Quiet generator

Russ, I have a 15KW Westerbeke and have the sound shield around it. With the shield it's pretty quiet, but you can still hear it.

When I got the boat put together in Portland, OR, one thing the boat yard owner suggested I have them install was a generator exhaust water separator. I went along with their suggestion and it's one of the best things I had done to the boat. Essentially what it does is remove the gurgling water (and all the associated noise that comes from it) and sends it out through the bottom of the hull via a thru-hull fitting.

Now, when standing alongside the boat when the gen is running, all you hear is a very well muffled hum from the exhaust. I've had people standing on the dock next to the boat and tell me they couldn't hear it running and didn't see the water gurgling out, so figured I was just running off the inverter.
 
We have a westerbeke 9.6 gas that is also very noisey. I saw in another forum an add for K&B silencers for the gin and also for the mains. Some of the members stated they would not return calls,etc. Hopefully some other members will jump into this that maybe have tried their products or maybe some else's. These are supposed to knock down the noise by close to 40db's. They go into the exhaust to reduce the noise.
 
Interesting, what did a exhaust ter separator cost? I have never heard of it.

Silencers? For the exhaust? How does that work?

I'm not so sure it's the exhaust that is loud, I hear the generator running and in the cabin too. My 370 exits water and exhaust out the side and it could barely be heard. I don't really remember hearing the water or the exhaust for that matter. But I will have to make a point to really listen. Thanks for the responses.
 
Per the K&B website they do not make one for diesel engines as of now but they are in the process of making them and should be out by March.

Stuart
 
I too am curious if anyone has had experience with these "soft" sound shields. I talk to the guy at every boat show (just did at Miami) and I'm hesitant to pull the trigger. My big issue, other than cost, is that on my Westerbeke 10BTD, the seawater pump is on the back side of the genset. You physically can't see the pump. I've learn to change the impeller by using "the Force". If I install the sound shield, I'm affraid that I'd have to remove all the tubing to change the impeller.
 
scubanderson said:
Per the K&B website they do not make one for diesel engines as of now but they are in the process of making them and should be out by March.

Stuart
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Thanks!
LMBoat said:
I too am curious if anyone has had experience with these "soft" sound shields. I talk to the guy at every boat show (just did at Miami) and I'm hesitant to pull the trigger. My big issue, other than cost, is that on my Westerbeke 10BTD, the seawater pump is on the back side of the genset. You physically can't see the pump. I've learn to change the impeller by using "the Force". If I install the sound shield, I'm affraid that I'd have to remove all the tubing to change the impeller.
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That's funny, not sure where mine is but I'm sure I will soon. I would think that the frame stays up but the soft panels must come of easily enough, no? You have seen this in person? Did you ask?
 
I think noise reduction gains by separating the water from the exhaust is going to be generator and boat specific. My westerbeke 8.0BTD is noticably louder without water flowing in the exhaust. In fact, it will wake the dead.

A large part of the noise we get from small diesel engines in generators is the fuel knock and the only way to quieten that is with a shield that encloses the engine. The trade off is you can't see the engine with the shield in place so spotting a leak, a loose belt, etc. is not happening and getting to them for routine maintenance and repairs is complicated.
 
http://www.centekindustries.com/product_descriptions.html

I am in the process of a systematic noise reduction effort on my small boat. I was told the gas water seperator would give the most in terms of decreased sound however I did not have the room to properly install a seperator. I did install a stacked wet exhaust muffler that has an extra chamber compared with the original. It cut my noise by 3-5 db. The people at Centek were very helpful in steering me towards a solution. You cannot order directly from them however. I had to get it from a distributor.

John
 
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Russ Calasant said:
Interesting, what did a exhaust ter separator cost? I have never heard of it.

Silencers? For the exhaust? How does that work?.
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Russ,the total cost for parts was $509 installation was $520. What it consists of is a large "muffler" installed in the engine room. The exhaust from the genset goes into it and magically it takes all the water (and the noise) out of the exhaust and shoots it through a thru-hull. What's left (the gaseous part) of the exhaust goes out through the hull right at the stbd aft corner.

Parts consisted of the Water Separator ("muffler"), hardwall exhaust hose, bronze seacock, bronze thru-hull, and a pipe-to-hose adapter. Eight hours labor to install it.

I'd never heard of it before but I'm sure glad I had it done. There's no exhaust sound, no gurgling sound, nothing heard from outside except a faint whirring sound almost like a fan blade.
 
Gofirstclass said:
Russ,the total cost for parts was $509 installation was $520. What it consists of is a large "muffler" installed in the engine room. The exhaust from the genset goes into it and magically it takes all the water (and the noise) out of the exhaust and shoots it through a thru-hull. What's left (the gaseous part) of the exhaust goes out through the hull right at the stbd aft corner.

Parts consisted of the Water Separator ("muffler"), hardwall exhaust hose, bronze seacock, bronze thru-hull, and a pipe-to-hose adapter. Eight hours labor to install it.

I'd never heard of it before but I'm sure glad I had it done. There's no exhaust sound, no gurgling sound, nothing heard from outside except a faint whirring sound almost like a fan blade.
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Wow, that sounds really cool. I have to go listen to mine again, i only heard it once and all I remember really is that it was surprisingly loud. But I don't remember hearing anything outside other than running water, I think the noise was really inside. Again, not sure.
 
I think you have a BTD Westerbeke....if so, go back and read post #8. The noise you hear is fuel knock and valve lash and a fancy muffler will do nothing to quieten that. A sound shield is your only hope...............
 
I would address (as Frank said "fuel knock and valve lash") before closing the "lid".
 
My westerbeke is a lot quieter than my former gas gen., I have read that it runs at lower rpm's than other brands which helps keep the noise down.
 
fwebster said:
I think you have a BTD Westerbeke....if so, go back and read post #8. The noise you hear is fuel knock and valve lash and a fancy muffler will do nothing to quieten that. A sound shield is your only hope...............
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It is a 6 BTD Westerbeke, I will stick to the sound shield option. Thanks- is there something that needs to be done for the fuel knock and valve lash or is that "normal"?
 
Just my .02: For me, I've have not found the exhaust at the side of the boat to be loud. Matter of fact, I find the splashing noise soothing. And if you don't have water flowing out the exhaust, how do you check water flow <clogged intake, broken impeller, etc>?

As for maintence, Frank is right about potential problems popping up that you may not notice with a shield in place. I met a guy who got rid of his sound shield as it hid a water leak that cost big bucks to fix. It would have been an easy fix if caught earlier

I have seen these things live at the boat shows. The sides and top are easily removable, but the support tubing will be in the way when I try to do waterpump maintenance.
 
There is nothing to fix here, except that Westerbeke has a specified interval for checking the injectors and setting the valves. If you don't know thew history and the noise is bothersome, have your injectors removed and pop tested ($75 + labor) and the valves adjusted. There was a noticable difference in racket when I did that service last summer.

All diesels have a fuel knock and valve lash, some are quieter than others because of the design of the engine. Common rail diesels are noticeably quieter because the fuel knock is minimized by the precise control of the fuel system; valve clearance is also engine specific, the Westerbeke diesel just has a larger clearance than some others.
 
Is there a concern of excess heat when you use a sound enclosure over a generator? I know it's done often, but I would think the genset would tend to run hotter.

Don
 
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