3000W Chinese Gensets Info.

Old & Slow wrote:
John, Prof' likes to call you Dr. Austin. For this post I'll just go with John. Just not Dear John;)

Here is what I experienced with relocating the muffler out of the box. I was never able to overcome the heat of the manifold/exhaust. I think you will find 400 plus degrees in the pipe for some distance. Muffler wrap 'might' do the trick to lower this temp. Using a 400 plus degree boiler wrap I was unable to touch the insulation cover. At that point, I decided I would never relocate the muffler. If you find true binefit when the job is completed, that will be needed info' for others wanting to construct an ideal, sound lowering box. I continue to promote the use of the 1/2" 4' x 8' sheets of sound board (the black stuff) from either Lowe's or HD. The board I used is stamped (from HD) 23 STC. Looks like celotex. What I hold to is it's more important to absorb the noise of the gen, not just block or stop sound transmission. I would like to know if you have an opinion of any binifit by using the Hardi product as a first layer. Anyway I'm down to being able to lower the noise from my Champ by 15 dBA with using only the 1/2" sound board and off- setting all air intake and exhaust. No direct 'open' view of the gen. And placing the gen on carpet. The Rubber mating Prof' uses would be perfered. This thread has been a great learning experience which continues. Kidos on your project. Carry on.

Floyd,
As you know, I wrapped the very short header, muffler, and exhaust pipe with header wrap. It controlled heat to the point you could at least momentarily touch the wrap without being burned. I was just "guessing" that if I moved the muffler out of the enclosure, the rather slender header would have so much less surface area traversing the enclosure versus the existing exhaust system that there would be less radiated heat (it certainly will allow large air gaps, at least!). I was planning to try the header wrap again, then perhaps a layer of fiberglass to provide some air gap, then maybe use some heat shield material (same stuff used to protect floorboards from catalytic converter) my brother gave me to enclose that.

I thought that then I might be able to enclose the bottom of the genset - probably use a heavy rubber mat inside of sheetmetal on the bottom. I think the Hardiebacker works well on the flat side panels and top, especially since it is glued to the foam lining of my metal panels and can "float" so the mass doesn't transmit sound/vibration to the sheetmetal. I already have designed my present generator head air intake and genset ventilation (both forced/fan driven) ducts to force any sound through right-angle turns. That would just leave fabrication of a passive intake duct for cooling and carb air, and a passive duct for the generator head cooling air exhaust. I'll offset those, too, somehow!

Regards,
John