatch it's a huge difference.

I did a write up on it on our site if your interested. It was super easy to do and it came out great.

See more @ redemptiverepair.com

[Pelagic]

Last year, I did a major refit to my engine room with the specific goal to lower than Db level while removing the sound shield around the generator to improve access.

I used all Soundown products
http://www.soundown.com/index_Marine.htm

The end result was very successful.
Keeping in mind that noise is 80% structure borne, suggest the you study their web site and primer on noise and vibration solutions first.

[SailRedemption]

Originally Posted by Pelagic

Last year, I did a major refit to my engine room with the specific goal to lower than Db level while removing the sound shield around the generator to improve access.

I used all Soundown products
http://www.soundown.com/index_Marine.htm

The end result was very successful.
Keeping in mind that noise is 80% structure borne, suggest the you study their web site and primer on noise and vibration solutions first.

Agreed there, most of the "noise" we here on our boat is mechanical. Hardly any is ambient?, not sure if that's the correct vernacular.

See more @ redemptiverepair.com

[bletso]

Vigah has a lead, yes, lead sheet around the inner bulkheads for sound/vibration damping. It seems to do the job.

[Rustic Charm]

I used the expensive stuff available and quite common here. It's got a layer of vynal samdwitched between two layers of foam and aluminium. My origional sound proofing had similar but the internal was lead. It had more sound compressing qualities with the lead. But, it's certainly better sound proofing than the cheaper foam only insulation..

[MarkSF]

Originally Posted by Rustic Charm

I used the expensive stuff available and quite common here. It's got a layer of vynal samdwitched between two layers of foam and aluminium. My origional sound proofing had similar but the internal was lead. It had more sound compressing qualities with the lead. But, it's certainly better sound proofing than the cheaper foam only insulation..

I used the stuff made by Soundown, which is sandwiched mass loaded vinyl. It was very effective. Used the 1" thick stuff mostly. I focused on noise in the cockpit, and used two layers under the cockpit sole and inside the access doors behind the companionway steps, one layer elsewhere.

The noise reduction in the cockpit is very noticeable, to the extent that most noise is from the exhaust now.

To the OP : where is your engine located?

[Scaramanga F25]

" Soundown Lead Accoustic Barrier" one inch or thicker is better.

[quandary]

A thought that might help...I have a landrover discovery td5 and I noticed that it had a very heavy sound insulating cover over the top of the engine (valve cover). When I removed this, the engine noise/diesel clatter in the vehicle increased dramatically. Of course it also has engine compartment and bonnet insulation but I think the main sound dampener is the cover on the engine itself.
One might consider doing likewise on your engine as well as insulating the engine room walls.

[jstevens]

8 years ago I went with the expensive, but easily installed stuff: LED lighting, soundproof, Sailor's Solutions Inc.

This product comes in 1'x1' squares 1" thick. I had several reason for going with this product in addition to the ease of installation.
1. I had limited space between the engine box panels and the engine itself, so insulation thicker than 1" would be a problem.
2. The engine box panels are fairly large, and I didn't want to add a lot of weight to them.
3. My engine configuration would be very difficult to fully sound proof as the drive train is open to the bilge. No matter how much insulation I put on the box panels a lot of sound was going to escape the engine compartment. Sealing off that drive train would have been difficult, expensive and created other issues.

My solution was a compromise, but it was very effective in reducing the sound level in the cockpit and at the nav station, which is right next to the engine box. The adhesive on the panels has shown no sign of giving out in 8 years. So I can recommend the product for installations similar to mine.

Sound Proofing

John

[davewtsnape]

I've not done it yet, but was thinking of using Armaflex Class O Nitrile rubber foam. Either self adhiesive or using EvoStik safe80 water-based.????

[wostenberg]

I'm looking at Syber Marine, and working with John 1 855-298-6996. He is very knowledgeable. Theirs is fire retardant sound proofing. I've had higher priority projects but will get back it this Fall.