Muffler ideas to quiet generator?

[Fred404]

I bought the Techcumseh (part 37350) quiet 'lo tone' muffler to quiet down the Tecumseh hm100 engine on my 'Powerback 5250' generator. Well worth the money! It's about half as noisy as before, going from "I'd rather not run it since it's sooo noisy" to being tolerable (for use during power outages at home). The engine came with a cheap 'square can' muffler, like for a push mower. This is much better.

 

[jinman]

That reminds me of what I did once on a Whitco Pressure Washer with a 16 hp twin cylinder Onan. That little muffler was so loud that it made standing near the washer almost intolerable. I got a manifold built by a muffler shop that fed into a normal auto muffler. It made it much more quiet, but to add a finishing touch, I installed an old Volkswagen muffler baffle pipe on the outlet of the muffler. It made it amazingly quieter, but it kinda sounded like a Volkswagen when I revved up the engine.

 

[sandman2234]

Mufflers can only do so much, at which point the engine mechanical noise takes over and keeps it from being completely quiet. Sound barrier enclosures are the next step, or some sort of sound barrier to lower/limit the noise of the engine once the exhaust noise is reduced. Due to changing portability of mobile generators and cooling issues that have to be addressed, most people just do the exhaust and live with the rest.
David from jax

 

[Egon]

For stationary operation & CHEAP:

Two metal 45 gal. ??? barrels hooked up in series and connected to the exhaust with a flexible tube will do wonders. Throw some insulation around the barrels and it even gets better.

 

[Skyco]

Better yet fill one of the barrels with water!

 

[grsthegreat]

Ive had an automotive muffler on my Onan genset for a LONG time. Works GREAT. very quiet.

Ive heard that some smaller generators may have a problem with a full out muffler, causes too much back pressure on the system. Not sure how true that is. I know mine is a generator like they use in large motor homes, and those are piped thru mufflers so i didnt worry.

 

[billybobjimmyjoejack]

I made a muffler using an oval 16ga. steel tube and welded ends onto it with a straight outlet pipe and an inlet pipe that was bent at 90 deg. with a flange welded on that bolted to the B & S engine on my generator.
I extended the two pipes into the oval tube about 2/3 of the way end to end and offset them at the same time in the oval. I also cut slots in the portion of the tube that is inside of the oval.
It took a little while to design and fabricate, but it was an easy project and it really works well, reduced exhaust noise by about 50%.

 

[kenmac]

Ive heard that some smaller generators may have a problem with a full out muffler, causes too much back pressure on the system. Not sure how true that is.

Years ago,I was told by B&S when I went in search of a muffler for a generator engine. It was a B&S engine with the round muffler that scrwed into the head

 

[ray66v]

A bigger muffler can help some, if it has a really tiny .99 muffler on it. But, Sandman is right, your going to find that most of the noise on a generator like that, is not coming from the muffler.

If it was not designed to be quiet, your not going to make it quiet.

My Generac already had a decent, low tone muffler on it. But, I went to great lengths anyway to install an automotive muffler on it, and it hardly made any difference. In fact, I went back to the original one.

Building a sound absorbing enclosure for it, is the only option, and then your going to have to be careful not to overheat it.

If you really want a quiet generator, you need to buy a quiet generator.

I stood next to a large trailer mounted generator on a movie set once, and you could barely tell it was running. That was amazing engineering.

 

[jonyyuma]

You cannot hear the new "Quiet " gen sets running, unless near full bore?The baffled air flow to radiator and the padded cases, have teamed up with good exhaust. I always liked Onan Mh installations for quiet?