Generator noise

[Schmitte]

Following! Seems like it could be a big job, though.

[Rocinante]

Originally Posted by wachuko

Just in case... here is the direct link... but look at the doc for the modification needed on the base plate to accommodate these...

CENTER BOLT MOUNT - V10Z42-1010

https://www.vibrationmounts.com/cata...?q=V10Z42-1010

Very cool, thanks. I now see this detail in his second PDF. Yep, looks like quite a bit of work, but it's great to know that this helps the situation. I'd probably hire someone to do this for me, vs. getting under there myself, but one never knows.

[wachuko]

Originally Posted by Rocinante

Very cool, thanks. I now see this detail in his second PDF. Yep, looks like quite a bit of work, but it's great to know that this helps the situation. I'd probably hire someone to do this for me, vs. getting under there myself, but one never knows.

I hold the generator in place with a motorcycle jack while I remove the mounts. Easy to do if all the bolts are not rusted out... My guesstimate is that this will takes less than an hour to do...

[Rocinante]

Oh, handy, an excuse to buy another tool! May have to try it myself.

[scott.semone]

I've done a couple of things, and finally think I have my generator noise at an acceptable level; the biggest step was removing the three resting feet from the bottom of the unit (Torx screw).

Summary:

1st - Installed the silencer (-3dB) in exhaust noise
2nd - Installed rubber coated washers as suggested in an earlier thread
3rd - Install rubber floor matting,which is typically used in horse trailers between the generator and mounting bracket (big improvement)
4th - Adjusted the exhaust manifold so as to not make contact with the generator housing and exhaust pipe.
5th - Final and best improvement from a vibration noise standpoint; I removed the three resting feet from the bottom of the generator. Again, the vibration from the resting feet and the generator housing seemed to be making contact, especially if the Interstate was completely level when using the generator.

I hope this helps...

[Mr. B]

Originally Posted by wachuko

I hold the generator in place with a motorcycle jack while I remove the mounts. Easy to do if all the bolts are not rusted out... My guesstimate is that this will takes less than an hour to do...

It looks so clean underneath that you must have no mileage )))

[Seanlb]

I would strongly recommend that you not remove the ‘3 resting feet” from the genset. These are actually failsafe features that prevent the motor and alternator from separating from the base pan if the internal mounting isolators fail.

If you have noise coming from one of the 3 feet, it means that a rubber isolator is failing and deforming inside of the unit and needs to be replaced.

Removing these feet, especially when they are making contact with the base pan can lead to the motor coming loose inside of the enclosure and starting a fire, causing electrical shock, or severe damage to the unit and ultimately your coach.

[Beemerman]

On the IS 19 FB pages I posted my experience with the Noico noise pads I wrapped my gen in. I cut each in half, and carefully wrapped all the side AND top with multiple layers.
The only caution (in installation manual) is that the access panel be left open AND the bottom (cooling air exits). The install manual encourages using a 1” wrapper style noise system.......difficult on our AS IS’

Has made gen VERY quite, no cooling issuers at all........

[Mr. B]

Originally Posted by Beemerman

On the IS 19 FB pages I posted my experience with the Noico noise pads I wrapped my gen in. I cut each in half, and carefully wrapped all the side AND top with multiple layers.
The only caution (in installation manual) is that the access panel be left open AND the bottom (cooling air exits). The install manual encourages using a 1” wrapper style noise system.......difficult on our AS IS’

Has made gen VERY quite, no cooling issuers at all........

How many Mil noico pad thickness, and how many layers you put to achieve this result?

[Beemerman]

Hi folks...I used the 80 mil pads, bought the 10 sq ft package.....will buy some more...
Major PITA to install, but I cut into smaller pieces.....very sticky stuff.....then I wrapped large pieces with aluminum “100 mph” tape.

If you read the (very) techy installation manual online, Onan reccs a sound insulation procedure...

No probs to date !

[Mr. B]

Originally Posted by Beemerman

Hi folks...I used the 80 mil pads, bought the 10 sq ft package.....will buy some more...
Major PITA to install, but I cut into smaller pieces.....very sticky stuff.....then I wrapped large pieces with aluminum “100 mph” tape.

If you read the (very) techy installation manual online, Onan reccs a sound insulation procedure...

No probs to date !

Wouldn’t 315 mil be an overbuild? The link is below

https://www.amazon.com/gp/product/B0...NOZL83GP&psc=1

[parkerne]

I find the generator on my Atlas to be noisy. As mentioned in another reply, the noise is more like a metallic rattle rather than a loud exhaust.

[Martinperri]

I have 2017 Airstream, just purchased not too long ago, I was shocked at the loudness of the generator, the noise and vibration would make it impossible to sleep if this thing were running. Outside is same, I went to add a resonator on the exhaust and this too made very little difference. The cleaning of the muffler at the u clamp was a little loose so had that tightened and still loud. Just the way it is I guess, added dynamate to the sides also trying to mitigate some of the noise.

[Rocinante]

Originally Posted by Martinperri

I have 2017 Airstream, just purchased not too long ago, I was shocked at the loudness of the generator, the noise and vibration would make it impossible to sleep if this thing were running. Outside is same, I went to add a resonator on the exhaust and this too made very little difference. The cleaning of the muffler at the u clamp was a little loose so had that tightened and still loud. Just the way it is I guess, added dynamate to the sides also trying to mitigate some of the noise.

We had a similar experience with sticking a Cummins resonator on the end of our generator's exhaust pipe. The quality of the sound outside changed a little bit and seemed a tad less annoying, but the measured decibels didn't change at all. [emoji45]

[Martinperri]

I am with one of the posts that had the idea of using a jack under it especially on concrete or asphalt seems like minor pressure from underneath would help anchor it so the vibration and rattle would be less

[Seanlb]

Onan is offering a new inverter based generator that is about 1/3 as loud and will be a drop in replacement for the existing qg 2500 LP units.

Look up the Onan qg 2500i LP

All mounting points are identical, the base pan is about 10mm lower then the old model and the exhaust outlet is located a few mm down as well.

[Seanlb]

Originally Posted by Martinperri

I am with one of the posts that had the idea of using a jack under it especially on concrete or asphalt seems like minor pressure from underneath would help anchor it so the vibration and rattle would be less

We also use the motorcycle lift for our installation and service on these gensets.

There really isn’t a better solution and the price is right!

[Schmitte]

Originally Posted by Seanlb

Onan is offering a new inverter based generator that is about 1/3 as loud and will be a drop in replacement for the existing qg 2500 LP units.

Look up the Onan qg 2500i LP

All mounting points are identical, the base pan is about 10mm lower then the old model and the exhaust outlet is located a few mm down as well.

Has anyone here heard this new Onan? I would consider if I knew it was reasonably quiet.

[Seanlb]

We actually produce installation systems for the travel trailers and are going to be receiving our first 2500i this week from Cummins.

I’ll post the db difference once we test the 2 models side by side.

In the meantime, you can see a comparison video here:

https://m.youtube.com/watch?v=qbFwAL...ture=emb_title

[SWH]

Originally Posted by Schmitte

Has anyone here heard this new Onan? I would consider if I knew it was reasonably quiet.

I just confirmed that this is the model generator that is installed on our new 2021 24GT, and I can also confirm that it is indeed much quieter than the model on our 2017 Lounge.