Engine Noise Reduction Material
- Thread starter FlimFlamII
- Start date
I just read something in SailMagazine about a spray on coating for noise reduction. I'm starting to do some research since it is on my "almost immediate" list of boat projects.
I am afraid that "good" and "thin" are kinda mutually exclusive terms when it comes to sound insulation.. The heavy foam with a lead barrier seems to be the best.. http://www.boatstoreusa.com/engine-parts-accessories/engine-gauges-accessories/soundown-ivf1010mnsft12-insulation-barrier-1x32x54/?utm_medium=googleshopping&utm_source=bc&gclid=CjwKCAjwxJnNBRAMEiwA8X_-QaJF4_KkU6RMwCYjQzqONd0TH7gzXrbvFaZuByhftBcK7MnpQsqouhoC86oQAvD_BwE Some of the automotive products are probably useful too, but not as good as the thick/heavy.. https://www.b-quiet.com/products/b-quiet-ultimate-50sqft
I put 1" thick purpose built sound insulation on my Catalina 30 several years ago and loved it. It allowed for conversation in normal tones in the cabin while the engine was operating at 2200 - 2400 RPM. The difference was amazing. It took a lot of work to fit it into all the little nooks and crannies but was well worth it. I'm going to try and put 2" thick material on the 380 where ever I have clearance. There is a wealth of information out on the web about engine noise and ways to mitigate different frequencies, and which frequencies are the most disturbing. It's enough to make your head spin. I only mention the spray on material since it appeared that the original inquiry had to do with what kinds of 'thin' material was available. I have a natural distrust of things I read in glossy magazines since they rely on the advertisements for much of their revenue. Anything I see there is automatically suspect. The article was brief with no follow up information. Sorry if I was at all misleading.
I used the self-stick 1" thick stuff on the underside of my stairs that cover the engine and noticed an immediate improvement. I also used a big sheet of thinner stuff on the walls in the engine space and that helped to a lesser degree. I did get a can of spray stuff to try on an area under the cockpit floor that is too rough for the self-stick stuff to hold onto, I think it's an automotive product. I may decide not to use it since I can't remove it once it's sprayed on - may epoxy something on that I can put a screw into with a fender washer to hold up the self-stick stuff. (I'm liking that idea more as I type this).
Ok I don't mean to steal this thread. But since we're talking about insulation.
If you insulate what happens to all the heat. Should you set up some kind of blower to remove the heat?
The sides and front of the engine compartment are insulated on my boat but not the rear. Am i missing something/
If you insulate what happens to all the heat. Should you set up some kind of blower to remove the heat?
The sides and front of the engine compartment are insulated on my boat but not the rear. Am i missing something/
Noise insulation, I think you have lead foil, mass loaded vinyl and open/closed cell foams as options
I used the one inch thick self stick insulation from West Marine to replace the original insulation which was crumbling do to age. Very pleased with the results. It has two layers of foam; an isolation layer and an absorption layer, separated by a layer of PVC, which makes it surprisingly heavy. I had the engine out at the time so access was easy. Use some corrugated cardboard to cut and fit templates.
A much cheaper alternative, especially if you know a AC installer and get free scrap.
DUCT BOARD
Read that link for sound and heat properties.
I built a "box" around my cabin AC unit out of scrap from my residential home AC installer.
Foil side out to emit the heat, but you leave one side of your engine compartment free of Duct Board or open for heat potential problems. Note the engine requires air flow for combustion air.
Jim...
PS: YES! another use for our magic tool, DUCT TAPE!
DUCT BOARD
Read that link for sound and heat properties.
I built a "box" around my cabin AC unit out of scrap from my residential home AC installer.
Foil side out to emit the heat, but you leave one side of your engine compartment free of Duct Board or open for heat potential problems. Note the engine requires air flow for combustion air.
Jim...
PS: YES! another use for our magic tool, DUCT TAPE!
Insulated or not, every engine must be vented. The design of the boat should accommodate it. Sound insulation must not interfere with venting. Most boats have some insulation in the engine compartment. On many, it can be replaced with a better product.
Ken
Mine has some foam and Mylar stuff that has rotted away and drops little black chunks of foam all over the engine compartment. I need to replace it, but the wiring harness, Cooling sytem, Exhaust, and throttle & Shift cables are mounted through it. I need to bite the bullet, and free it up and replace it. I would love to have a quiet cabin.
Originally, there was no insulation on my boat so anything will be an improvement...
I ordered some IVF1005MN32 INSULATION BARRIER 1/2X32X54. The shipping was about the price of the insulation... If it reduces the noise, it will be worth it.
Thanks for all your input.
Joe
I ordered some IVF1005MN32 INSULATION BARRIER 1/2X32X54. The shipping was about the price of the insulation... If it reduces the noise, it will be worth it.
Thanks for all your input.
Joe
https://www.jamestowndistributors.com/userportal/show_product.do?pid=9345
My advice:
My advice:
- You need mass to deal with low frequency noises (the foam doesn't have that)
- Use the pins (not just adhesive) with Sounddown -- or equivalent;
- There are some sources that might be less expensive than Jametown -- I didn't search.
- Eventually you'll want to wipe it down from diesel, oil, grease, or belt dust -- the finish should allow for a paper towel and little cleaner to police-up the engine area.
- .