I have a Coleman PowerMate 5000 portable generator. While the 10HP Briggs motor runs OK and the generator puts out lots of voltage, it is extremely noisy. I have seen a couple of articles that try to quiet them down some using flex tube and a muffler from an automotive shop, I haven't heard one yet that really sounds like it has quieted down. I know there will be motor noise and generator noise, but how do you muffle the thing down so that you at least can carry on a conversation without yelling?
How Do YOu Quiet Down A Noisy Generator?
- Thread starter FatFndr
- Start date
aandpdan
Well-known member
Build a big box.
Leave it big enough so that there is plenty of airflow around the generator. Put a roof on it too. It's not just the exhaust that's noisy. The mechanical noise is pretty loud too.
It won't make it quieter but it will help you direct where the majority of the sound goes.
Leave it big enough so that there is plenty of airflow around the generator. Put a roof on it too. It's not just the exhaust that's noisy. The mechanical noise is pretty loud too.
It won't make it quieter but it will help you direct where the majority of the sound goes.
aandpdan
Well-known member
This is an old picture but it shows the basic idea. I can open the doors wide and even leave the roof angled open.
This is a 10hp Tecumseh 5000 watt.
It does ventilate nicely. Even in 80+ weather I've run it for over 3 hours at a time with no problems, it was about 85 on the box near the flywheel fan using an IR thermometer. I don't run it 24/7. Don't need to.
You could always put a fan in there if you had to.
This is a 10hp Tecumseh 5000 watt.
It does ventilate nicely. Even in 80+ weather I've run it for over 3 hours at a time with no problems, it was about 85 on the box near the flywheel fan using an IR thermometer. I don't run it 24/7. Don't need to.
You could always put a fan in there if you had to.
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kd3pc
Well-known member
box and marine sound deadening panels...will do some good, but the one you have and the ones like it are notorious for noise...
you get what you pay for.
you get what you pay for.
Speedy Petey
Well-known member
Truth. I've seen all sorts of creative ways to quiet down cheap generators, but a better quality unit to start is always easiest, even at the added expense.
I've seen a couple with small car mufflers on them, but they were hacked on.
Charles (in GA)
Well-known member
You need a really long cord. Put it out in the back 40 somewhere. Our HOA has a 10K watt Dayton with a Genrac V twin on it (to power a water well), loud, you can hear it running several hundred feet away. I have a 6500 watt Northstar with a 10 hp Yanmar Diesel. I'll swear you can hear it over in the next county. I've got about 85 ft of 8/4 cord to connect it to the house.
Charles
Charles
JerryC
Well-known member
check youtube. I like the Rubbermaid type sheds that people modify. I was going that route myself but then I decided to put in the shed with the lawn tractor.
There is company that specializes in selling everything but the shed for generator enclosure. Search for Genshed and Powershelter. They are not cheap...
There is company that specializes in selling everything but the shed for generator enclosure. Search for Genshed and Powershelter. They are not cheap...
kd3pc
Well-known member
Careful of CO, unless ventilated or exhaust has been rerouted...
Highbeam
Well-known member
I had a coleman 5850 that I tried to quiet down for years. I added flex to the muffler and then hooked the flex to a factory Yamaha motorcycle muffler with a tiny outlet. It helped slightly but was absolutely not worth it. A long cord helped more.
The fix for you is to buy a better generator. Sell your used coleman for whatever you can get and then buy a better one. I moved to a champion genset for 250$ that makes 240 volts for my whole house backfeed and that thing has been wonderful. Not only much much quieter but it runs over 12 hours on 5 gallons of fuel. That old coleman was a gallon per hour doing the same load.
There is a range of price points with gensets. There is a 7000$ honda that is silent, a champion for only a few bucks more than a super loud coleman. You don't need a honda but you don't want a coleman.
Sell yours and use the proceeds to mostly purchase the new one.
The fix for you is to buy a better generator. Sell your used coleman for whatever you can get and then buy a better one. I moved to a champion genset for 250$ that makes 240 volts for my whole house backfeed and that thing has been wonderful. Not only much much quieter but it runs over 12 hours on 5 gallons of fuel. That old coleman was a gallon per hour doing the same load.
There is a range of price points with gensets. There is a 7000$ honda that is silent, a champion for only a few bucks more than a super loud coleman. You don't need a honda but you don't want a coleman.
Sell yours and use the proceeds to mostly purchase the new one.
sounds like a plan to me.theoldwizard1
Well-known member
An insulated box is the right solution, but it does require some serious thought !
You can build the box out of multiple layers of 1" foam board and cover it with fiberglass. Not too expensive, easy to assemble and waterproof. It will need to be at least 2-4' wider, 2'-4' longer and 2' taller than the generator depending on where the power cord(s) attach and where the exhaust is. The box should be built with legs/supports so that it is at least 6" off the ground.
Heat is your enemy. You should weld/bolt an elbow on to the muffler and run a pipe pointing down to within about 6" of the ground. This alone will be as good as most mufflers. You will need a heat shield on inside across from the muffler/eblow. A piece of 1/8" thick steel mounted with a 2-3" air gap from the foam. In summer, you will have to make a fairly large hole in one end and use a box fan to cool your rig.
You might have to add several 2" holes in the top.
You can build the box out of multiple layers of 1" foam board and cover it with fiberglass. Not too expensive, easy to assemble and waterproof. It will need to be at least 2-4' wider, 2'-4' longer and 2' taller than the generator depending on where the power cord(s) attach and where the exhaust is. The box should be built with legs/supports so that it is at least 6" off the ground.
Heat is your enemy. You should weld/bolt an elbow on to the muffler and run a pipe pointing down to within about 6" of the ground. This alone will be as good as most mufflers. You will need a heat shield on inside across from the muffler/eblow. A piece of 1/8" thick steel mounted with a 2-3" air gap from the foam. In summer, you will have to make a fairly large hole in one end and use a box fan to cool your rig.
You might have to add several 2" holes in the top.
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Barnabas
Well-known member
If you build a box that you do not want sound to go through, you want the walls made out of dense material, like drywall or MDF (brick is better). It's even better if you can leave a small air gap between layers. This is how we do it in recording studios.
Also isolate the generator from the floor with some rubber wheels or rubber pucks.
The soft kind of sound insulation is good for keeping sound from bouncing off walls, but does not keep the sound from going through it.
Be sure to allow air flow to get fresh air in and exhaust out.
Also isolate the generator from the floor with some rubber wheels or rubber pucks.
The soft kind of sound insulation is good for keeping sound from bouncing off walls, but does not keep the sound from going through it.
Be sure to allow air flow to get fresh air in and exhaust out.
Backlight
Well-known member
This guy is an amazing fabricator - he made an very nice enclosure..
Kevin C
Well-known member
I have a Briggs 5HP wood chipper. The motor was getting a little tired so I picked up a fresh block with a new rod and piston. The new block is an iron sleeve (IC block).
Somewhere between the tighter rod , piston and iron liner the new motor is a lot quieter.
The beat up air cooled sound is gone.
For a good motor a better muffler seems like it should help. Prior to that I had no appreciation as to how much of the racket was engine pieces hammering on each other. I think this is pretty common for a lot of older air cooled engines.
nu2me
Member
A few further points:
These engines are noisy by nature because the finned cylinders and heads must have direct access to cooling air.
If your generator has seen only occasional use, (not worn and loose enough that it's using oil), a short-block isn't going to change things. If you do go in that direction, be aware that not any old short-block will do. Generators have a special crankshaft with a long taper, rather than a key on the drive-end -- the long center bolt draws the rotor's seat onto the taper.
I imagine your Coleman used the standard cube-shaped two-bolt Briggs muffler. Better-quality generators, for example, some older Homelite HG's with Briggs I/C's, were equipped with tuned mufflers the size of a small telephone book. These mufflers are furnished by the gennie manufacturer, not Briggs, and do noticeably reduce noise. Because all that weight on the port flange and fasteners acts as a bob-weight, the mufflers are always braced to the generator's end casting or its mounting feet. You might ask small engine service people for more current suggestions.
Generator mounting cushions are also tuned to selectively isolate vibration. Don't substitute with generic shock mounts from Grainger's. (Too rigid -- I've seen two cases where this caused the crankshaft's ball bearing race to wear its mating bore in the aluminum case. Adds a squealing noise to the mix.) Unless crushed-down, cracked or oil-soaked, there's probably nothing to be gained by replacing them.
One point that hasn't been mentioned in connection with enclosures is that fumes from refueling and the unavoidable spillage dissipate before the gennie can be safely fired up. If it's not brushless, there will be opportunities for sparks, aside from the fact that hot exhaust parts can be sources of ignition.
All things considered, it's not worth spending big $$$ on a ten year-old homeowner-quality generator, so try low-buck approaches first. If that doesn't work out and you're thinking about a new unit, the quiet, very expensive inverter models only run as fast as the load dictates. Auto-idle, which reduces speed under no-load conditions, has long been available on commercial-quality units because it reduces fuel consumption. Anything other than a homeowner-quality generator should have overhead valves and a cast-iron cylinder bore for longer life. Honda, Kawasaki, Fuji-Robin, Yamaha, and Briggs Vanguard series are good, and you won't be able to find parts for unknown Brand-X Chinese clones, which also cheat on the business end. You might talk to the people at contractor rental outfits for recommendations.
These engines are noisy by nature because the finned cylinders and heads must have direct access to cooling air.
If your generator has seen only occasional use, (not worn and loose enough that it's using oil), a short-block isn't going to change things. If you do go in that direction, be aware that not any old short-block will do. Generators have a special crankshaft with a long taper, rather than a key on the drive-end -- the long center bolt draws the rotor's seat onto the taper.
I imagine your Coleman used the standard cube-shaped two-bolt Briggs muffler. Better-quality generators, for example, some older Homelite HG's with Briggs I/C's, were equipped with tuned mufflers the size of a small telephone book. These mufflers are furnished by the gennie manufacturer, not Briggs, and do noticeably reduce noise. Because all that weight on the port flange and fasteners acts as a bob-weight, the mufflers are always braced to the generator's end casting or its mounting feet. You might ask small engine service people for more current suggestions.
Generator mounting cushions are also tuned to selectively isolate vibration. Don't substitute with generic shock mounts from Grainger's. (Too rigid -- I've seen two cases where this caused the crankshaft's ball bearing race to wear its mating bore in the aluminum case. Adds a squealing noise to the mix.) Unless crushed-down, cracked or oil-soaked, there's probably nothing to be gained by replacing them.
One point that hasn't been mentioned in connection with enclosures is that fumes from refueling and the unavoidable spillage dissipate before the gennie can be safely fired up. If it's not brushless, there will be opportunities for sparks, aside from the fact that hot exhaust parts can be sources of ignition.
All things considered, it's not worth spending big $$$ on a ten year-old homeowner-quality generator, so try low-buck approaches first. If that doesn't work out and you're thinking about a new unit, the quiet, very expensive inverter models only run as fast as the load dictates. Auto-idle, which reduces speed under no-load conditions, has long been available on commercial-quality units because it reduces fuel consumption. Anything other than a homeowner-quality generator should have overhead valves and a cast-iron cylinder bore for longer life. Honda, Kawasaki, Fuji-Robin, Yamaha, and Briggs Vanguard series are good, and you won't be able to find parts for unknown Brand-X Chinese clones, which also cheat on the business end. You might talk to the people at contractor rental outfits for recommendations.
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wfopete
Well-known member
The low dollar old school military way is to dig a pit and place the offending generator in it. You'll have to come up with a drainage plan for big rains. 
ard
Well-known member
I built a 3 sided concrete block (CMU) building for my pool equipment- open down the valley. Wood/asphalt shingle roof. It'll last forever, replace the roof every 20 years.
3 pumps, 2, 1.5 and 3/4HP.... You can barely hear it once you walk 20 feet up the hill
3 pumps, 2, 1.5 and 3/4HP.... You can barely hear it once you walk 20 feet up the hill