genset sound sheild

[septembre]

Did somebody ever soundproof their genset and if so what they use.

[Edelweiss]

My Onan 7.5 KW came with a sound deading case from Onan.* The case is made of fiberglass panels and a two piece top which are lined with a hard fiberglass insulation pads.* The panels and top are held in place by sheet metal screws.**

Looks like would be quite a job to construct one from scratch.* Does your generator manufacture offer or recommend a sound sheild?

*Larry B.*

[BruceK]

Edelweiss wrote:
My Onan 7.5 KW came with a sound deading case from Onan.* The case is made of fiberglass panels and a two piece top which are lined with a hard fiberglass insulation pads.* The panels and top are held in place by sheet metal screws.

*Standard Onan issue, like mine. I have priced gensets online, most offer a sound shield surround option.They need to fit well. Half the noise comes from water and exhaust gas hitting the water together,you can get gas/water separators which make a genset in an anchorage more neighbourly. BruceK

[Marin]

septembre wrote:
Did somebody ever soundproof their genset and if so what they use.

The Onan Jurrasic Series MDJE 7.5kw generator that came with our boat has an Onan*sound shield.* Back then they were made of sheet aluminum side panels with a one-piece*molded fiberglass top.* The insides of the panels and top are lined with a fuzzy, woven*matt material (not foam).* One of the front panels is held on with Dzus fasteners to make it easy to remove for checking oil, belts, etc.* The rest of the panels and top are held in place with stainless sheet metal screws and washers.

Despite its mostly metal construction and minimal soundproofing material the shield makes a major difference in the sound transmitted to the inside of the boat.


-- Edited by Marin on Thursday 16th of February 2012 01:30:00 AM

[bobofthenorth]

Whatever you do for a sound shield think through how you are going to service the gennie once the shield is installed.* Our Onan has the same prehistoric shield that Marin refers to and it was clearly designed by an engineer.* Service is more or less impossible without removing several screws.* You can check the oil without disassembling the shield but forget about the zincs or lubing the starter.*

[Larry M]

We have a Northern Lights generator with their sound shield. The NL has all it's service points on one side which is good.* If you need to change the exhaust elbow, water pump, or adjust the valves you have to remove additional panels which is an installation consideration.** The sound shield*reduces the interior noise*significantly.

[Jay N]

We have a Northern Lights 5KW with factory*sound shield installed in a crowded lazarette.* The deck over the unit is fiberglass/balsa core and teak decking.

As an experiment, I took decibel measurements with the sound shield in place, and with it removed.* In our installation, the difference was 1 db(a) louder without the shield.

Even though most service points are available on one side of the generator, the shield makes access very difficult, and in fact blocks access to the fresh water tank valves*in addition to making servicing the steering system very difficult.

So, have removed the sound shield and will install 1/2" plywood faced with foam/barrier soundproofing on three sides of the generator.* Access to the generator and non-generator systems will be drastically improved, I don't anticipate any meaningful increase in sound level.

[Keith]

My Westerbeke has a very effective and well designed shield. All of the panels are held in place by two thumbscrews and easy to remove for service. Regular maintenance can be done by removing just one side panel.

[JD]

Keith wrote:
My Westerbeke has a very effective and well designed shield. All of the panels are held in place by two thumbscrews and easy to remove for service. Regular maintenance can be done by removing just one side panel.

*Ours is a Kohler and it is much the same way. Very quite. Easy access on one side.