Engine compartment soundproofing

[lyle]

I am considering adding additional soundproofing insulation to the engine compartment as I find the engine noise to be very noisy underway when compared to previous boats I have owned. Has any one else done this?

Lyle Hanna
"Serenity"
Hull #363

[tcookson]

Hi,

I am also unhappy with the engine noise level and was planning on installing sound insulation. A mechanic has suggested that the loss of air space around the engine may cuase it to run hot. Did you make this enhancement? How was the result?

Thanks - Trevor

[Golden Handcuffs]

I've noticed that the sound level in the cabin is very dependent on the engine compartment cover's orientation. Try wiggling it around a bit and see if it helps. One time, I had it "just right" by luck, and the sound of the engine was greatly reduced.

[Triumph]

The Previous post is correct. This first step is to eliminate all sound leaks. This is the most important thing to do and will have the most significant effect. Seal and gasket. Put a light in the compartment at night, and look for light leaks.
There are two other aspects. Blocking sound, and absorbing sound. I do not believe that you will be able to significantly reduce the ambient sound level within the engine room by absorption for two reasons. One, you can't get enough thickness of a fiberglass type material for low frequesncy absorption, and second, the compartment is relatively small and therefore there is little reverberant sound building up. Therefore, your aim should be to block sound coming through the walls and surfaces of the engine compartment. The best sound blockers have mass. They are not light weight fluffy materials. The more mass the better, like sheets of lead encapsulated in vinyl. Not that this is what you'll use, but just to give you an idea. Search the web for industrial noise control products.

Good luck

Bill
S/V Truimph #208

[Hans Grasman]

Guess I am "blessed" with being very hard of hearing and I have the option to switch off my hearing aids.
But seriously my crew always comments that the engine is rather quiet.
Also only used 30 gallons of fuel during the last winter season from Nov. 1 thru April 4.
We had a good season for wind in S.W. Florida.