generator noise

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henryj2

Veteran Member
Joined
Oct 24, 2014
Messages
81
Location
USA
Vessel Name
Curly Sez Wow
Vessel Make
Gulf Star
Spent last night aboard our Gulf Star anchored in San Diego Mission Bay. Have not previously used the the generator (Onan 14 kw) much but last night used it for cooking and a little tv and a little was correct. Plenty of racket making tv watching difficult and requiring the sound be set on high. Any ideas about sound proofing the generator room without interfering with ventilation and other ways to cut down the noise or is it just the nature of the beast? All suggestions appreciated.
 
Is the generator in a sound shield?
 
What exact gennie is it? Post a photo, best, or at least exact model MDxx...

I've solved a bunch of gennie noise issues and rarely was that by putting a sound box on.
 
Thanks for the interest. The generator is a Onan MDJF. I don't know what a sound shield is but the generator is accessed by pulling out the steps from the salon to the galley. Generator to the starboard, batteries to the port.
 
A sound shield is a "box" that is sound insulated in which the generator is encased.
 
Onan supplied optional sound shields for most of their generator models. We have an Onan MDJE and it is in a sound shield. We removed the shield and took it home awhile back so the electrical shop could access the generator's starter and remove it for rebuilding. We have yet to replace the sound shield because we're changing out the sight tubes on the fuel tanks and having the shield gone gives better access.

I can tell you that while the presence or absence of the shield makes no difference to the generator sound outside the boat (not much more than the splashing of the exhaust water) it does make a major difference in the sound level inside the boat.

The old Onans are not quiet and never will be, but a proper sound shield does make a difference.
 
I run the TV on a little inverter via a cigarette lighter plug, no genset needed, but cooking is harder to power. Yours is a large one at 14KW, mine is 6.5 in a shield and I struggle to hear it inside. I think Marin`s is similar in Kw, maybe the sheer size of yours is an issue. How many cylinders on the engine?
A sound shield box should help, Onan may have one to suit.
How about your engine mounts, are they ok? Is there an issue with any sound reducing part, muffler/exhaust system, even a leak?
 
If the sound shield won't fit for some reason, there is also soundproofing material you can adhere right to the walls. For it to be effective you'll have to do every surface including the floor.
 
lots of good ideas. Will follow up. Thanks
 
I ditched a 7.5 kW Onan in a sound shield and have no regrets at all.

An inverter and a few extra batteries (if required) is a good alternative to running a generator for very light loads. If an electric cooktop or aircon is part of the boat then a largish gennie is needed on board, otherwise they really are are a complete waste of space. Silence is wonderful too!

Even when I was in the PNW, the solar panels put out quite decent power.
 
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Windmill- Great product, I took a peek at their site but all I found for a price was a "Send for Quote".box. Any ideal what this goes for in single thickness sq. foot?

Al
 
For minor loads the Honda 2000W unit might be the simplest answer.
 
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