What resources to look at for building a quiet generator compartment?

[belfert]

Justin from Wrico drew me up a possible layout for how to position the generator in the space I have.  He kept telling me there are too many variables to suggest a good design for a sound box for me.  I talked to Dick one day and Dick said he was not familiar with Dina coaches, but I sent him pictures and he promised to call me back which never happened.  Dick hasn't been in the office much due to COVID so getting in touch with him is tough.  The day I talked to Dick he was only there because Justin happened to be taking a day off.

I have a friend who is an engineer and works with a lot of other engineers.  I am trying to get in touch with him to see if he can help with my design.  He goes on trips in my bus so he has a vested interest in a quiet generator.

[Utahclaimjumper]

 Red Rider has a Wrico AIR COOLED diesel genny (6500 )  that's exeptionally quiet considering it's in an open box at the bottom and one side. And an all electric coach.>>>Dan

[bobofthenorth]

There's 3 concepts to keep in mind for a successful design - sound deadening, vibration isolation and air flow. The low frequencies take heavy material to absorb their energy. The mounting has to isolate vibration or you will feel the sound as much as hear it. And as has already been extensively discussed you need to baffle the airflow while maintaining cooling and combustion air for the genset. I saw a Wrico installation many years ago now. You literally could barely tell it was running standing next to the coach with the gennie doors closed. This is not a place to re-invent the wheel - find something that is working and copy it.

[belfert]

What I am planning to do is call and talk to Dick tomorrow, or more likely, talk to Justin at Wrico.

How loud is the squirrel cage blower for the radiator?  Do I have to worry about noise from the radiator blower if remotely mounted?

[windtrader]

Listen to Justin and others here trying to guide you to get what you want. You will NOT do this well as DIY. Talk to your engineer friends but unless they are trained in acoustic abatement specifically, then you are to going to build anything near an engineered design.


Even if you find someone who says they know about managing sound, that's not enough as someone may manage sound in an auditorium, or theater, etc. The physics are the same and they share materials as well. It is the application that makes this so tough. Every dimension is precisely calculated to properly deflect or absorb or redirect sound energy. Plus a dozen other calculations that have to be just right. :ice Bob says, all this has to be done for each category involved in sound management. It is very much a specialized profession. This is all if you want it done well. And that means the proper materials are $$$

[belfert]

I am trying to see if my engineer friend knows anyone that is specifically an acoustic/sound engineer.

[6805eagleguy]

I would advise having someone at wrico draw something for you. it can be a trick to fit everything in how you want it. I also have a 12.5k wrico. Just put 110 hours on it. My generator has the radiator in the same compartment. it takes the middle of the front bay, with enough room on the drivers side for my propane tanks. My generator compartment is built out of 18 ga. steel, and sealed, the entire inside is covered with the sound deadening i bought from wrico. I dont think it would have to be a steel enclosure, but that is what i did. From the outside of the bus the generator is way quieter then a honda. you can barely hear it from 30 feet away. of course the loudest part is the exhaust. A exhaust stack would make it a lot quieter for dry camping. I also decided to not have any batteries, inverter, there are no low voltage house systems. (except for propane water heater which is run off converter) Diesel is not that expensive. We also decided that we bought the best genset money could buy and we plan to use it. Which means running all the time we're on the road.

How my compartment is set up.

I have the squirrel cage fan mounted on the outside of compartment, pressurizing compartment. It pulls from a large hole in the floor of the bay, right behind the bulkhead, in between the front tires. Blowing air across engine and thru radiator. From radiator it goes thru the floor, at the back of the bay, 5 feet from intake. have not had any issues. hottest we've driven in was 90 degree weather. The underside of the bus is extremely pressurized right there. (thats what i have found.)

as i said, outside sound level is extremly low. right now, it is noticeable from the inside, but i am going to add some more insulation on the top of the compartment. we will see if that helps.

HTH   mason

[belfert]

Listen to Justin and others here trying to guide you to get what you want. You will NOT do this well as DIY. Talk to your engineer friends but

Justin from Wrico has already stated he can't help with a design.  It seems like you and most everyone else are stating this is not a DIY task.

I think what I am going to do is drain my savings and order a Cummins Quiet Diesel 12.5KW generator so I don't have to worry about building an enclosure for my Wrico generator.  Part of why I didn't go with Cummins in the first place is the expensive electronics if/when they fail.  The Cummins "Quiet" Diesel seems pretty loud to me at 70 DB.  It is twice as loud as a Honda generator.

I'll have more money in my generator than some people have into their entire bus.

[6805eagleguy]

Huh. Just when I try to help.

[6805eagleguy]

I'm trying to find some pics of mine, they were on my old phone which got destroyed...

[belfert]

Huh. Just when I try to help.

I wrote my reply before I saw your post.

[belfert]

I would like to rent a light tower for a day to look at the soundproofing and see how loud it is, but not sure my minivan could tow it.  Spring load restrictions are in effect for the next six to eight weeks so I can't use the bus right now.

[chessie4905]

you can learn a lot from scrutiny of a Prevost Marathon. Anyone near by? Or one for sale?

[6805eagleguy]

I only have one pic tonight, and that's without a door on the compartment. It still allows a general idea, tho

[6805eagleguy]

I do not think light towers are the quietest, but I bet you could go to  a rental place, have them show you one and start it. It would give you some sort of idea