Engine Compartment Soundproofing

[UpGrady]

Anyone added soundproofing/insulation to their engine compartments?  I found some temperature rated stuff out there for not too bad of a price with a PSA backerthru Sound Proof Cow and Silent Source....just looking for anyone with experience with either.

[lineman49]

A friend of mine used 1" styro. house insulation with the foil backing a few yrs. ago & it is still working fine.

[CaptSpike]

I used Sounddown on my ocean boat. I still have a bunch left over. Too bad you weren't close you could have it. I have the 2x2 grade. It is 2" thick and has 2lb's of lead per sq.ft if insulation. Google Sounddown and you'll see the various options. Good stuff. Not cheap, but good.

 

Spike

[Chas0218]

Try some of that stuff they sell for cars Dynomat?  I think that is what it's called.  It is supposed to really deaden noise.  I would be careful using styrofoam because you might increase running temps inside.

[UpGrady]

Dynamat, I will look at it further as well... just wondered if anyone has used any of these for marine applications.

[Xxx]

I built my engine cover from scratch, the original one from Sea Ray was falling apart and was way to large, and I used the 1/2" fiberglass with the silver paper on one side and it made a world of difference!! I have a Merc. 350 and when trolling you can barely hear that it's running.

[ray koziatek]

duct board used for hvac work and mount it with insulation facing motor ,not the foil back, i have used it for close to 10 years with no problem

[big easy]

Soundown is the way to go,not cheap but very effective at cutting the noise,and made for marine applications.You can but it direct from them,although it can be less money at places like Hamilton Marine.

Here's a picture of my motor box with 1-1/4" soundown applied.it has a layer of 1/4"synthetic lead in it which according to them is a big help in noise deadening.

The stuff is pretty heavy..

 

http://www.soundown.com/index_Marine.htm

 

http://store.hamiltonmarine.com/browse.cfm/sound-reduction/2,720.html

 

 

 

Edited March 10, 2014 by big easy

[lakebound88]

I have the same stuff mentioned above. It makes the engine hatch a bit heavier but I have little noise if any at idle/ trolling speeds. I'm sure it makes a difference for running speeds too.

Nick

Sent from my XT907 using Lake Ontario United mobile app

[DannyL]

Soundown is the way to go,not cheap but very effective at cutting the noise,and made for marine applications.You can but it direct from them,although it can be less money at places like Hamilton Marine.

Here's a picture of my motor box with 1-1/4" soundown applied.it has a layer of 1/4"synthetic lead in it which according to them is a big help in noise deadening.

The stuff is pretty heavy..

 

http://www.soundown.com/index_Marine.htm

 

http://store.hamiltonmarine.com/browse.cfm/sound-reduction/2,720.html

 

 

 

 

I'd love to add that to my Islander but I don't want to bolt it through the aluminium cover.....

Any thoughts other than that way?

[Adk1]

Ok curious to know if this insulation increases the engine compartment temp. I have been thinking about adding something to the inside of my compartment as well.

[big easy]

Those arent bolts that you see in the picture.They are anchors with a flat plate on one end, and a serrated end on the opposite side.You apply epoxy adhesive to the end with the plate and fasten it to the surface you are sound proofing.Once you have the neccessary amount of them attached and the adhesive has cured, you push the insulation down onto them.The serrated end will protrude and you place push on covers onto them,which holds the insulation down.

They're similar to the push on nut type retainers you see on axles on kids toys or garden equipment. They look like bolts in the pic, but they are just push on caps

As for holding heat, that hasn't been an issue for me, and im running a 350 ci mercruiser.

Edited March 11, 2014 by big easy

[Adk1]

I am with you dannyL but man that stuff is expensive. Don't know how much I would need either

[UpGrady]

_{All good stuff.. thanks for the input... the two places I mentioned initially are about half the price of the sound down, but are reliant upon a pre done adhesive backer to adhere to the box...it appears to me that with sound down you are paying for the lead and a more extensive mounting system...}

[lost a lure]

Acoustic egg crate foam. Baha used it on my engine cover.

[Adk1]

Like the stuff you can buy at a mattress store?

[lost a lure]

Like the stuff you can buy at a mattress store?

Just stuff a mattress in there.

 

[Dukdog]

Soundown is the way to go,not cheap but very effective at cutting the noise,and made for marine applications.You can but it direct from them,although it can be less money at places like Hamilton Marine.

 

http://www.soundown.com/index_Marine.htm

 

http://store.hamiltonmarine.com/browse.cfm/sound-reduction/2,720.html

 

Hamilton Marine was exactly who I was going to suggest!! I got their catalog in the mail last week and noticed they had a bunch of soundproofing stuff. HamiltonMarine.com should get you to their website. 3 stores within an hour of me here in Maine. Rockport, Searsport and Portland! Love them!! Their in store bargains on rope ends are amazing! I've bought decent length pieces of double braid from 75 cents to $6.00!! I got a beautiful 108' piece of 3/8 camo for under $5.00. You can't even buy garbage rope for that!!!

rn  

[

[CaptSpike]

Soundown is the way to go,not cheap but very effective at cutting the noise,and made for marine applications.You can but it direct from them,although it can be less money at places like Hamilton Marine.

Here's a picture of my motor box with 1-1/4" soundown applied.it has a layer of 1/4"synthetic lead in it which according to them is a big help in noise deadening.

The stuff is pretty heavy..

 

http://www.soundown.com/index_Marine.htm

 

http://store.hamiltonmarine.com/browse.cfm/sound-reduction/2,720.html

 

 

 

 They recommended spray on contact cement. I pre cut all my pieces and then sprayed the inside of the engine cover. Wait a few moment and install. Dress up the seams with Aluminum tape and wala a professional looking job. My cover was wood so I did use some screws to "help" keeping the stuff in place. honestly i don't think it was needed. The contact cement worked great. The other method using standoff's and caps looks good as well. If you had the extra cash go that route. not worse than a butched up looking job.   BTW if your looking for cheap don't do it. I ran my boat for 2 yrs before upgrading my builders soundproofing to Sound down. I had significant hearing loss in my left ear due to the engine noise from just those two yrs of use.Spend the $$ get the good stuff.

 

Spike

[Adk1]

Spike, how much did you spend on the Sound Down altogether

[CaptSpike]

Spike, how much did you spend on the Sound Down altogether

That was back in 2001, I have no idea. If I looked in my expenses I could probably find it but not worth the effort. I do remember I bought more than I needed and have had the extra for yrs now. Nobody was interested in buying it cheap. I can't remember if it is still out in the shed or if I dumped it due to lack of being able to sell it.