sound insulating - generator area

I posting this in the general are instred of electrical - generator, because it is not really about the generator, but sound insulating the cabin from the generator.

I have a torque ss - toyhauler 5th wheel - with an Onan RV-4KW generator mounted in a typical location right behind the kingpin area.
The generator is housed in a standard relatively thin sheet metal housing. The sheet metal easily flex, simply by pushing on it with my hand. To me it almost act as a resonator box (if there is such thing).

There is a good amount of noise is being transferred to the cabin.
Has anyone attempted to insulated the generator box.
There is plenty room to encase the outside of sheet metal box with dense Styrofoam- all around.
will it work reducing noise and viboration sound? Or I am wasting my time and money?

thanks
 

kickinbar

Member
Hi... I have a Cyclone toy hauler and am thinking about doing the same thing. Here are my thoughts; 3/4" rigid foam on the top and sides. Will have to remove the wall to the storage area to do the back but that's not hard. Will probably use Liquid Nails to attach. Any comments are appreciated..
 

avvidclif

Well-known member
Mine is a lot quieter in the bedroom than outside. And I'm sleeping on top of the generator. No problem whatsoever.
 

HornedToad

Well-known member
I used a knock off of the Dynamat automotive soundproofing that was less expensive as it was petroleum based since it was an exterior installation. I was able to line the inside of the generator box before I installed a new generator.

The knuckle test was proof it was worth the trouble... One rap and you could notice reduced noise and vibration!!!


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Jesstruckn/Jesstalkn

Well-known member
I would use the automotive insulated sound mats it comes in many thicknesses.
sample
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Thanks for the suggestions.
My idea was also to use 1" rigid foam -home depot sells it and is being used as garage door insulator. And yes I was also thinking glueing it with liquid nail or other construction type adhesive.
I also like the idea of using automotive grade sound deadening.
After doing some research, I find some self adhesive insulation used with roofing and air duck insulation.
Some claim it is same as dynamat- but sold at home depot as a different purpose material. Cost much less.

thanks
 

Jesstruckn/Jesstalkn

Well-known member
I just wonder if in a real hot days that gen will push up to 200° I wonder if the foam board would melt in hot spots ????

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I don't think heat is an issue if the foam is placed on the out side of the box.
THe generator is air cooled via internal mechanical fan direct driven by the engine, and this fan pulls in a lots of air into the metal box (interior) and push it out on the bottom where the exhaust muffler area is.
So there is a good air circulation-air movement throughout the generator box.
The foam insulation is also used with roofing (insulation) just under the shingles and MSD boards with the aluminum foil on the back as radiant barrier.
If it is on the outside of the generator box, I don't think it will be an issue.
It is relatively inexpensive and not much of it is needed, a 4x8' panel should be enough. It is worth a shot.
 
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As I was picking up the rigid 3/4" foam from lowes...I toughstuff expanding foam. I will use it as glue material instead liquid nails.
I know toughstuff is an excellent glue... have you ever got it on your fingers? that stuff does not come off.
I will use it liberally to adhere the rigid foam.
Also to further stop any resonation..... I will install a single strip of fur strip lengthwise inside to stiffen the long lenght of the the sheet metal. 3-4 screws will also secure the foam better to the metal box.
It will be great.
 
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