Generator Noise

[TQUIN45]

In the past several months I have had to take interest in Generator noise. Back in Aug my wife and I traveled from Mass. to the West coast and did a bunch of National parks. We were asked to shut down our generator because it was too noisy. Our generator is a Cummins Onan RV QD 3200 Diesel. It's output is 3200 watts. Winnebago uses these in their VIEW model. The Cummins noise specification is the noise will be less than 68 dBA at 10 ft and 1/2 load. I have measured (with sound power meter) the noise at 78 dBA which is 10X louder than spec. I spoke to other RV Views owners and theirs are also very noisy. At this point Winnebago will do nothing to help but Cummins has shown interest in helping. The other issue for people to be aware of the location of the generator exhaust- just behind the rear wheel directly under the awning and below the rear bedroom window. Being under the awning goes against all of Winnebagos safety notes- again they will not help by changing the location possibly out the rear of the coach. If anyone has any questions please ask.
Note- Honda and Yamaha generators are usually below 58 dBA noise- worth noting if possibly going to purchase one.

In my previous RV- a Winnebago Vectra our 8000 watt diesel generator was much quiter than the QD 3200 watt. At 10 ft you could barely hear it.








a

[Reddog1]

Duplicate Threads not allowed, see same Thread in Class C.

Wayne
Moderator

[Handbasket]

I take it that you have a View class C, but have inadvertently posted in the 'truck camper' forum?

Most C's have the generator installation done very poorly by the RV maker. You can almost surely improve on it. Get a copy of Onan's _installation_ manual for your model.

It'll show what clearances Onan says must be maintained around the generator box. If there's room in the compartment, buy a big sheet of foil-faced rigid fiberglass insulation (furnace supply house) in 1" or greater thickness. Line as much of the compartment as possible.

I'm assuming (maybe wrongly) that your Onan sits on a couple of steel bars welded to the frame. Remove the mounting bolts. Lift the Onan. Cut some big hard rubber washers at least .2" (2/10") thick. Place around the mounting holes. Buy 1/4" longer bolts. Install bolts with blue Loctite, and do _not_ torque them tightly, just snug.

Again assuming, since I'm not familiar with the QD's: Onan uses a system of vibration isolation on their small gas & LP generators. The outer tailpipe has to be free to shake, or it partly defeats this system.

Again from the small gas Onans, there is an optional resonator for the exhaust. It doesn't work miracles, but it helps. Dunno if one is made for the QD's.

With these steps and a SuperTrapp spark arrestor, my 2800 runs at 57-58 dbA at 23' (7 meters) at any load. I can stand right at the exhaust and carry on a conversation with a friend standing on the other side without raising our voices.

Jim, "I've learned so much from my mistakes, I think I'll make some more."