Quieting a gasoline driven compressor?

[mhorowit]

In the last 6 month's I've rescued a gasoline-driven air compressor. It gives me 125PSI and a volume that seems to fit my needs (translation - so far, so good); unfortunately it's LOUD. I replaced the muffler on the 5.5 hp Honda engine but it's still LOUD.
Short of putting it in an insulated box, or converting it to electric, anyone have any ideas how I might quiet it? - Mike

[jgerard]

Re: Quieting a gasoline driven compressor?

a lot of the noise from an air-compressor is from the intake on the air pump. Take the belt off the pump wheel and see just how loud the gas engine is by its self.

[VictorBravo]

Re: Quieting a gasoline driven compressor?

I htink enclosing it is better overall, if it is possible.

Enclose it with cheap cinder blocks or bricks stacked up. Don't even need to mortar or cement anything. Or you could use some sandbags or even fertilizer bags.

Just find the biggest cheapest most dense thing you can find at the local home improvement or building supply (except me if you happen to see me there).

Plastic jugs filled with dirt... water...asphalt mix in plastic lined crates, stacks of newspapers and phone books.

If you cannot enclose it for some reason then go get a cheap car muffler and some conduit tube and weld up an adapter that allows the larger muffler to be used in place of the stock muffler.

Running the exhaust pipe into a tub of water might be worth a try too.

[Guest]

Re: Quieting a gasoline driven compressor?

In the last 6 month's I've rescued a gasoline-driven air compressor. It gives me 125PSI and a volume that seems to fit my needs (translation - so far, so good); unfortunately it's LOUD. I replaced the muffler on the 5.5 hp Honda engine but it's still LOUD.
Short of putting it in an insulated box, or converting it to electric, anyone have any ideas how I might quiet it? - Mike

One time I bought a piece of flex exhaust brazed a piece of mail pipe thread on one end and and exhaust flange on the other.

Attached to my generator and bolted to a porche muffler on the other.

Also tried one of the those generic $15 Sears mufflers too.

That was a while ago and I recall that the noise was still loud.

Dave

[Hank Jarrett]

Re: Quieting a gasoline driven compressor?

There are a hundred different things that cause noise on a compressor system. I solved MY problem by putting the compressor on the other side of a wall and running the hose through. Still loud, but not for me.
To kill the maximum noise you need to attack it in a couple of ways. Running the exhaust through a large expansion chamber will cut a lot of the exhaust pulse out the pipe. There is still a lot of the pulse that comes through the muffler case and it can be absorbed by putting the muffler in a second container (even a coffee can around the real muffler with steel wool between it and the can). The second big one is the intake and the same process works. Pull the intake air through a muffler just like the motor exhaust. The last noise source is mechanical. Get rid of all the vibration you can and the rest will be controllable with a plywood box over the compressor. The danger is you trap all the engine heat inside with the noise and burn the whole rig up. Of course that makes the compressor REAL quiet. Seriously, vibration is your enemy on the mechanical noise. Even sitting the whole unit on a piece of carpet will help a lot. DON’T box it in unless you have good cooling.
Hank

[ClipWing_T]

Re: Quieting a gasoline driven compressor?

The easiest and most effective way is to use ear plugs like the
foamy types or a headset type like at the gun range. I have
tinnitus (constant ringing in the ears 24-7) and believe me I
wished i had taken better precautions for my hearing . The
foamy ear plugs are cheap and comfortable and work ! :-)
Mike

[tawadc95]

Re: Quieting a gasoline driven compressor?

fertilizers can be flammable.

[mhorowit]

Re: Quieting a gasoline driven compressor?

The easiest and most effective way is to use ear plugs like the
foamy types or a headset type like at the gun range. I have
tinnitus (constant ringing in the ears 24-7) and believe me I
wished i had taken better precautions for my hearing . The
foamy ear plugs are cheap and comfortable and work ! :-)
Mike

I'm thinking more about the neighbors; I won't fire it up until 1100 on saturday and not until noon on sunday. Got good ear protectors for myself MikeH

[flyguy]

Re: Quieting a gasoline driven compressor?

Mike,
What I have found that works best on this type of problem is "divide and conquer." Use any cheapo/easy method you can, even if it cannot be used for more than a few seconds, to see what item on the complete unit is making the most noise. Then you can find a rugged permanent method to correct that problem. Then work down your noise list in order of loudness.
E.G. you can wrap an offending part in a material that might catch fire if left on for more than a few minutes, but you only test it a minute or 2.
Darryl

[Len Petterson]

Re: Quieting a gasoline driven compressor?

If you are inside a building the sand bags sounds like good idea.
With lid of heavy plywood in 2 layers with insulation in between.
Remember what the engine need cooling and combustion air to be happy!
air intake from the outside if possible.
TSC has all kinds of tractor mufflers what may work.
Keep an eye on the running temperature in the begining untill you are shure the engine is not to hot, remember the possibilety of vaporlock if it gets to hot.
Len

[N96337]

Re: Quieting a gasoline driven compressor?

Put it in the neighbor's garage.....
JH

[tawadc95]

Re: Quieting a gasoline driven compressor?

I like that...lol

[flyguy]

Re: Quieting a gasoline driven compressor?

How about this for a cheap muffler. Use a post hole digger to dig about 3 ft deep. Run the exhaust pipe down into the hole until is is about 6 inches from the bottom.
Bet it kills all your trees. LOL, and your grass.
DC
Oh yeah, added benefit, gets rid of gophers and moles.

[fearofpavement]

Re: Quieting a gasoline driven compressor?

Earlier in this post someone mentioned that compressor noise can be from the compressor intake. I agree with this. Compressors tend to be noisy even if they are electrically powered. Take the belt off a noisy air compressor that is driven by an electric motor and the motor will make a soft hum. So while engine noise can certainly be a factor, much of what you're hearing is probably not the engine. Some of the Honda generators that have a gas engine are very quiet. So if your muffler is in good shape probably making a barrier for the noise as suggested would be best. Don't run any gasoline powered engine in an enclosed space. I would think those on this forum would know that but dead people are found every winter that died of carbon monoxide gas poisoning. Glad you got some compressed air finally. (Is this the two cylinder compressor you were going to run as a one cylinder?)

[tawadc95]

Re: Quieting a gasoline driven compressor?

Flyguy,
if mikes grass and trees are like all the oleanders on hwy 99 they will thrive from all that co