Community Forums

Wmjp · 09-07-2019, 09:22 PM

I’m going to try some sound deadening material and possibly a resonator as well. Thanks for the great advice. I think most of the noise is air from the generator cooling fan. I’m contemplating mounting a automotive type elec radiator fan on the inside of gen compartment door. I’ve had some problems with too much heat here in Florida quite a few times. Any thoughts on this or comments. Great forum and great people... just sounded like POTUS didn’t I.

avfordguy · 09-07-2019, 09:47 PM

https://www.irv2.com/forums/f87/loud-generator-415092.html

If onan 4k shuts down in hot weather (95+degrees) replace fuel pump first. South texas heat kills original onan pumps, got a direct replacement from Amazon, aitex, no more shut down.

hdzcar · 09-08-2019, 04:56 AM

I recently tried the resonator on the 4000 and it made no difference and I sent it back.
Changing the fuel pump is PIA. I added some fuel line and moved the fuel pump to the frame rail outside of the generator. Not sure why Onan thought putting it under the circuit board was a good idea. My generator only had less than 20hrs on it but was shutting down after a few hours in 90 plus degree weather.

1st-tt2018 · 09-08-2019, 05:28 AM

There os another thread about onans that the poster had a vent cut in to the hatch door and fabricated a "cold air intake" for the genny to solve the problem. A fan would definitely help. If you can get a remote thermometer in there to monitor temps and operate the fan for you

sibe · 09-08-2019, 03:54 PM

I responded to that post listed, my genny install is very open ... under rear bedroom..

I have posted the db readings somewhere.. but I found the resonator to help for 2 db with a tailpipe, this was after I added sound deading material to under the bedroom.. That was good for alteast 5-6 db avg.. then the resonator made a slight change.. I could not get a good reading in resonator from all the background AIR noise,,

I may add some fiberglass duct board to baffle the noise underneath.. the noisiest area on mine is outside on the opposite side of the genny mount.. it must echo off the ground...

Wmjp · 09-08-2019, 08:23 PM

I’m thinking about just wiring the fan up so it starts when the generator starts. Probably having a cutoff switch makes sense. I saw the post about installing a duct on the air intake from the door. Pretty clever. My logic is lots of cool air for the entire unit might extend the life of all the components. Thanks for your input, I will keep posting as this progresses.

dirkexc · 09-08-2019, 09:10 PM

I have also been on a quest to quiet down my 4000 I heard the venturi set up helps, I have not put the parts together for this yet. I did try adding a muffler from a Honda 450X dirt bike. This muffler really quiets down a dirt bike but it had very little effect on reducing the noise from the generator. After I put the muffler on it became quite clear the noise was coming from the generator it self.
One comment I read was to place a piece of carpet on the ground under the generator and hang another piece of carpet from the edge of the MH to the ground.

sibe · 09-09-2019, 10:04 AM

Quote:

Originally Posted by dirkexc

I have also been on a quest to quiet down my 4000 I heard the venturi set up helps, I have not put the parts together for this yet. I did try adding a muffler from a Honda 450X dirt bike. This muffler really quiets down a dirt bike but it had very little effect on reducing the noise from the generator. After I put the muffler on it became quite clear the noise was coming from the generator it self.
One comment I read was to place a piece of carpet on the ground under the generator and hang another piece of carpet from the edge of the MH to the ground.

yep.. agree, I was going to try to hang that brush sweep stuff used in the back to stop stones etc...

I should slow down the sound

THenne1713 · 09-09-2019, 09:40 PM

On my 99GS Conquest 6266, GEN is on driver's rear, the old Onan BGE sucks in cool air across the fuel pump on (right rear), and blows HOT out (left) front bottom; so in fact, if traveling, hot air is recirculated w/ air intake. I know the Onan KY moved pump to the left, but guessing that still on the air intake, before the air is blown across the cylinder heads? Even on the old BGE, a new fuel pump cured my shut-down issues.

Ron Dittmer · 09-09-2019, 11:51 PM

To quiet the worst of the noise from our 4000 Onan, I lean our 2'x4' folding table against the side of the motor home there.

A large plush carpet under the Onan would also help with reflected noise off the parking pad but I don't carry such a thing.

THenne1713 · 09-10-2019, 11:49 PM

(From my memory/ experience), resonators were originated/ used to ADD Noise/ tone (vs quiet, factory muffler)... e.g. Muscle/ horsepower, and yet stay Legal on noise limits?... usually replaced a muffler, NOT in addition to a muffler?????? Spark arrestor and Baffles were also commonly removed from chainsaws and Motorcycles to increase horsepower (or perception of) and add "exhaust tone"... so for GENS to be quieter, replace missing spark arrestors and add/ replace "baffles", after checking/ repairing any exhaust leaks?

THenne1713 · 09-11-2019, 12:05 AM

(One other thought on COOLING) always a good idea to pull some sheet metal to INSPECT and make sure COOLING AIR is NOT blocked by old wasp nests, mouse/ rat nests, or worse, dead rodents?