To all:

Noise is such a simple and inexpensive problem to deal with, I am suprised to find several postings complaining about it.

The majority of the noise from gas run generators is made by the exhaust of the engine. The cheapest way to resolve that is with a multi-muffler manifold or attaching a large car muffler to it.

Get some black iron pipe which is the same diameter as your engine muffler that screws into the engine exhaust port. To that, install a black iron tee with the center section of the tee the same size as the pipe thread coming out of the engine and the two opposing fittings at least one size larger. Run a pipe from the end of each opposing tee to another tee where the opposing tee connections are the same diameter. The center connection at those tee fittings should be the same size as the muffler you are going to attach to it. Run another pipe from each of those tees to a 90 degree reducing elbow that has the same size pipe diameter at one end and the muffler pipes diameter at the other end. Make sure that the pipes running between the tees and elbows are long enough to allow muffler installation at each point. Attach (4) mufflers and listen to it purr all day long. For an automotive muffler you only need to run pipes, & adapters to clear the generator before clamping the muffler.

The biggest thing to contend with will be the weight this modification puts on the engine exhaust port. If the engine is solidly mounted, just run (2) support bars from a couple of points on the generator chassis meeting at a "U" shaped support at the end of the newly installed manifold. Make the manifold end of the support "U" or "V" shaped so that the manifold just lays on it and do not use any clamps at that end so that the manifold can flex freely when heated by the exhaust.

If the engine is mounted on springs or rubber vibration isolators, you will have to attach a support to the top part of (2) of the engines mounting base bolts so that the support travels with the engine and does not stress the manifold or the engines exhaust port. The (2) support bars should meet at a "U" or "V" fitting supporting the manifold with no clamps so that the manifold can flex freely when heat from the exhaust causes expansion.

Good luck!

Bountyhunter