Generator too Noisy? You might want to try this.

[CornMan]

http://www.alpharubicon.com/altenergy/gensetquiet.htm

[FIGJAM]

I tried that with a whisper quiet motorcycle muffler.

90% of the noise comes from the mechanical noise of the genny!

[crstophr]

I also spent a lot of time and effort going down this road only to eventually give up and buy a pair of the honda style "quieter" inverter generators.

[ranger magnum]

I also tried mufflers on an old generac. Not much difference. Like fig said, the mechanics themselves are loud.

[CornMan]

Noted, thanks.

[Jackass]

Those cheap gennies like the one pictured above rattle like crazy, there is no cure. Too much vibration and cheap, thin sheet metal.

[Bob]

Generator too noisy? LEAVE IT THE FUCK HOME.

Asshole hexayurt camp a hundred feet from us had one of those cheap-ass generators rattling all day long in the open air, powering their fucking air conditioners. Ironically, a properly vented hexayurt might be the ideal housing for a cheap-ass generator.

[CornMan]

Again, thanks. I trust your guy's opinions. I'm glad I didn't pay to do this experiment myself.

[Jackass]

Ironically, a properly vented hexayurt might be the ideal housing for a cheap-ass generator.

On the plus side campmates in need of a "buzz" can go hang out with the gennie and have a "smoke out".

[Bob]

I fucking swear, I wanted to call in a couple of DPW forklifts and commit an atrocity on that camp.

You built eco-whitewash hexayurts, and you brought a Zeke Chaparral generator to run fucking AIR CONDITIONERS. Assholes.

[CornMan]

I was considering doing the muffler trick to our Honda EM650 to try to quiet it down a bit. I would never dream of offending neighboring camps with generator noise. We might be able to adjust our budget to sell the 650 and get an EU1000i.

[lemur]

wouldnt the back pressure created by adding such an exhaust system to a gennie maybe not be a good idea?

[CornMan]

wouldnt the back pressure created by adding such an exhaust system to a gennie maybe not be a good idea?

I would think so too, and maybe a change in jetting would be in order, but the site in the OP didn't state any problem.

[Jackass]

We might be able to adjust our budget to sell the 650 and get an EU1000i.

I doubt you'll regret that decision

[Trishntek]

There seems to always be an issue with noisy gensets and mine is certainly noisy. But like you say, up in the 7kW neighborhood, it's not just the exhaust making racket. I've been able to plant mine near the Mother Ship and shade it under the solar array. This blocks the noise from two directions and the other two are either street or another vehicle. It really doesn't take much to baffle the noise from at least 80% of dwelling spaces without annoying the neighbors.

I do have a baffle box I built two years ago and have yet to find it necessary. It is more of a PITA to service the genset with it in place than it is worth.

[gyre]

Not true that bigger ones are always louder.
Quite the opposite.

There are a zillion models of the chinese generators.
They all look alike.

I have a middle grade one, northern.
Fairly loud, but the harshness is way down.
It would help to reduce exhaust noise.

I have heard some that inspired to homicide on starting up.
Those really aren't worth your time.

Intakes can be as loud as exhausts.
Harder to silence, but copy a good car design.

It might be possible to damp some of the sheet metal or other metal to metal points.

Adding an exhaust system is easy tech.
You can reduce back pressure with good design and larger openings.
Too large a pipe can create bass resonance though.
There is a lot you can do in this area.

You can flow 400-500 hp through a 2.5" pipe and muffler.
I have a 400 ci running through a single 3.5" pipe and muffler with parallel cats.
You can do a generator exhaust.

Check first for more silent stock mufflers.
Usually the generator mufflers are the quiet ones though.
Briggs mower engines and sears have quieter mufflers for everything, often listed as generator versions.

You can always do better, but not as compact.

[gyre]

DP

So dirty always

[gyre]

Note for those that don't know:
Not all car mufflers are the same.

The cheapest decent mufflers are invariably the better quiet dynomax with guide tubes to turn corners, in a double pass.
Get a straight through for max flow.

Most european car mufflers are made this way.
Used ones will do fine.
So called glass packs are often fine too.
The cherry bomb is exceptional.
Note that they are directional.

[captain mcguiver]

We tried this muffler gag on our 6500 watt gennie. It cut down a little bit of noise, unfortunately, most of the noise is cylinders hitting and reverberating through the metal engine block. The best way to silence a Gennie is a baffle. The best baffle we ever built was a cube made out of four 4x8 sheets of plywood standing on end. This lifts the sound straight up and most of it is dampened. If you added carpet or insulation to the baffle it gets even quieter. Just make sure your muffler isn't right next to the wood wall. We also set our baffle on fire once, it was next to a car's bumper and melted it. DOH!

[ranger magnum]

Even with a flowmaster, you wont get back pressure with a small engine like this. Better luck can be had building a baffle box.

Back pressure is needed in a two cycle engine, but that isnt applicable here.

[CornMan]

We might get less back pressure if we drill holes through the muffler on this generator. We can get even more power if we keep the RPMs revved up really high. It should be elevated in the open air for maximum cooling air flow.