3000W Chinese Gensets Info.

skyzoomer wrote:
Did this conversion make the engine any quieter than it was running on gas?

To answer a few of skyzoomer's questions: Black text is my stuff, blue is Zoomers.



Gas tank is removed.

I don't know how easy that was on the Eliminator but it looks impossible to do on the Champion C46540 without removing "everything" below the gas tank.


Same thing. Four bolts and the fuel line and the gas tank is out.

Sound absorbtion panels are made of fiber board sheathing.
What exactly is that? Normally used for what?

Sheathing used on the walls of a house, before the siding, brick, etc. is applied. Absorbs sound well, can be cut with a knife. But, not too waterproof. Uncoated side can be soaked with polyester resin or varnish to make a more rigid, weather resistant panel. Ultimately, I am looking at making a new frame from 1-1/2" x 1/8" angle iron (I have a welder) and attaching Filon (fiberglass) panels to a sound absorbing material like the sheathing with glue. The Filon will give the exterior weatherproof housing. BTW, Filon is available at Home Depot or Lowe's for around $25 for a 4x8 sheet. The sheathing was $6 for a 4x8 sheet.

Sound level was an extremely low 59 dB at the standard measurement distance of 21 feet. This is Honda 2000i quite!

Excellent! If the rest of us can achieve that we would be VERY happy.

It is achieveable. Keep in mind you have three sources of noise from the Chinese gensets: Exhaust, fan noise and mechanical noise from the engine and alternator. Exhaust noise is low as the genset comes, what we want to do is block the fan and mechanical noise. Another plus is the level of noise left is not as objectionable. The frequency of the annoying sounds you hear is reduced or changed. My wife and daughter came out to about 25 feet from the contraption when I was testing. The noise level was not even enough to interrupt their conversation and consequently they did not even notice it was running.


Like I said earlier, I believe the key to successfully building a compact enclosure is to get the muffler outside the box to reduce heat and ...snip

So using the stock muffler outside the box results in Honda quiet? Or did the wood sides of the platform the generator is sitting on help to muffle the stock muffler?

No, no, no. Getting the muffler outside the box only reduces the heat build-up inside the enclosure. It does not change the sound. Getting heat out allows you to make a smaller, tighter enclosure. I also plan to wrap the internal exhaust pipe to the muffler with heat wrap used on exhaust headers to further reduce inside heat.

The use of propane as a fuel also has nothing to do with sound. In my opinion, the enclosure is safer with the fuel tank remote to the enclosure. Since the tank is large and would take up additional space, why not use the RV's on-board propane supply? No extra tanks and a safer, cleaner fuel. Also, the metal tank on top of the engine acts as a sound conductor, even with gas in the tank.

Propane conversion is EASY and SAFE if you understand the process. It also can be inexpensive. Initally, the term "propane conversion" sent a chill up my spine. Why? I did not know how to do it and the kits appeared expensive. I now know the so called "tricks" and will share them with those interested (actually, there is no trick involved). If you have regular hand tools, an old gas Bar-B-Q grill to remove a low pressure regulator and hoses from (only needed for a dedicated tank - not needed for RV gas feed), and are willing to make non-reversable mods to existing parts (genset carb and exhaust manifold) it can be done with only the purchase of the demand regulator for less than $60 and couple of hose clamps, a gas ball valve and brass fittings from Home Depot or Lowe's for no more than another $20.

The engine on the genset operates off of less than 1/2 PSI at the input to the mixer (carb in gas terms). Extremely low pressure and readily available on any RV. The volume of propane used for the 200 cc engine is small enough that existing hoses and pipes on the RV are more than adequate. The generator uses about the same amount of propane when running as your gas water heater.

One suggestion I have is to have a second panel on the top which can slide out to shield the generator's power panel from the rain. This slide out panel will also help shield the generator's power panel from the sun which should help preserve it and assist with the cooling effort.

Maybe even have two small hinged panels on the slide out panel which can drop down to offer side protection from the rain. IOW, the small side panels would normally be resting flat on the top of the slide out panel. After the slide out panel is pulled out, the side panels would each be rotated 270 degrees to end up offering side protection for the generator's power panel. To even go a step further, maybe have a hinged drop down front panel too to really shield the gen's power connectors from the rain.

You have given us (me for sure) a good, compact sound proofing model to look into for our generators. Thanks!

That's what the sharing of the prototype is all about; generating additional ideas and testing them.

Skyzoomer