Silencer for trimmers ?
- Thread starter gardentec
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I can tell you by experience. And I have a way to REALLY silence one down.
Believe it or not, most of the noise you hear comes from the INTAKE! The noise is coming from the airbox! On a two cycle, when the intake port opens, the exhaust port is open at the same time. you get the same noise going both ways. the exhaust has a muffler. Its pretty quiet. You need to spend your efforts on quieting the air intake down. If you're serious I can help you do it. I played around with a common lawnmower muffler. The one that looks like a hot dog. If you force the carburetor to suck air through it the opposite way it is designed to flow exhaust, it will COMPLETELY quieten down the trimmer engine. I mean 10 times quieter! You will have to fabricate a way to connect the lawn mower muffler to the carb. I have simple solutions for that if you'd like to talk about it. On the other end you simply attach a Uni type pod air filter. As long as this setup doesn't hit your body while you're using it, it will work great! This setup makes one of these engines sound like a distant vacuum cleaner. I can provide links to the parts you need to make this setup. Let me know and I'll do the footwork for you.
...but you weren't talking about quieting the string down were you.... ???
Believe it or not, most of the noise you hear comes from the INTAKE! The noise is coming from the airbox! On a two cycle, when the intake port opens, the exhaust port is open at the same time. you get the same noise going both ways. the exhaust has a muffler. Its pretty quiet. You need to spend your efforts on quieting the air intake down. If you're serious I can help you do it. I played around with a common lawnmower muffler. The one that looks like a hot dog. If you force the carburetor to suck air through it the opposite way it is designed to flow exhaust, it will COMPLETELY quieten down the trimmer engine. I mean 10 times quieter! You will have to fabricate a way to connect the lawn mower muffler to the carb. I have simple solutions for that if you'd like to talk about it. On the other end you simply attach a Uni type pod air filter. As long as this setup doesn't hit your body while you're using it, it will work great! This setup makes one of these engines sound like a distant vacuum cleaner. I can provide links to the parts you need to make this setup. Let me know and I'll do the footwork for you.
...but you weren't talking about quieting the string down were you.... ???
This has to be a script from Home Improvement featuring Tim "tool time" Taylor
And the guy from the other side of the fence you never see.
OK. Let it roll.
And the guy from the other side of the fence you never see.
OK. Let it roll.
Trimmers are "loud"? Huh............
To clarify my post, here's what you do to silence the intake noise;
Remove the stock airbox. If you can weld, fabricate a steel flange and pipe the same diameter of the lawn mower muffler. Or you can buy an aftermarket velocity stack made for scooters or large scale r/c models that use Walbro or Zama type carburetors. There are stacks for other oddball carbs too. They all are designed to take a Uni type air filter, but instead of putting on an air filter, using a short length of radiator hose, connect the velocity stack to the EXIT side of the muffler. That's right. Put it on backwards. For some reason, and this is the secret, it quietens down much better when the air is being sucked through the side that the smoke would come out on a lawn mower.
Now, on the other end of the muffler you will have the threaded end of the muffler sticking out. You can cut it off to make the assembly more compact or leave it and simply slip a Uni-type air filter over the OD of the muffler, covering up the threaded end.
Try it with the threaded portion on first. That's how I did mine and it made a Dramatic difference in the noise coming from the engine, so I never cut the threads off. I mean it made a DRAMATIC difference. Its hard to believe all that noise is coming from the airbox, until you think about how a 2 cycle engine works. Large 2 stroke engines like on a dirt bike have reed valves in the intake tract that shut and stop the sound pulse that comes back out of the air filter on the little lawn equipment engines.
Now, if your choke is integral with the original airbox, they make chokes that sandwich between the aftermarket velocity stacks and the carb. Its a sliver of aluminum with a thin steel blade that slides. They are for the scooter and r/c engines too.
Here's a link that has the velocity stacks, chokes, and filters all on one page!
http://www.davesmotors.com/Products/AF-Air-Filters
Here's one for the muffler.
http://www.tractorsupply.com/en/store/arnold-replacement-muffler-for-briggs--stratton-89966
You'll have to find the piece of radiator hose and hose clamps yourself!
Trust me. The noise emanating from your airbox is 10 times louder than that emanating from the muffler on your weed trimmer. I'm serious. This trick made my engine 10 times quieter!
Remove the stock airbox. If you can weld, fabricate a steel flange and pipe the same diameter of the lawn mower muffler. Or you can buy an aftermarket velocity stack made for scooters or large scale r/c models that use Walbro or Zama type carburetors. There are stacks for other oddball carbs too. They all are designed to take a Uni type air filter, but instead of putting on an air filter, using a short length of radiator hose, connect the velocity stack to the EXIT side of the muffler. That's right. Put it on backwards. For some reason, and this is the secret, it quietens down much better when the air is being sucked through the side that the smoke would come out on a lawn mower.
Now, on the other end of the muffler you will have the threaded end of the muffler sticking out. You can cut it off to make the assembly more compact or leave it and simply slip a Uni-type air filter over the OD of the muffler, covering up the threaded end.
Try it with the threaded portion on first. That's how I did mine and it made a Dramatic difference in the noise coming from the engine, so I never cut the threads off. I mean it made a DRAMATIC difference. Its hard to believe all that noise is coming from the airbox, until you think about how a 2 cycle engine works. Large 2 stroke engines like on a dirt bike have reed valves in the intake tract that shut and stop the sound pulse that comes back out of the air filter on the little lawn equipment engines.
Now, if your choke is integral with the original airbox, they make chokes that sandwich between the aftermarket velocity stacks and the carb. Its a sliver of aluminum with a thin steel blade that slides. They are for the scooter and r/c engines too.
Here's a link that has the velocity stacks, chokes, and filters all on one page!
http://www.davesmotors.com/Products/AF-Air-Filters
Here's one for the muffler.
http://www.tractorsupply.com/en/store/arnold-replacement-muffler-for-briggs--stratton-89966
You'll have to find the piece of radiator hose and hose clamps yourself!
Trust me. The noise emanating from your airbox is 10 times louder than that emanating from the muffler on your weed trimmer. I'm serious. This trick made my engine 10 times quieter!
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I purchased a Toro commercial head unit for my Ryobi attachments. It's got a catalytic converter in the muffler, and the exhaust is very quiet.
However, as mentioned above, there is a roar from the intake that is nearly intolerable.
I don't use this particular powerhead for much, so I don't worry too much about the noise, but now you've got me thinking about fabricating a tube to "remote mount" an air cleaner/silencer. Could be rather easy and effective.
However, as mentioned above, there is a roar from the intake that is nearly intolerable.
I don't use this particular powerhead for much, so I don't worry too much about the noise, but now you've got me thinking about fabricating a tube to "remote mount" an air cleaner/silencer. Could be rather easy and effective.
Ear plugs are a pretty effective silencer.
They make the trimmer nice and quiet, and as an added bonus you can't hear the wife yelling at you when you accidentally trim her flowers.
They make the trimmer nice and quiet, and as an added bonus you can't hear the wife yelling at you when you accidentally trim her flowers.
Originally Posted By: j_mac
connect the velocity stack to the EXIT side of the muffler. That's right. Put it on backwards. For some reason, and this is the secret, it quietens down much better when the air is being sucked through the side that the smoke would come out on a lawn mower.
That's no secret. You actually aren't installing it "backwards" as that's the normal direction of air flow through a muffler.
connect the velocity stack to the EXIT side of the muffler. That's right. Put it on backwards. For some reason, and this is the secret, it quietens down much better when the air is being sucked through the side that the smoke would come out on a lawn mower.
That's no secret. You actually aren't installing it "backwards" as that's the normal direction of air flow through a muffler.
Originally Posted By: j_mac
I can tell you by experience. And I have a way to REALLY silence one down.
Believe it or not, most of the noise you hear comes from the INTAKE! The noise is coming from the airbox! On a two cycle, when the intake port opens, the exhaust port is open at the same time. you get the same noise going both ways. the exhaust has a muffler. Its pretty quiet. You need to spend your efforts on quieting the air intake down. If you're serious I can help you do it. I played around with a common lawnmower muffler. The one that looks like a hot dog. If you force the carburetor to suck air through it the opposite way it is designed to flow exhaust, it will COMPLETELY quieten down the trimmer engine. I mean 10 times quieter! You will have to fabricate a way to connect the lawn mower muffler to the carb. I have simple solutions for that if you'd like to talk about it. On the other end you simply attach a Uni type pod air filter. As long as this setup doesn't hit your body while you're using it, it will work great! This setup makes one of these engines sound like a distant vacuum cleaner. I can provide links to the parts you need to make this setup. Let me know and I'll do the footwork for you.
...but you weren't talking about quieting the string down were you.... ???
I want to thank you for this post. It was very clever of you to figure this out. The noise on my trimmer does not bother me but this is such a neat mod i almost want to try it just for fun.
I can tell you by experience. And I have a way to REALLY silence one down.
Believe it or not, most of the noise you hear comes from the INTAKE! The noise is coming from the airbox! On a two cycle, when the intake port opens, the exhaust port is open at the same time. you get the same noise going both ways. the exhaust has a muffler. Its pretty quiet. You need to spend your efforts on quieting the air intake down. If you're serious I can help you do it. I played around with a common lawnmower muffler. The one that looks like a hot dog. If you force the carburetor to suck air through it the opposite way it is designed to flow exhaust, it will COMPLETELY quieten down the trimmer engine. I mean 10 times quieter! You will have to fabricate a way to connect the lawn mower muffler to the carb. I have simple solutions for that if you'd like to talk about it. On the other end you simply attach a Uni type pod air filter. As long as this setup doesn't hit your body while you're using it, it will work great! This setup makes one of these engines sound like a distant vacuum cleaner. I can provide links to the parts you need to make this setup. Let me know and I'll do the footwork for you.
...but you weren't talking about quieting the string down were you.... ???
I want to thank you for this post. It was very clever of you to figure this out. The noise on my trimmer does not bother me but this is such a neat mod i almost want to try it just for fun.
thanks for the responses
, and j-mac thanks i knew someone had to invent something like this
, the problem is j-mac you say lawn mower : / and what i have is a trimmer can this mo be one on it ?
this is my trimer : )
this is not my video
but you can see it an see if what you describe in your mo can b done : )
http://www.youtube.com/watch?v=vUStszWi7JY
this is the manual with some parts schematic , maybe that also helps you to see if the mod can be done : )
http://www.hitachi-powertools.com.au/Media/Documents/CG22EAD.pdf
by the way this trimer is brand new and well would like to know if this mod or any other can be done so it can be turned back / restored to original so if have to be serviced in any way
they dont see notice the mod and the warranty can keep on : ) un afected : )
so j-mac will wait for your posts thanks in avanced
this is my trimer : )
this is not my video
http://www.youtube.com/watch?v=vUStszWi7JY
this is the manual with some parts schematic , maybe that also helps you to see if the mod can be done : )
http://www.hitachi-powertools.com.au/Media/Documents/CG22EAD.pdf
by the way this trimer is brand new and well would like to know if this mod or any other can be done so it can be turned back / restored to original so if have to be serviced in any way
so j-mac will wait for your posts thanks in avanced
gardentec,
You would just be using a lawn mower muffler to act as a silencer. Read the post carefully again. If you buy all the parts I linked you to, they will bolt right on. You can always take them off. There are only 2 bolts holding everything on.
RF Overlord,
Yeah, but the sound pulse is going backwards through the muffler and that is what we are trying to "cancel." I'm not a physicist, but all I know is when you assemble this contraption like I mentioned it is much quieter than with the muffler facing the other direction. I don't know why, but it works!
You would just be using a lawn mower muffler to act as a silencer. Read the post carefully again. If you buy all the parts I linked you to, they will bolt right on. You can always take them off. There are only 2 bolts holding everything on.
RF Overlord,
Yeah, but the sound pulse is going backwards through the muffler and that is what we are trying to "cancel." I'm not a physicist, but all I know is when you assemble this contraption like I mentioned it is much quieter than with the muffler facing the other direction. I don't know why, but it works!
hello mac di you check my trimmer ? gave you the links to see it
, was cheeking the links you gave me an with the mufler link ok its the only one
, but on the other link there are various : / velocity stacks , chokes and air filters : ( so could you please tell me wich of them especifcly i need for the project : D , really looking into making the proyect an now mor that you say i can remove it in case i need to take it to service so that it looks as it came from the store ( mod free ) so warranty keeps on : D , really looking on to making this mod with your help : D
gardentec,
Do you hold the trimmer on your right or left side? If you hold it on your right side, then this contraption may hit your body as you're using it. That is unless you were to use a 90 degree elbow from a radiator hose to turn the assembly toward the rear.
I can't get the manual/schematic to open up. That link is from an Australian site. Are you sure it is the exact same as your machine. The US model may use a different carburetor.
I'll try to figure out the exact parts you need, but I'll need a diagram showing what carburetor your trimmer uses. What is the model number on your trimmer?
-John
Do you hold the trimmer on your right or left side? If you hold it on your right side, then this contraption may hit your body as you're using it. That is unless you were to use a 90 degree elbow from a radiator hose to turn the assembly toward the rear.
I can't get the manual/schematic to open up. That link is from an Australian site. Are you sure it is the exact same as your machine. The US model may use a different carburetor.
I'll try to figure out the exact parts you need, but I'll need a diagram showing what carburetor your trimmer uses. What is the model number on your trimmer?
-John
i would use it on the right side
, my trimmer is a
hitachi CG22EAS slp
this schematic has all th parts it has an its from sears chck this one
http://www.searspartsdirect.com/partsdir...LP/0505/1503820
Originally Posted By: j_mac
gardentec,
Do you hold the trimmer on your right or left side? If you hold it on your right side, then this contraption may hit your body as you're using it. That is unless you were to use a 90 degree elbow from a radiator hose to turn the assembly toward the rear.
I can't get the manual/schematic to open up. That link is from an Australian site. Are you sure it is the exact same as your machine. The US model may use a different carburetor.
I'll try to figure out the exact parts you need, but I'll need a diagram showing what carburetor your trimmer uses. What is the model number on your trimmer?
-John
hitachi CG22EAS slp
this schematic has all th parts it has an its from sears chck this one
http://www.searspartsdirect.com/partsdir...LP/0505/1503820
Originally Posted By: j_mac
gardentec,
Do you hold the trimmer on your right or left side? If you hold it on your right side, then this contraption may hit your body as you're using it. That is unless you were to use a 90 degree elbow from a radiator hose to turn the assembly toward the rear.
I can't get the manual/schematic to open up. That link is from an Australian site. Are you sure it is the exact same as your machine. The US model may use a different carburetor.
I'll try to figure out the exact parts you need, but I'll need a diagram showing what carburetor your trimmer uses. What is the model number on your trimmer?
-John
gardentec,
It looks like the standard bolt pattern Walbro carb. That's good as the aftermarket parts I mentioned will bolt right on. But a potential problem I see is you trimmer has an external primer bulb mounted to the airbox base. I don't know if you could just remove the bulb from the airbox and strap it and the hose to something or if the primer needs to stay with the airbox to work. The bulb may need to stay with the airbox because it might have a port that requires filtered air so it can work reliably. I don't know. I'm not familiar with that setup. Maybe someone can chime in that knows these carbs with the external primer bulb?
You might be able to leave the airbox base in place and put the velocity stack directly against the airbox base IF the surface is flat around the air intake port. Another benefit if you use the stock airbox base is that it LOOKS like it has the choke built into it, so you wouldn't have to fool with rigging up a choke. But all that depends if there is a flat enough surface for the velocity stack to mate up to. Maybe you can have a small metal flange and tube made somehow that will fit onto the stock airbox base? The real problem here is getting something to mate up to the airbox base without having to grind plastic down, since you're wanting to maintain the warranty.
Without detailed pictures of the airbox base, I don't know how much more I can help.
The bottom line is any way you can make that carburetor suck all its air through the exit side of one of the mufflers I linked you to, it will DRAMATICALLY quieten the trimmer down. Any way you can rig it up.
It looks like the standard bolt pattern Walbro carb. That's good as the aftermarket parts I mentioned will bolt right on. But a potential problem I see is you trimmer has an external primer bulb mounted to the airbox base. I don't know if you could just remove the bulb from the airbox and strap it and the hose to something or if the primer needs to stay with the airbox to work. The bulb may need to stay with the airbox because it might have a port that requires filtered air so it can work reliably. I don't know. I'm not familiar with that setup. Maybe someone can chime in that knows these carbs with the external primer bulb?
You might be able to leave the airbox base in place and put the velocity stack directly against the airbox base IF the surface is flat around the air intake port. Another benefit if you use the stock airbox base is that it LOOKS like it has the choke built into it, so you wouldn't have to fool with rigging up a choke. But all that depends if there is a flat enough surface for the velocity stack to mate up to. Maybe you can have a small metal flange and tube made somehow that will fit onto the stock airbox base? The real problem here is getting something to mate up to the airbox base without having to grind plastic down, since you're wanting to maintain the warranty.
Without detailed pictures of the airbox base, I don't know how much more I can help.
The bottom line is any way you can make that carburetor suck all its air through the exit side of one of the mufflers I linked you to, it will DRAMATICALLY quieten the trimmer down. Any way you can rig it up.
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