Silencing the air cooled engine

[One Tough Pressure 580]

I was recently shutdown by the County Sheriff for a noise complaint. I asked the deputy if it was the water whoosh or the engine noise and he confirmed the engine. This is an account that I have had for nearly two years and always done at night, and now it is an after 7A.M. on Saturday deal.

Today was the first day time cleaning and I am not happy at all. The place is a mad house. Starbucks is across the lot in an adjacent center and all the customers park on my lot which is a serious problem for me. I had to abandon ship and will be back tomorrow for the other half.

So aside from dropping the account, what can be done to silence a Honda 20 hp and an Onan 14 hp? I do not beleive a larger muffler would do the trick as the noise is in the high rpm of the air cooled engines.

If I were to build insulated panels around the machines or go to an enclosed trailer that is closed up any answer to my prayers?

I know they need to be ventilated and that would be done with 12 volt radiator fans.

I used to have another guy help me at this place and we had 2 20 hp Hondas & 2 generators going with no problem.

[Beth n Rod 1,279]

Show your client the sheriffs shut down order and the time that you are allowed to operate and renegotiate the contract to account for the extra time and so forth.

Trying to do anything other than putting the unit(s) into an enclosed trailer will obstruct the airflow which you are already aware is necessary to keep the engine cool.

One quick thought is to contact the mfr and see if there is another muffler available to help quiet your unit. That is the most I can think you would be able to do without serious modifications.

Rod!~

[charlie 14]

You might want to get a noise permit from your city haul which will allow you run your machine a certain time and noise decimal limit.

Charlie

[Christopher 102]

There are 3 guys out on the bulletin boards that have had auto mufflers installed onto their rigs and they have told me that it is extremely quiet now. One told me that he had to to get a huge Homeowners Association account which was several hundred houses and nobody wanted loud machines in there. Another was just tired of the loud noise and the last told me that the neighbors would always complain when he worked but I guess maybe everyone does not hear the guys with chainsaws, weedeaters, leaf blowers or loud motorcycles. I am looking into doing the same thing with my 20 hp Briggs on my pressurewasher so it is not as loud as I also do some accounts at night that are across the fence from houses. Luckily nobody has complained yet. I was wondering: If you are cleaning a business in a Business Zoned area would there not be allocations for noise for all hours of the night since it is a business? The 24 hour fast food places or stores-- a lot of loud cars and motorcycles go there at all hours but do people call the police for the loud noise? No. Sometimes it is not fair. Whenever I get the Auto muffler on my engine I will post a picture but it will be a while.

[JimCrossley 14]

I do a lot of work for condo and homeowner associations. I had a auto muffler put on to one of my machines a few years back and it really makes the noise level come way, way down. The stock black muffler cover was removed and bent tail pipe was welded to the factor muffler outlet. The muffler is supported by a bracket that is welded to the belt housing of the indirect drive. I can still pop open the cover to change belts.

The only issue I have had is that I need to turn down the power on the machine for about 60 seconds prior to turning off the machine. This is to remove the gases inside the muffler so I do not get a back fire (very big boom).

Every one who sees and hears the machine agrees that while it is a little funny looking it is very quiet.

I hope this helps you out a little.

[VanDiesel99 14]

That would be nice to have that loudness muffled, I have a 25hp that I would like to do that to. I wonder if you can rig it where it won't backfire. I also wonder if it is hard on the engine in any way.

[One Tough Pressure 580]

A larger muffler is in no way damaging to an engine. I will have to try the muffler, but I am fairly sure that the real noise is the high rpm.

I called the City on this one and the rules are 7Am to 7Pm Mon-Sat. No work at all on Sunday. (Icheated today and worked anyway) Because it is so close to Residential, they do not make any exceptions. I talked to a few store owners in this center and they all said that one guy who lives behind the building has been a complainer since they started building it. He calls the City on everything.

The guy sleeps with his window open, and told the Sheriff that if he were to close his window, he probably would not be able to hear the noise, but that he did not feel like closing his window.

I was there at 6 AM yesterday, to get everything setup, and prespray. I then sat around waiting for 7Am and turned the key right at 7. I started on the end that this guy lives on just to rattle his windows. Maybe I should take the muffler off just for him. When he gets a taste of that, he will beg for the night crew to come back.

[VanDiesel99 14]

What can be done about that very undesirable backfire?

[4running 14]

I used to do exhaust on vehicles,

I would try to use nothing larger than a 1-7/8 " pipe, and if you have too, use a resonator or "Pre" muffler before the muffler, this will even out the "pulses" from the exhaust making it seem quieter as well. Also, the lower to the ground you put the outlet (Best to cut it to face toward the ground) the quieter it will seem.

Another tip is that the shorter the exhaust system in length the louder it will be.

Beware of a muffler with too large of a chamber for the flow of these small engines as a chamber that is too large makes the exhaust sound hollow and tinny and makes it seems louder as well. I bet you could make one of these REAL quiet if done properly.

[HotShot 34]

funny, we put certain mufflers on our vehicles to make them rumble (MagnaFlow, Flowmaster, Borla, etc....) but we put them on pw to make them quiet.

I also had the muffler shop here in town give me a quote on doing that to mine and he said that he has done it before and it DOES work!!! For about a 100 bucks, it's prolly worth a shot.

Alan, I think what was loud on your rig was that generator. I don't know if it would be powerful enough, I think it would though, maybe look into getting a Honda 3000 es. You can hardly hear those things run.....

[4running 14]

What can be done about that very undesirable backfire?

I would use a diameter that is more appropriate, and a muffler with a smaller chamber or a muffler with more packing versus just baffles.

Kyle

[Washaway 64]

....

I was there at 6 AM yesterday, to get everything setup, and prespray. I then sat around waiting for 7Am and turned the key right at 7. I started on the end that this guy lives on just to rattle his windows. Maybe I should take the muffler off just for him. When he gets a taste of that, he will beg for the night crew to come back.

I feel for you. Often I've wondered how long before the cops show up and shut me down.

I strongly believe that it would be worthwile to have 4 or 5 machines (without mufflers) running for a good hour every day for a week, right @ 7am. I'm sure he'd have a fit and would get the message.

[john@AEC 37]

Hi Guys

I've had a few locals ask me to turn the pump off over the years, once was at 5 am on Sunday LOL!!!! The most recent has been at about 1 am on a week day in an area that was commercial/industrial, but as it is near the CBD has become residential.

I'm glad to read that the pump can be made quieter with a new exhaust, may be a motor bike system would be better as they have a lot of packing and are designed for small single/twin cylinders?

Or next time I'll just say "At least it's not a two stroke!!!"

Cheers