Lister Engine Forum

Lister Engines => Listeroid Engines => Topic started by: veggie on October 17, 2019, 05:46:18 PM

Title: QUIET Exhaust - Listeroid - HOW?
Post by: veggie on October 17, 2019, 05:46:18 PM

I'm looking for ideas to make a listeroid exhaust super quiet for residential use without having to dig a hole in the ground and bury everything.
Other houses are within 150 ft of the engine location.
I want to run the unit for 4 hrs per day without upsetting the neighbors.
Has anyone built a silent exhaust system for their Lister/roid?
Title: Re: QUIET Exhaust - Listeroid - HOW?
Post by: dax021 on October 17, 2019, 06:06:46 PM
But a Lister exhaust throb is a beatiful sound and so nice for rocking one to sleep.  Your neighbours should pay you to listen to that exhaust.
Title: Re: QUIET Exhaust - Listeroid - HOW?
Post by: mike90045 on October 17, 2019, 07:10:22 PM
But a Lister exhaust throb is a beautiful sound and so nice for rocking one to sleep.  Your neighbours should pay you to listen to that exhaust. 


I cannot improve on that statement.

But what I did, was have an adapter welded up to 2" pipe, a flanged diesel truck braided flex hose, and then into a good sized truck muffler.  It's not silent, but a steady thump thump, about as loud at the mechanical rattle from the camshaft stuff.
See the link in my .sig for lister running , for a short video
Title: Re: QUIET Exhaust - Listeroid - HOW?
Post by: veggie on October 17, 2019, 08:45:01 PM
The concern is that if the lister is running at 10PM there may be issues with neighbours.
Especially if it runs for 4 hours before automatically shutting off when the water storage tank reaches 180f.
Sound travels at night.
I have seen some very quite systems where there is hardly any exhaust pop at all, but they have been underground tanks.
Title: Re: QUIET Exhaust - Listeroid - HOW?
Post by: veggie on October 18, 2019, 02:17:13 AM
... I'm thinking of 3 large automotive mufflers in a row. Something like 2-1/2" inlet/outlet sizes.
Anyone tried that? I wonder about the back pressure.
Title: Re: QUIET Exhaust - Listeroid - HOW?
Post by: saba on October 18, 2019, 02:44:01 AM
I had the same problem, tried a lot of things but always the deep bass sound remained. I made a labyrinth box with rockwool inside. Three chambers ,30cm/45cm/160cm wide high lenght . There is just fumes coming and no sound at all. I should have a video somewhere I'll try to find it.

Bernhard
Title: Re: QUIET Exhaust - Listeroid - HOW?
Post by: LowGear on October 18, 2019, 10:28:03 AM
How about a sound cancelling loudspeaker system?

A split exhaust with one arm traveling far enough to provide a half hertz phase shift before reuniting them?
Title: Re: QUIET Exhaust - Listeroid - HOW?
Post by: glort on October 18, 2019, 02:02:33 PM

Have you measured/ addressed the intake noise? That is at least as loud as the exhaust if not more.
Mechanical clatter on these things isn't too loud but some sound isolation wouldn't hurt.  Intake noise can be reduced with a muffler as well.  Alternately, Vehicles often have large intake boxes to aid with sound suppression and resonance.  They have large air filters that would last a very long time on a roid.

Exhaust noise is largely about gas flow and slowing it down. I don't think there is any need to go overboard, a decent diameter muffler  from a car will have more than the capacity to reduce the flow so exhaust noise is virtually eliminated.  Due to the characteristics of the Lister engine I would suggest an internal restrictor after the muffler of a capacity at least 2X that of the engine so the gas pressure is bled down rather than pulsed to atmosphere. Some insulation of the muffler itself may also suppress sound coming from the walls of the muffler. Double skinned mufflers will help address this.

Also pay attention to direction and reflection of the sound.
Title: Re: QUIET Exhaust - Listeroid - HOW?
Post by: veggie on October 18, 2019, 03:25:32 PM
I had the same problem, tried a lot of things but always the deep bass sound remained. I made a labyrinth box with rockwool inside. Three chambers ,30cm/45cm/160cm wide high length . There is just fumes coming and no sound at all. I should have a video somewhere I'll try to find it.

Bernhard

From what material did you build the labyrinth box?
Title: Re: QUIET Exhaust - Listeroid - HOW?
Post by: saba on October 18, 2019, 11:00:43 PM
Behind the lister I had a big exhaustgas cooler so the gas exits at cooling water temp, max 90 degr C .

I made the box out of wood / thin plywood lined it with rockwool, inside I have to walls so you have three chambers. a pipe threw these walls in a way that the sound bounces of the opposing wall and cannot enter the next pipe directly.
If you look at a cut open car exhaust same thing only bigger with rockwool. Rockwool was rockfon ceiling plates like the ones they use in offices, but I am sure any kind will work
It was overkill because there was no noise at all even with your ear next to the exhaust.
Had to do it because I live really close to the neighbours.

The flaw of the design, exhaust gasses condensing in the last chamber with hot coolingwater and cold outside temps.

I think the yanmar will be easier to shut up, I am thinking of making a similar design but maybe in an old air compressor tank with a water drain at the bottem...

But rockwool labyrinth you can kill any sound or anyone without disturbing the neighbours.

Bernhard
Title: Re: QUIET Exhaust - Listeroid - HOW?
Post by: veggie on October 24, 2019, 04:27:44 PM

Underground mufflers can be extremely quiet ...
https://www.youtube.com/watch?v=B2682AwYJ7w (https://www.youtube.com/watch?v=B2682AwYJ7w)
Title: Re: QUIET Exhaust - Listeroid - HOW?
Post by: saba on October 24, 2019, 08:26:31 PM
I had seen that one as well on my search for silence, but no place to dig a whole. There are also drawings in the start o matic manual with sizes of the pit If you can it is the best way to go i think.

Bernhard
Title: Re: QUIET Exhaust - Listeroid - HOW?
Post by: gadget on October 25, 2019, 04:18:46 AM
Behind the lister I had a big exhaustgas cooler so the gas exits at cooling water temp, max 90 degr C .

I made the box out of wood / thin plywood lined it with rockwool, inside I have to walls so you have three chambers. a pipe threw these walls in a way that the sound bounces of the opposing wall and cannot enter the next pipe directly.
If you look at a cut open car exhaust same thing only bigger with rockwool. Rockwool was rockfon ceiling plates like the ones they use in offices, but I am sure any kind will work
It was overkill because there was no noise at all even with your ear next to the exhaust.
Had to do it because I live really close to the neighbours.

The flaw of the design, exhaust gasses condensing in the last chamber with hot coolingwater and cold outside temps.

I think the yanmar will be easier to shut up, I am thinking of making a similar design but maybe in an old air compressor tank with a water drain at the bottem...

But rockwool labyrinth you can kill any sound or anyone without disturbing the neighbours.

Bernhard

Saba, could you do a really basic sketch with basic dimensions? I'm having trouble visualizing. I think you are on to something here. I need to have a quiet exhaust too due to close neighbors.
Title: Re: QUIET Exhaust - Listeroid - HOW?
Post by: saba on October 26, 2019, 02:03:57 AM
Took a picture with my phone from paper now it all looks bent. Other picture is showing part of the box and my exhaust cooler. It's all black because of the cleaning of the clogged up cooler each time. A job to look forward to.
Pipe going in the box is pvc sewer pipe 110mm I guess. Exhaust gas is below 90degr celcius so After the cooler its all plastic.
You can see my olive green ceiling tiles every where these also in the box.

So I made 4 chambers, really overkill it's absurd silent.

I have a small alley in between my house and the nabours where the exhaust exits, with a previous version I had it all silent but the thump of the exhaust you felt in your stomach the moment you entered the alley.

For the design improvements, inside it looks like a black hole combined with chernobyl. I experimented with fuels and had a stuck injector once.....
Lister cs does not run on HFO380 even when it's hot and mixed with a lot of diesel.....

I need to take it out but the mess it will give is keeping me from it.

Hope it helps for your project

regards Bernhard
Title: Re: QUIET Exhaust - Listeroid - HOW?
Post by: saba on October 26, 2019, 02:21:16 AM
Ok I saw I mixed mm's and cm, 168cm long.

For improvement make it water proof with a drain (condensating exhaust). The tubing inside was stainless air duct tubing. Tiles are compressed rockwool ceiling plates . I have the hole engine space patched up they suck up most of the noise.
Of course I sealed everything with silicone.

The size was determined by the space available as big as I could go.

Bernhard
Title: Re: QUIET Exhaust - Listeroid - HOW?
Post by: carlb23 on October 27, 2019, 12:11:50 PM
I took an old 20lb propane tank and cut a hole in the top and bottom.  I welded threaded pipe couplings to both ends and i run the exhaust into one end and out the other.  it acts like an accumulator and allows the release of exhaust gases more slowly.  behind that i have a 2.5"diameter  car muffler and the exhaust pipe goes outside from there.  Outside i transition to a 15" length of 4" pvc that is on the ground with a reducer at the other end back to 2".  You can't hear the exhaust 25 feet away at all.
Title: Re: QUIET Exhaust - Listeroid - HOW?
Post by: George A on October 27, 2019, 10:44:51 PM
Since my wife.........and the neighbors.........object to the sound of my 6/1, I've been thinking about using a propane tank also, but with a slightly different setup.

Note: The wife's objections are toned down a bit when we still have lights/t.v. and everyone else doesn't. :)

My idea is to run the exhaust into the side of the tank, at the top. Then, a second pipe will be located at the top and extend all the way down to the bottom, but about one inch from it. The idea is to have the exhaust enter and begin swirling a bit, as it travels to the bottom where it can begin exiting back up through the other pipe. A rain stack and condensate drain would complete the assembly.

I have no proof that such a setup would be better or fool proof, but it WOULD circulate, cool and let the gasses expand before exiting. Somewhat like the old cyclonic air filters worked. At any rate, it HAS to be better than that "pepper pot" muffler that came with the engine!
Title: Re: QUIET Exhaust - Listeroid - HOW?
Post by: gadget on October 29, 2019, 04:54:39 AM
Saba, thanks for the pic and drawing. I was thinking it could be done with one chamber but I see you had 4 in the drawing.

If temps are low enough, I wonder if egg krate foam shape could be used to line the inside of the box. The foam is great at absorbing sound waves and the spikes shapes are good at breaking up the sound waves.

There is also the air pulse to deal on top of the sound waves. I'm guessing from everyones comments, the key elements are a large chamber(s) and some sound absorbing material liner.
Title: Re: QUIET Exhaust - Listeroid - HOW?
Post by: George A on October 30, 2019, 05:53:54 AM
Why not try some R-max instead? R-max is a stiff, foil covered foam available at most lumber yards and is used as insulation. It comes in 4' x 8' sheets, 1" and 2" thicknesses. Easily cut and either glued or fastened with clamps inside your muffler.
Title: Re: QUIET Exhaust - Listeroid - HOW?
Post by: gadget on October 31, 2019, 12:50:18 AM
Why not try some R-max instead? R-max is a stiff, foil covered foam available at most lumber yards and is used as insulation. It comes in 4' x 8' sheets, 1" and 2" thicknesses. Easily cut and either glued or fastened with clamps inside your muffler.

The foam should help dampen sound waves since we are only dealing with a low frequency noise. I like the idea of rock wool
Title: Re: QUIET Exhaust - Listeroid - HOW?
Post by: Jordan on February 18, 2020, 07:37:29 AM
There's drawing from a Lister SOM booklet that shows an exhaust system that could be excellent.
Also, it looks like it would be cheap and easy to accomplish.

Jordan
Title: Re: QUIET Exhaust - Listeroid - HOW?
Post by: saba on February 18, 2020, 11:19:01 AM
Hello Jordan, if you have a garden or place to dig a hole for sure that's the way to go.
Title: Re: QUIET Exhaust - Listeroid - HOW?
Post by: veggie on February 18, 2020, 07:35:57 PM
Yes, the official Lister design using an underground concrete chamber is very effective.
https://www.youtube.com/watch?v=B2682AwYJ7w (https://www.youtube.com/watch?v=B2682AwYJ7w)
Title: Re: QUIET Exhaust - Listeroid - HOW?
Post by: glort on February 19, 2020, 11:10:07 AM

As long as the exhaust is as quiet as the mechanical clatter, that's all you need in most cases.

I really think the pit system is complete over kill. Get a decent large car muffler and you wont hear anything either especially if the engine isn't as enclosed and soundproofed as the one in the vid. I put a Muffler off a Subaru on my roid and you couldn't hear it and it's not even a big Muffler.

Other thing if the engine isn't enclosed is the intake noise. That was a lot more on my engine than the exhaust even when I just had 1.5M  of large Diameter pipe stuffed with a few pot scrubbers and necked down.  Again, used an airbox and filter from a car with the factory moulded and tuned intake ( for a 4 Cyl) and it hushed the intake up a LOT.

Intake and Exhaust are pretty easy to get so you can't hear them over the mechanical clatter these engines make.
Title: Re: QUIET Exhaust - Listeroid - HOW?
Post by: Hugh Conway on February 21, 2020, 12:19:21 AM
I tried a few different mufflers, guess I didn't get the right one.
Dug a hole. the "pit of doom" works great for quieting things down.
Here's a link to an old thread about the "Pit" that contains 38AC, Bruce and others......
https://listerengine.com/smf/index.php?topic=7773.0
An air compressor intake filter works great, screws right in. Makes a huge difference with not very much expense.
Now, that noisy valve-gear!
Cheers
Hugh
Title: Re: QUIET Exhaust - Listeroid - HOW?
Post by: Hugh Conway on February 21, 2020, 12:35:42 AM
Re the intake side of things:
An ancient thread that already has that solution, It works very well. There are other ways too, but this is as simple as it gets....just get a Solberg and screw it in.
Here's one:  https://www.solbergmfg.com/filters-traps-silencers/inlet-filtration-silencing/fs-ps-series/fs-19-150

Or different Mfg:  https://www.ecompressedair.com/eca-pfs-19p-150-air-intake-assembly-w-silencer.aspx
I 'm using that one.

Cheers
Hugh