Reducing Generator Noise?

[jacqueg]

I have a Honda 2000i. It's quieter than most, but it's hardly silent.

I've been wondering whether anyone has experimented with easy ways to reduce the noise. I was thinking about cobbling up some kind of foldable box to pop over it when it's running.

 

[Trebor English]

One thing I have seen on U tube is to put a hefty sheet of plywood at a 45 degree angle.  Noise hitting the board gets reflected down to the ground.  Dirt absorbs noise better than concrete.  Several sheets can reduce the noise in several directions.

 

[mjbeam64]

Youtube has a lot of videos of DIY generator enclosures.

 

[tx2sturgis]

Whatever kind of 'foldable box' or enclosure you come up with, make sure it is vented, and make sure the exhaust and heated and fresh air flow are taken into account.

 

[jacqueg]

Youtube has a lot of videos of DIY generator enclosures.

Yeah, I saw some. I didn't see any that were portable enough to fit in my van for traveling though!

 

[jacqueg]

One thing I have seen on U tube is to put a hefty sheet of plywood at a 45 degree angle.  Noise hitting the board gets reflected down to the ground.  Dirt absorbs noise better than concrete.  Several sheets can reduce the noise in several directions.

 Hmm, that might work, thanks!

I could slide several pieces of plywood underneath my mattress.

 

[jwhite]

How old is the generator ? I have one that I bought used and I love it but it does not work as good as it did.
I think mine needs a new muffler if that can be replaced because I think it's louder than I remembered it being ?
I went ahead and bought a new champion generator and it's alot quieter and best of all it has a wireless remote start it was worth it to me because it got to the point I could hardly start the honda and I had the carb cleaned a few times so it was costing me money.
I would never buy a pull start generator again.

 

[highdesertranger]

one little sheet of plywood between the generator and the way you do not want the noise going. for a Honda 2000i like a 30"x30" piece will do it. place the ply about 6" from the generator and not touching the generator at all. I would not lean anything against the generator or put it in any type of box. if you do you better have really, really good air exchange. we did the plywood trick on the ranch for many years it works great, and we did not have a quite generator. highdesertranger

 

[bullfrog]

I have used an old hollow core door, a large paver stone even rocks stacked up to make a wall. I have set the generator rubber feet on top of my spare tire which was laying flat on the ground. Anything within less than a foot of the exhaust will vibrate and seems not to work as well as when it is moved more than a foot away. Slanting it at a 45 degree angle seems to help as well. There are several things that I have not tried because they melt or are flammable. My generator has a spark arrestor and I have an old piece of screen in a frame that I free stand between the exhaust and sound barrier. I have been able to quiet the noise such that I cannot hear it 100 yards away at all mainly for the benefit of other people camping near by. My generator produced less noise than the Honda new I believe and I can’t justify carrying enough extension cord or materials to make it to where I can’t hear it running while in my camp. If somebody comes up with a fire proof, sound proof thick blanket you can hang on a collapsible adjustable frame a foot or so away on all 4 sides that works they might get rich in my opinion. Until then you pretty much have to live with the noise if you run a generator and sound travels much farther at night so only run it during the day to not disturb others. At night I can hear a generator running for over 300 yards behind a hill sometimes. One of the reasons I have considered using a Prius as a generator is it seems I don’t notice the noise a car makes running as much as a portable generator so I guess over time you can condition yourself to what bothers you when you hear the sound it makes!

 

[Malamute]

I have my Honda in a cargo box on a hitch mounted cargo rack. It has an air intake in the floor of the box and an exhaust and cooling air discharge out the side of the box. Its fairly quiet. One other thing, when I got the hard start capacitor to allow the gen to run on eco mode it ran much quieter as well, besides allowing the fuel to last much longer. If your normal load will allow running on eco mode, or can be adapted to it, it will run quieter.

 

[GntlStone]

What if you were to add some CM-Ceramics 31" X 24" X 1" 2400 F Ceramic Fiber Insulation Blanket 8# Pound Morgan Ceramics for Forges, Kilns, Stoves using 3M high heat adhesive to adhere it to the plywood facing the generator, closest to the hotest area. 

Also maybe look for some metal flagpole brackets and the corresponding size of emt conduit to create relatively light, cheap braces for the wood. Cut emt to a good length for desired angle, attach braces to board, insert emt & secure with screw if necessary. 

I was using the emt/flagpole bracket setup as a easy up/down way to rig a sunshade on my deck in AZ abd it worked well.

I would think the kiln insulation would also act as a good sound dampener as well as being mostly fireproof.

 

[Matlock]

I carry 2 sheets of 1" rigid polyiso EPX 2' x 4' (one side silver finish). They are duct taped along the long edge so I can fold them together for storage. I've used as a genny sound deflector as well as insulation covering my rear door keeping direct sun off that part of the truck.
Genny is Honda 2200i and is really quiet but normally I keep it 30' away.
When closer I use the EPX on end and half folded will stand if no wind. If windy, place genny downwind and use awning polls to keep from blowing away.

just my 2¢

 

[ckelly78z]

You might be able to use reflectix as a surround to reflect the noise back at itself. Use it like a barrier fence that you put up around the generator leaving the top open for ventilation. Make the circle about 3'-4' to give plenty of breathing space.

Another thought is to use the same relectix in a cone shape around the generator with a large vent hole at the top. This would bounce the sound waves into the dirt where they would dissipate You may want to cut some ventilation holes in this cone .

Both of these could be set up on rocks, or small 2x4 bits to allow ventilation around the perimeter of the base. Both of these could be framed with heavy wire to hold it's shape in the wind, and use the end of the wires to stick into the ground.

 

[hugemoth]

Simplest and most effective method I've seen is a simple A frame made of wooden dowels with several bath towels draped over it. Towels are great at absorbing sound.

 

[INTJohn]

Goto a junkyard and get a motorcycle or a skooter muffler. Make sure is not so small that it cause too much back pressure.
Google "motorcycle or skooter muffler to quiet generator", there's all kinds of krap on it.
INTJohn

 

[eDJ_]

I haven't heard anyone mention taking their generator to a muffler shop and having
something made for it.

Remember too, a lot of noise is generated at the air intake as well. A more custom air cleaner system capable of reducing noise may be worth considering as well. Car & Truck manufacturers put a lot of effort into the design of the air cleaner systems to reduce noise in them. Today car heaters are incorporating air filters in them as a way to cut down noise in the passengers compartment. Small gasoline engines rarely get this same
consideration. This may be because people have just become used to and have accepted
lawn power equipment/small engines as being noisy.

But there are RV Generator Mufflers you can find with Google. Air cleaners that help reduce sound may not be as easily found.

 

[bullfrog]

I noticed on my new generator the manufacturer had glued sound damper foam to the inside of the plastic case that forms the exterior surface of the generator and vents are on the bottom for air circulation as well. I think they are well aware that the quiet ones bring more sales and are doing as much as they can to reduce noise to the point performance is impacted. Be careful what you wish for as you may get it!

 

[Spaceman Spiff]

I haven't heard anyone mention taking their generator to a muffler shop and having
something made for it . . .

Remember too,  a lot of noise is generated at the air intake as well . . .

I have a small 3 chamber automotive muffler that I attach to my 2000W generator.  It reduces the exhaust noise to nothing.  But it takes up a lot of space, so it does not travel with me.

I have thought about making a blanket 'pup tent' to reduce the noise.

It wouldn't be hard to put a small circular auto air cleaner over the stock one or even replace it.

 

[jacqueg]

So many intriguing ideas, thanks!

In fact, I don't really mind the noise of my little generator. Being partially deaf has its advantages!

But I do worry about my neighbors. My preferred campgrounds cater to tent campers rather than large rigs. So I know that at least some of my neighbors mutter to themselves when I start my generator.

I just tried putting my generator under some bushes. It actually helped some. I think the easiest place for me to start is experimenting with plywood pieces, because they will not take up extra room in my van.