Quieting Yanmar L100AE

[stephenholland]

Hi,

I'm new to the forum. I noticed there are some people familiar with Yanmar L100 engines. A few weeks ago when Irene hit New England I had to run my SDMO generator straight for 50 hours. The engine ran great but it was very loud. I'm trying to figure out how to cut the noise down.  Checking the internet I found there are generators using Yanmar L100's that have a sound rating of 59db.  I realize some of this is due to the enclosure but I think these engines also have a different silencer.  When I called a local Yanmar dealer all they could suggest was a spark arrestor but I don't see what attenuation this could provide. I found the Yanmar option guide on someone's web site and it lists different silencer options but I can't tell what attenuation they provide.  Does anyone know if there is a special silencer I can use to quiet the exhaust?. Does anyone have suggestions as to anything else I can do to quiet the engine down?

Thanks so much

[vdubnut62]

My Xing Dong s1100 has a transplanted muffler from a Volvo station wagon, it does help with the noise quite a lot.
Ron

[unimog_jason]

I have the Chinese equivalent of that engine in an open frame genset and whenever I have used it I just put a couple pieces of plywood around it to help direct the sound in a different direction.

I've considered building a wood box to put over it but was concerned about impacting airflow and I also wonder that once I have put enough holes in it to allow for adequate airflow, will I have much noise reduction?

You would be amazed how much a little bit of plywood can help with the noise problem.  A three sided box like the one I attached would keep most of the weather off the genset and drop the noise a lot I think.

Jason

[deeiche]

Hi,

I'm new to the forum. I noticed there are some people familiar with Yanmar L100 engines. A few weeks ago when Irene hit New England I had to run my SDMO generator straight for 50 hours. The engine ran great but it was very loud. I'm trying to figure out how to cut the noise down. 
SNIP
Thanks so much

I have an open frame SDMO generator and it is loud.  As mentioned by others wood enclosure and better muffler would help.

[stephenholland]

Thanks for the replies. I got a voice mail from a yanmar distributer today and he confirmed there is no difference in attenuation between the different silencers. He also suggested building an enclosure as you all have.

Here is an options link which I find really interesting for the L100.

http://www.centrodiesel.com/yanmar/pdf/optionmenu.pdf

[cujet]

Some of my neighbors have built wooden boxes for portable gensets. One guy (an old German engineer) did a particularly good job. He put a small box fan in one end to move air through the box. The box is lined with insulation and the airflow and exhaust comes out a hole in the far side. He uses heavy plastic drape (like you might see on a walk in cooler in a warehouse) to "seal" the box when the fan is not running (keeps the critters out). He did not bother with a better muffler. But instead concentrated on making the box quiet.

Works very well.

[Derb]

Hi Fellas. I have an SR2 Lister which is particularly noisy. I have found that pinex softboard ceiling tiles make a very good soundproofing box. For the inlet and outlet air appertures, place the tiles at angles like a herring bone arrangement which diffuses the sound. Primitive but works. Cheers.