www.iFourWinns.com

Anyone swapped or changed their genset mounts in order to reduce vibration?

The Kohler 5E in our 348 is really loud. The noise is more from transfered vibration than actual combustion noise. I pulled off the sound shield panel and it really wasn't much louder without it. I also checked and noticed the mounts in there now aren't the better anti-vibration mounts Kohler offers for this unit.

So I'm faced with two choices, one is to replace the current mounts with the better ones. The other is to consider remounting the whole thing on anti-vibration mounts. I'll probably be doing the regular mounts first, just to see if they help.

The four factory mounts are mounted to a piece of black starboard, which is in turn screwed to the boat itself. I'm wondering about suspending that whole board on some sort of mounts. If I just raise the genset itself it'd also raise the sound shield. I'd prefer to avoid that if possible, which raising the whole board would accomplish. Of course I have no idea if the board has been glued down or not... but I've asked Four Winns about it and expect an answer, say, next week.

Meanwhile, anyone here care to chime in?

My main concern is figuring out how to do this within the really tight confines of where the genset is mounted. Ya practially gotta be a circus contortionist to get at it. There's about 6 to 8" of extra space vertically and probably a foot horizontally. So I can raise it a good bit if mounts need it. Whether or not I can do that in such tight space is another matter. It seems like it'd be possible with the right combination of sweat, leverage and profanities....

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-Bill Kearney, 2005 348 Vista

http://www.mcmastercarr.com has all sorts of dampened mounts.

Aside from that I can't offer much... Do the mount upgrade and maybe paint all the surrounding areas with sound abatement paint.

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Brett DiMichele

Brett, thanks for the McMaster suggestion. They make some vibration padding material that might be suitable. Their website doesn't allow easy linking but it's on page 1321. They make some out of Nitrile; that's resistant to oil and fuel:



A layer of that under the whole genset mount might be just the ticket. I'll have to look into the weight distribution issues first.

I'm going to start by replacing the existing four mounts from the engine to the platform with Kohler's own higher quality ones. If that's not enough then I'll go with the pad idea. Thanks!

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-Bill Kearney, 2005 348 Vista

This topic couldn't be more relevant for me right now. I've got the 5E as well and it's also very loud; as in from the vibration. When we sleep and lay our heads on the pillows the vibration is transferred through the hull and it is a bit much.

Someone had suggested a sound shield as my 278 has nothing:



If your 348 has a sound shield and it's not doing much I think I may going the same path as you. Obviously the sounds shield isn't going to help vibration anyway, but I figured if I could eliminate some of the sound that might help?

The weight of the 5E is 205lbs without a sound shield and 225lbs with a sound shield; Here's the PDF.

Do you have a photo of the "better" Kohler mounts? Should mine have come with a sound shield?

I'll be watching your progress with this.

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SOLD! 2006 30th Anniversary Vista 278
"Conch'd Out!"

http://vista278.com

Kohler has a kit with better dampers . I don't have a picture of them. The documentation for the kit mentions them as being one set in yellow, the others in green. Given the ones in our 348 are tan colored I'm going under the assumption that these are not the the better ones.

Putting the sound shield around it does not look like a simple job. For one thing there's a base that has to go under the entire genset. Just wiggling that into place would be a hassle. It doesn't seem to take much more room than just the bare genset. But it does look like you'd have to disassemble at least part of the genset to install it. The control box is 'outside' the shield. Retrofitting it would definitely require removing all hoses and wires. It might even require pulling the whole thing. If I were you I'd start with better dampers first and see how it goes.

I've found another website that has dampers. http://www.avproductsinc.com Paul got back to me right away with a quote. He recommended their BRB 60-40 mounts at $24 each (4 needed). The ones look similar to some on the McMaster website and priced about the same. So I may just go ahead and order some instead of the Kohler kit.

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-Bill Kearney, 2005 348 Vista

I guess the complexity of it is why I just got a quote of $1000.

I do believe I'd be better served dampening the vibration as you're planning to do. I will, however, allow you to try it first and report back.

For $100 you don't have much to lose considering how they're mounted now.

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SOLD! 2006 30th Anniversary Vista 278
"Conch'd Out!"

http://vista278.com

Indeed, $100 is cheap enough, parts-wise. The trouble is my genset HAS the sound shield and it looks like the outside mounts are going to be a BITCH to replace. I'm going to assess just what it'll take to get to them first and then order the mounts. I'm hoping it'll only be a matter of contorting myself into the space and not having to pull off anything from the port engine (muffler, manifold, etc)

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-Bill Kearney, 2005 348 Vista

You know, in looking at these pics a little closer it appears as though I have no dampners at all?

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SOLD! 2006 30th Anniversary Vista 278
"Conch'd Out!"

http://vista278.com

You've got some, look at the lower left of that picture. See the ground strap? Just diagonal from that is the mount. It's the tan colored rubber ring under the bolt. Not exactly a 'generous' amount of cushioning, is it? But that's Kohler's standard mount for this genset. My plan is to replace them with better units.

You're lucky, you can get to both ends of yours. The sound shield only lets me see one of the mounts. I'll have to peel off a bit of it to even get to the one on the side that's accessible. How I'll get to the outside mounts near the hull is a puzzle I've yet to figure out. I'm not guessing it'll be easy. Just as long as I don't end up with stitches in my toe again! You really have to watch out for the tabs on the ends of hose clamps when you're climbing up outta the engine compartment.

The kohler website has PDF docs that show the mounts.

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-Bill Kearney, 2005 348 Vista

Bill,

Glad the link was helpful... Mcmaster Carr is like "the" place to go for anything machinery wise.

I think what you need is a mount with a lower durometer factor which means it will be more jiggly (yep that's my technical term) and should absorb more vibration. I also beleive it would be a good idea to paint over all the areas around the genset (the gelcoat, the genset sheild) with a good acoustical paint. The problem is that you will add weight as the paint is heavy to deaden the sound.

Another tip may be to run the genset full bore (if you can turn the govener off and just run it WFO) because at WFO it's a higher frequency vibration and higher frequency sound waves do not propegate to the same distance as low frequency. When I run my 2000i on the swim platform, on Eco throttle it's a very low RPM and it just drones all through the boat, it's not even "engine noise" it's just raw vibration. But at full bore the vibrations stop..

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Brett DiMichele

Good tips Brett.

I don't know that I've found a throttle setting for the Kohler. I don't know that I've ever heard it run at anything other than one RPM range. I usually just have it on only for the blender, the coffee maker or the AC system. Or to bring the ships battery back to life in the middle of the night when the chartplotter anchor watch has drained it to the point the CO alarms trip due to low voltage.... but that'll stop now that I've got the added batteries (he says with naive hope...)

I don't think paint will work. The engine compartment isn't really setup in a way that'd make it anywhere near practical to paint it. If I ever repower this vessel it'd certainly be something to consider. But until then, probably no painting. But I may try putting some hand pressure on the outside of the gunwale adjacent to the genset the next time it's on and I have competent help aboard. If putting pressure on the hull stops some of the vibration then you may well be on to something. It'd still be way too much hassle to paint behind it though...

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-Bill Kearney, 2005 348 Vista

Bill,

Yes indeed it would be a pain to paint that area. Looking at Shan's setup I would imagine removal of these Gensets would be an arduous task at best.

I don't beleive I would even attempt it unless I was doing a repower down the road. And that's a long way down the road!

I hope that the varying durometer mounts you ordered will help quelch the transfer of low frequency vibration and I beleive they will help a great deal.

Shan,

Thanks for posting those photos! It looks like I actually COULD squeeze a westerbeke 3.0KW in my starboard side gunnel after all..... I would have to completely relocate my fresh water tank though... Hrmmm.. May be a future project!

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Brett DiMichele