1999 Popular Generator Exhauxt Pipe

[rowiebowie]

They make a resonator that while the dB level doesn't go down, the harsher high pitched notes do making it seem less noisy. Unfortunately, they don't get quieter and don't meet current rules for national forests.

There is a screen in the generator tail pipe right as it comes out of the generator muffler that is the approved spark-arrestor. From my personal experience, you are right about the change in sound provided by the resonator. However, I don't see how adding the resonator aft of the spark-arrestor would violate the national forest rules.

 

[inforiculturist]

That's the first I've heard of this, documentation, links, cites?

You're right; I was a little lazy but I'd seen this on several other sites and then there was this post from a month ago here. That and the next post includes the utube video giving you an idea of the change of what the Microlite 2800 generator sounds like with and without the resonator attached. That thread has a generally good overview of other info I've seen in the wild about mufflers, resonators, and other quieting aspects for these generators. Most people seem to agree the resonator (about $35-40) is more pleasant than without.

Onan 0155-2449 Generator Exhaust Resonator

Part of me wants just to add another muffler, which I'm told is a bad idea (and research seems to agree), or do a DIY Gen-Turi setup, or replace with enough batteries to run the AC (as I live in the warm south). Or a newer quieter generator that fits the same space (mine is internal).

I just had my generator fully serviced (total of 83 hours after almost 25 years reflects neglect) with a new carb and will drop it back into my RV this weekend. I'm planning on installing some MLV sound proofing which is supposed to help reduce internal noise transmission, along with putting it on rubber bolt cushions. Cheaper than a new quieter generator at this point.

BTW, if you are in Central TX, I recommend Fred Summers and Gen-Tec (aka FixYourGenerator.com). He came highly recommended to me, and I'd agree that he and his team does quality work.

 

[inforiculturist]

However, I don't see how adding the resonator aft of the spark-arrestor would violate the national forest rules.

My sole point was about decibels, but was poorly communicated.

It's not about how the resonator is mounted. It's about the level of decibels, that according to one post I read (not finding it now) suggested there was less than 1dB overall reduction while changing the frequency of the sound. The MicroLite 2800 still doesn't get quiet enough but apparently the GQ versions do).

And I meant to say National Park rules instead of US Forest Service. I'm not finding rules from USFS.

National Park Rules:
Generators must conform to National Park Service regulations pertaining to audio disturbances, which states that "motorized equipment or machinery cannot exceed a noise level of 60 decibels measured on the A-weighted scale at 50 feet" (36 CFR 2.12).

 

[NFRicaS]

Help in ATX??

They make a resonator that while the dB level doesn't go down, the harsher high pitched notes do making it seem less noisy. Unfortunately, they don't get quieter and don't meet current rules for national forests.

Hi, I’m in ATX, and looking for help with my generator exhaust system, (or lack thereof..) Basically, there is no pipe of any kind, so need to order or get a pipe made since it is dangerous as it is, with no exhaust..

I saw your posts on this subject...trying to figure out what he best route is to get the safest, quietest solution...Anyone who you know who can do this type of work in Austin would be appreciated, too...TIA

 

[rowiebowie]

Hi, I’m in ATX, and looking for help with my generator exhaust system, (or lack thereof..) Basically, there is no pipe of any kind, so need to order or get a pipe made since it is dangerous as it is, with no exhaust..

I saw your posts on this subject...trying to figure out what he best route is to get the safest, quietest solution...Anyone who you know who can do this type of work in Austin would be appreciated, too...TIA

I recommend you buy an Onan replacement off EBay or Amazon. You'll need the replacement for your model Generator. Most are just one or two shapes I believe. You'll need a clamp (at the generator) and a strap hanger (at the van fender where the end sticks out). Plus, go ahead and clean the spark-arester screen while your exhaust pipe is off.

Here's what the Onan exhaust pipe looks like on my Airstream Avenue (Chevy Express chassis) and removed.

LATER, you can add a resonator if you desire, but get the exhaust pipe back on first.

 

[Joe-ClassB]

Joe

Not sure where your gen. is located. The pipe in picture would never connect to mine. My gen. is located inside a rear hatch. I fabricated a pipe out of electrical conduit.

 

[NFRicaS]

I recommend you buy an Onan replacement off EBay or Amazon. You'll need the replacement for your model Generator. Most are just one or two shapes I believe. You'll need a clamp (at the generator) and a strap hanger (at the van fender where the end sticks out). Plus, go ahead and clean the spark-arester screen while your exhaust pipe is off.

Here's what the Onan exhaust pipe looks like on my Airstream Avenue (Chevy Express chassis) and removed.

LATER, you can add a resonator if you desire, but get the exhaust pipe back on first.

Where is spark arrestor screen? I only have that open hole...My Chevy 3500 and generator look just like your, but I can’t tell on Amazon anything that has model #’s etc....but the one I looked at looks like it would fit...I’ll give it a shot...Thanks for the pics, very helpful!!

 

[rowiebowie]

Where is spark arrestor screen? I only have that open hole...My Chevy 3500 and generator look just like your, but I can’t tell on Amazon anything that has model #’s etc....but the one I looked at looks like it would fit...I’ll give it a shot...Thanks for the pics, very helpful!!

I labled your pic. The spark arrestor fits inside the muffler and is held in place by a bolt on one side. The bold it hard to get to and I feared I would not be able to line it up with the hole to bolt my spark arrestor back on if I removed it. So I left it in place and instead checked it with a flashlight. It is pretty high up inside and not easy to see. The screen was intact and and not clogged; just a bit sooty. I sprayed with several doses of carburetor cleaner up there to wash it out. Nothing too bad came out so I re-installed my exhaust pipe and called it a day.

 

[NFRicaS]

I labled your pic. The spark arrestor fits inside the muffler and is held in place by a bolt on one side. The bold it hard to get to and I feared I would not be able to line it up with the hole to bolt my spark arrestor back on if I removed it. So I left it in place and instead checked it with a flashlight. It is pretty high up inside and not easy to see. The screen was intact and and not clogged; just a bit sooty. I sprayed with several doses of carburetor cleaner up there to wash it out. Nothing too bad came out so I re-installed my exhaust pipe and called it a day.

Thanks again!!! I appreciate the help!!

 

[mkguitar]

I have a 2006 Lexor TD on chev 3500


my genny exhaust looks similar to the pic above, running alongside the vehicle exhaust







mike

 

[booster]

Yes be sure to make sure you have a spark arrestor, you don't want to start a big fire anywhere.


Most of the Onans in class b's use 1.25" diameter exhaust tubing, which can be a bit hard to find, but is readily available. It is harder to find anyone who has the bending dies to make custom pipes in 1.25" diameter because most of the size is used in cut and well for headers and motorcycles exhausts.


The Onans are easy to duplicate, I have done them myself at home without issue. Just look and see about what you need for bends and straight tubing and buy the prebent pieces which will normally be very nice mandrel bent pieces for headers in 1.25". Take them to a custom exhaust shop and they should be able to cut and weld to make a very nice pipe and put in a resonator if you get one.



Here is a link to the tubing, and they should also have the 1.25" clamps and hangers.



https://www.summitracing.com/search/part-type/exhaust-tubing?N=pipe-diameter:1-250-in


The other option is to have a custom shop make a pipe in more common 1.375" diameter and put an adapter the the Onan muffler. Also very straightforward, IMO.

 

[rowiebowie]

I you have to have an exhaust fabricated, then might as well do the Onan resonator install. Not a big improvement, but lowers the exhaust tone enough that it's worth it.

It can be installed near the generator, or at the end if you use a larger u-bolt on the hanger strap.

PS- Did you ever determine what happened to your exhaust pipe? If not, it most likely resulted from the rubber on the original hanger strap cracking in two. Once this end support is lost, the clamp at the muffler cannot support the weight and it probably dropped on the road somewhere. I replaced my hanger strap just before the rubber broke on mine. I used the opportunity to install the resonator which I had done at a local muffler shop.

 

[NFRicaS]

I you have to have an exhaust fabricated, then might as well do the Onan resonator install. Not a big improvement, but lowers the exhaust tone enough that it's worth it.

It can be installed near the generator, or at the end if you use a larger u-bolt on the hanger strap.

PS- Did you ever determine what happened to your exhaust pipe? If not, it most likely resulted from the rubber on the original hanger strap cracking in two. Once this end support is lost, the clamp at the muffler cannot support the weight and it probably dropped on the road somewhere. I replaced my hanger strap just before the rubber broke on mine. I used the opportunity to install the resonator which I had done at a local muffler shop.

Nope, guess it was gone when I got RV? Not sure...are these last pics from a previous RV?
Will look into the resonator thing...I have rarely used the generator, except to exercise it...headed to Maine this week, and can’t get to a CG in VA, so thought I’d have to find somewhere else and use generator, but since it has no exhaust, too dangerous!! Well, lesson learned...should have gotten going on this months ago!! Thanks again for your help and the pics...!!

 

[rowiebowie]

Nope, guess it was gone when I got RV? Not sure...are these last pics from a previous RV?
Will look into the resonator thing...I have rarely used the generator, except to exercise it...headed to Maine this week, and can’t get to a CG in VA, so thought I’d have to find somewhere else and use generator, but since it has no exhaust, too dangerous!! Well, lesson learned...should have gotten going on this months ago!! Thanks again for your help and the pics...!!

One resonator pic is from my Airstream Avenue, but the other is from an Airstream Avenue owner who posted pics on airforums.com. Just to show there's more than one location to add it.

 

[mkguitar]

! Thanks again for your help and the pics...!!

I can't post pics from my 2006 Lexor TD... I could maybe email?

 

[NFRicaS]

I can't post pics from my 2006 Lexor TD... I could maybe email?

Thanks, I think I am all set, but will let you know if not!! I think if you hit quote, and do advanced it will let you attach a photo...that’s what I did...

 

[mkguitar]

Thanks, I think I am all set, but will let you know if not!! I think if you hit quote, and do advanced it will let you attach a photo...that’s what I did...

Let's see...

 

[Deano-ClassB]

Something to keep in mind. My RT has the generator exhaust pipe exiting out the drivers side. I believe it is because the awning is on the passenger side and that side is where we normally are.

 

[mkguitar]

Something to keep in mind. My RT has the generator exhaust pipe exiting out the drivers side. I believe it is because the awning is on the passenger side and that side is where we normally are.

that is a good! consideration-



thinking about it;


I think the pleasureway has the skirting cutout on the pass side


and the drivers side has the fuel line for the genny.


def something to look at if I ever need a genny exhaust.




update, just had a look, really only path for me on the pleasureway lexor would be rear of wheel well.
learned on an old pickup truck that a poorly placed exhaust can be destroyed by a blown tire as the rubber whips around



Mike

 

[NFRicaS]

Something to keep in mind. My RT has the generator exhaust pipe exiting out the drivers side. I believe it is because the awning is on the passenger side and that side is where we normally are.

Thanks for suggesting that!!