Onan noise

[VMProfBob]

So I have a 2020 Jayco Melbourne 24L. While camping I needed to run the generator. I fired up the built in Onan and thought, dang that’s loud. Compared to portable inverter generators, the onboard generator is obnoxious. I looked into the cabinet where the unit is installed to see if there was any way to add sound dampening material. Didn’t look like anything added to the walls would be of benefit since the generator has no enclosure underneath.

I know there are campgrounds where decibels are controlled. Aside from buying an inverter generator, I’m looking to figure out how to make the unit tolerable. Muffler, sound dampening, etc.

Has anyone successfully made the generator quieter? Suggestions?

[CAG]

The 5500 on my toyhauler was pretty quiet. The 4000 on this Greyhawk is loud and annoying.



You really cannot put a muffler on it without adding back pressure which is not good. More insulation around it, which then adds to the heat. Pretty much I think we are stuck with what it is.

[craigav]

I think if a company was to make an inverter style and quiet generator that was a drop-in replacement for the Onan 4000 that the company would make a lot of money.

With that, I think the 4000's sound louder inside the RV (Class C) because they are connected to the frame which transmits a lot of sound and vibration. Perhaps different mounts like on springs or foam would help. Overall though, they aren't super loud 50' away from the RV, least not compared to some industrial generators I have heard including one I own but don't use for RVing.

Another outside the box thought is if the generator exhaust was routed to the RV's exhaust in front of the muffler, being that the RV's V10 exhaust system would be very large for a 4000 generator, I suspect the back pressure would be low enough but whether or not it would be much quieter though... I suspect some, not enough for all the trouble.
~CA

[pconroy]

I recall reading the National Park's upper limit is 64 dB. The Onan 4000 Microquiet is rated for - yep - 64 dB.


There's no incentive for Onan to change. And none for the typical RV maker.

[Stavman]

For longer running, I'm a football junkie, I run my Honda 2000 genny

Works amazing for everything except the AC. 5-6hrs on 1.5g, and very very quiet

The onan 4000 is far from quiet, but also normal for what it is.