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Author Topic: Any way to quiet a generator?  (Read 649 times)

Bill and Debbie

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Any way to quiet a generator?
« on: October 31, 2017, 10:03:02 AM »
Have a Onan 7500 Marquis Gold. Anyone make a devise for the exhaust which would quiet the sound a bit. Don't want to run a pipe to the top of the rig. Need something like a silencer....thanks.
William Bonsell
Poulsbo, WA

2010 CT Coachworks Siena 35V
1999 Cherokee Sport with Roadmaster Falcon 5250


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Re: Any way to quiet a generator?
« Reply #1 on: October 31, 2017, 10:13:04 AM »
Noise comes from both the exhaust and from engine noise. Years ago I took my Class C to a muffler shop and had them add a flat car muffler (much larger diameter pipe so back pressure wasn’t an issue). That plus some homemade baffling around the cooling grillwork (still allowing plenty of airflow) and the genset was dramatically quieter.

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Re: Any way to quiet a generator?
« Reply #2 on: October 31, 2017, 01:45:17 PM »
There are several YouTubes on modifications to reduce generator sounds. After viewing them I wasn't totally convinced that it was worth the effort. None of the ones I saw, however, did anything more than muffler modification.
Bob & Kathy
2017 F350, Diesel
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Re: Any way to quiet a generator?
« Reply #3 on: October 31, 2017, 04:08:08 PM »
My onan is smaller, but I put on one of onan's resonators.
Using a Db meter on my phone...so nothing too good....it helped overall I think but only very slightly.  negligible really.  I don't remember the numbers now.... I can probably dig them up if you really want to know.  I think I even video recorded it on my phone...but it was hard to hear anything
I'd say the affect was more of a tuning of the sound.  It might maybe be described as a bit more pleasant...but again, not significant.

I was looking at some tractor mufflers in a Tractor Supply store once, and saw one that I think would have worked better.  the onan thing is a straight flow through pipe with perforations into the outer chamber.  The muffler actual had a baffle.  I doubt if the one I was looking at would give it too much back pressure....possibility I suppose, but I seriously doubt it...
Brad (DW + 3 kids)
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Charlie 5320

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Re: Any way to quiet a generator?
« Reply #4 on: October 31, 2017, 06:41:38 PM »
My onan Marquis Gold 5500 is pretty quiet compared to other onans I've had.  My generac generators all have been pretty quiet too. I did buy a muffler for a garden tractor on Ebay for the onan 4000 that was in my Daybreak. Most of the noise was from the generator itself not the exhaust. The muffler I bought had a larger diameter pipe so I had to find an adapter to make it work.
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Re: Any way to quiet a generator?
« Reply #5 on: November 01, 2017, 06:30:51 AM »
With my Onan 4k genny, most of the noise seems to come from the engine and not the exhaust.
I know you believe you understand what you think I said,
But I am not sure you realize what you heard is not what I meant

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Re: Any way to quiet a generator?
« Reply #6 on: November 01, 2017, 07:19:19 AM »
I know you said you don't want to run a pipe to the roof, but I think a Gen-turi type of setup is likely about the most effective noise and exhaust fume reduction method available at a reasonable cost. I have seen a Gen-turi type pipe setup permanently installed at the rear of a coach with the generator installed at the rear corner.
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John From Detroit

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Re: Any way to quiet a generator?
« Reply #7 on: November 02, 2017, 07:27:02 AM »
I have an 5500 and I can barley hear it. (of course mine is gas, not diesel, that may make a difference)

I Strongly suggest the Gen-Turi for all RV generators.  It does not (As near as I can tell) Quiet it as much as change it (Deeper, more throaty sound. lower frequency/tone/note) but then that is not what is designed for.

When my coach was new it took 2 hours for the Generator to set off the CO alarm

I ran it 4 hours this AM with narry a beep.. THe Gen-Turi takes the fumes UP, UP UP and away.

In a campground (Boondock) situtation the neighbor's Generator fired off my CO alarm.

Not so if neighbor has the Gen-Turi.

I strongly recommend it.
Nothing adds excitement like something that is none of your business
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