SOUND BARRIER FOR ENGINE NOISE

[popeyefoghorn]

Hello all...I have a 1978 Chris Craft Catalena Express Hardtop, 29ft. single 305. I would like to install a noise barrier inside the engine compartment. Has anyone done this. Also, are there any kinds available that would secure to the rough fiberglass finish on the under side of the compartment. thanks, eh!

 

[Boatist]

Re: SOUND BARRIER FOR ENGINE NOISE

I redid mine when a lot of the insulation was comming loose. West Marine has several noise reduction kits but they are way over priced.

I went to an ace hardware and they had two type of insulation I felt would work.

One was like those bubble you pop with a foil like cover on one side but it was only about 1/4 inch thick.

The other came in 1/2 or 1 inch thick blocks. It is a stroyfoam that has a heavy foil on one side. I used the 1 inch thick block and cut it to fit. Then I glued in place with silicone seal. Any where that that bolts went into the engine cover I used a longer Stainless Steel bolt with a nylon lock nut on the inside. I use either real large stainless washer or some aluminum flat bar under the nuts. Last I sealed all the edges with the metal duck tape.

Before I bought from the store I ask what the product was used for. The reply was that it was used next to stove to keep cabnets or wall cool. This product is real ridgid so only works on flat surfaces.

The bubble was very flexible.

 

[DaveM]

Re: SOUND BARRIER FOR ENGINE NOISE

You can find insulation kits at JC Whitney as well. Some say the acoustic material used by car stereo autophile nuts works well.

 

[popeyefoghorn]

Re: SOUND BARRIER FOR ENGINE NOISE

Is this stuff fire retardant? the real thing from west maine is very expensive. When you attached it, you say you just used silicon, anything special? I don`t have the option to bolt through the hatch covers...or I guess I should say, I would prefer not to. But I don`t want the stuff to fall down.

 

[Boatist]

Re: SOUND BARRIER FOR ENGINE NOISE

I do not believe the styrofoam is fire retardent but the foil is. My engine cover has lots of room between it and the engine and the cover is wood and vinal.
I used silicone seal because I felt it was less likely to melt the strofoam. In my case I have a teak wood rail on both side of the engine cover that bolt to the cover and hold up stern seats on each side of the engine cover so that is where I used the longer bolts. However on the front of the cover only have four bolts that hold a vinal storage pocket on. The front also starts out stright up then leans back the rest of the way to the top. Since this stuff is rigid had to cut it there so could make the turn.

Been on the boat about 8 year now and still looks good.

I was worried about fire also until I looked at the old stuff. It was basicly a peice of heavy plastic like a garbage bag covering the wood.

 

[popeyefoghorn]

Re: SOUND BARRIER FOR ENGINE NOISE

Hey, the carb has a flame arrestor on it...can you put a regular breather on and would that quiet it down a bit??

 

[speedholes]

Re: SOUND BARRIER FOR ENGINE NOISE

Dynomat, that is the car audio stuff. Back in HS, a friend of mine bought some for his trunk lid. We brought it home and realized that it closely resembled tar roofing paper. His dad is a contractor, and had huge rolls of the stuff lying around. We compared, and indeed, Dynomat is no more than roofing paper with adhesive on the back. $25 for a 4x4 square or an entire roll of roofing paper?

Go to a hardware store and get a small roll of roofing paper. Then go to Napa and get 2 cans of automotive headliner spray glue. Glue the roofing paper to the inside of you engine cover and whereever else you want it. We did this to car doors, hoods, trunk lids, etc. It really works pretty well for a really cheap fix.

 

[dhoptay]

Re: SOUND BARRIER FOR ENGINE NOISE

try home depot or lowes look at the insulation blankets that you would use on a hotwater heater, much cheaper.

 

[Kwas]

Re: SOUND BARRIER FOR ENGINE NOISE

I had cabin Cruiser that had the engine under the deck. I used 1" rigid fiber glass insulation completely under the deck and in the bulkhead of the cabin. It was amazing how much that reduced the noise.

 

[Boatist]

Re: SOUND BARRIER FOR ENGINE NOISE

Coast Guard requires a flame arester. It is a big saftey iteam. If you boat off shore today you will eventually be boarded by the Coast Guard. They check every thing from registration to Flame arrester. Everything on the required saftey check list is checked. Flares out of date usually the thing that they cite for the most. Life Jackets or PFD not it good condition is likely second.

Boarding since 911 has increased many fold. Also most bridges along the coast have a minumin distance and if you go too close your will be cited.

 

[edwardh1]

Re: SOUND BARRIER FOR ENGINE NOISE

we used Soundown, off the web from a marine sound reduction company in Fla and new england. works very well, can buy different thicknesses.
If the Japanese made boats they would proibably be quieter, mercruiser ignores engine noise.

 

[hudman]

Re: SOUND BARRIER FOR ENGINE NOISE

What city are you in? Go to an upholstery supply house, and buy Fire retardant foam, it is usually dark grey, they also will have spray adhesive to glue it to wherever you want to put it, some suppliers can cut to size, in slabs, 1 in or thicker....its a simple job, hour or tow at the most

 

[stevieray]

Re: SOUND BARRIER FOR ENGINE NOISE

Fire retardant foam.....isn't that the stuff that was on the walls of that nightclub in RI that burned down when Great White was playing??? I'd have the tendency to want some metal foil on the exposed surface. Behind that, the thicker the foam or fiberglas insulation you have, the better the noise reduction will be.

 

[SeaRay24Sorrento]

Re: SOUND BARRIER FOR ENGINE NOISE

I've bought alot of noise dampening/deadening products from these guys in Seattle and have used it in just about every application imaginable: cars, boats, engine areas(yup, I can barely here my disposal in my kitchen sink as well). Check out there site http://www.hamiltonjet.com/pages/NoiseandVibrationProducts.html