Another soundproofing thread... the RAAMat experience

[Mainah]

I had planned to use professional two part spray in truck bed liner and go nuts with it around the engine bay, bilge, and long spans of hull walls that are not see. I chickened out on that idea for fear of a giant mess and something that was not removeable.

I did use Noico products from amazon because as with many things the factory likely produces many brands. The MLV is good stuff and very adhesive. The foam is less adhesive and the sheets are smaller. I would not use the noico foam again unless bought as a roll instead of sheets.

I got real cozy with every nook and cranny with my recent mod fest. There is a giant gap between the bilge and each storage compartment that I fillied with CLF packing material then covered that whole fiberglass panel with MLV. That plywood engine bay leaks sound like crazy. I tore the carpet off and used the mlv. I used a bit of spray foam on the larger gaps at the top. I stuffed some closed cell foam packing matering in the larger top hole that leads from the engine bay in the fuel tank. I stuffed 3 oversized 6 inch diameter pool noodles in the fuel hatch as baffling and put MLV on the underside of the hatch. I wrapped the resonators in MLV but chickened out on wrapping the water boxes. I used some MLV on some larger panels hull panels. My foam, epoxy, and mlv sealed inhull sub boxes at the mid cabin should also make a difference being a baffle in the large inner and outer hull gap.

I plan to test with a sound spectrum analyzer soon. I don’t know how much it all helped yet because I was too buzy cranking my redone sound system. I did a terrible job of getting photos of the sound proofing ... no photos at all sorry.

 

[Sebastian]

Thanks for the super fast response guys.
I will definitely look into what @Mainah did.
@Mainah what is CLF packaging?

I remember reading in another thread somewhere that the steering cable introduces vibration and I can for and feel vibrations at my feet in the driver's seat around 3000rpm or so, so I'm planning to look into wrapping the cables into pipe insulation or something like that.

Also, forgot to add to the list, already ordered the garage door rubber that the original thread refers to for the hatch perimeter.

 

[Mainah]

Thanks for the super fast response guys.
I will definitely look into what @Mainah did.
@Mainah what is CLF packaging?

I remember reading in another thread somewhere that the steering cable introduces vibration and I can for and feel vibrations at my feet in the driver's seat around 3000rpm or so, so I'm planning to look into wrapping the cables into pipe insulation or something like that.

Also, forgot to add to the list, already ordered the garage door rubber that the original thread refers to for the hatch perimeter.

Sorry ahould have been ccf (closed cell foam) like cheepo sleeping mats and the like. I did use some foam rubbber weather stripping around the engine hatch and the cabin storage compartment seats too.

 

[swatski]

Thanks for the super fast response guys.
I will definitely look into what @Mainah did.
@Mainah what is CLF packaging?

I remember reading in another thread somewhere that the steering cable introduces vibration and I can for and feel vibrations at my feet in the driver's seat around 3000rpm or so, so I'm planning to look into wrapping the cables into pipe insulation or something like that.

Also, forgot to add to the list, already ordered the garage door rubber that the original thread refers to for the hatch perimeter.

One thing with 19' is they have comparatively more free and open space in the stern, rear compartments and swim deck. Huge open spaces that make parts of the hull there act like giant sound boxes!

Some of those spaces can be used to storage, but a lot of it is just dead space - if you can fill it up with anything acoustically absorbent - it will help more than most other soundproofing mods.

For example, a pair of old ballast bags stuffed and inflated into those stern compartments in the back - will do wonders blocking engine noise and vibration from propagating.

--

 

[Sebastian]

Thanks for the great info guys.
All good points that I have to look into, piece by piece.

The storage I intend to keep as storage, but if it is a pure resonator, there might be other ways (egg-shell...) or I might decide to live with what I can get without compromising storage. There's a couple good tips to start with.
But will have to look underneath the swimplatform as soon as the boat is in my driveway. Had some snow flurries here in Michigan today

Has any of you ever looked at the steering noise topic or not a problem for you?

 

[swatski]

I might decide to live with what I can get without compromising storage.

I would not compromise storage! But there are spaces that are basically voids - if you look at the back of the rear storage and up under the hull cap.
What I noticed is that in the new 240 Yamahas they designed smaller storage compartments accessible from the swim deck into those voids - increasing storage and breaking down those resonating sound boxes/soundproofing the hull at the same time. That leaves a lot less space, relatively speaking, to install integrated ballast etc. but on balance is a brilliant design move.

--

 

[Sebastian]

Honestly, I did not pay attention to that area yet, but will have to have a detailed look.
That might then be a good spot for the egg crate stuff, will have to have a look.
Boat is still in the garage, will probably take another 2 or 3 weeks till it comes out.

 

[adrianp89]

I had planned to use professional two part spray in truck bed liner and go nuts with it around the engine bay, bilge, and long spans of hull walls that are not see. I chickened out on that idea for fear of a giant mess and something that was not removeable.

I did use Noico products from amazon because as with many things the factory likely produces many brands. The MLV is good stuff and very adhesive. The foam is less adhesive and the sheets are smaller. I would not use the noico foam again unless bought as a roll instead of sheets.

I got real cozy with every nook and cranny with my recent mod fest. There is a giant gap between the bilge and each storage compartment that I fillied with CLF packing material then covered that whole fiberglass panel with MLV. That plywood engine bay leaks sound like crazy. I tore the carpet off and used the mlv. I used a bit of spray foam on the larger gaps at the top. I stuffed some closed cell foam packing matering in the larger top hole that leads from the engine bay in the fuel tank. I stuffed 3 oversized 6 inch diameter pool noodles in the fuel hatch as baffling and put MLV on the underside of the hatch. I wrapped the resonators in MLV but chickened out on wrapping the water boxes. I used some MLV on some larger panels hull panels. My foam, epoxy, and mlv sealed inhull sub boxes at the mid cabin should also make a difference being a baffle in the large inner and outer hull gap.

I plan to test with a sound spectrum analyzer soon. I don’t know how much it all helped yet because I was too buzy cranking my redone sound system. I did a terrible job of getting photos of the sound proofing ... no photos at all sorry.

I anticipate the MLV results. I was thinking if I did the whole engine compartment, it could make a huge difference.

 

[Mainah]

Hoping to test this soon. Based on my ear alone I would say even after everything I did I would say there is only marginal but noticeable improvement. My guess is that most of it came from filling gaps as opposed to the mlv. My ear is not a bad tester as I have a very hard time with seperating background noise from foreground noise. I had a slightly easier time carrying a conversation at crusing speed. I was exposed to losts of extremely loud occupational noise across many frequencies in my late teens and early 20s.

 

[Sebastian]

Any ideas for attaching the mats on top of the carpet? Would this be removable? Or do I need to cut the carpet off and glue the carpet back on?

 

[swatski]

Any ideas for attaching the mats on top of the carpet? Would this be removable? Or do I need to cut the carpet off and glue the carpet back on?

If you are talking about the fuel tank hatch etc. - most members here insulate under.
Many chose to install SeaDek which replaces the carpet and is glued to the deck and hull cap.

--

 

[Sebastian]

Sorry, I was not specific enough here... I meant the storage compartments on the side of the engine / wood engine walls, which are covered with carpet.
Planning to do fuel tank hatch and ski locker wall for sure.

 

[LukePrinsloo]

I've been doing a lot of reading on this lately, coming from a engineering background, sound is energy traveling in waves.
The best way to stop sound is to stop those waves. Each frequency responds better to different media. If my motors are out of sync 50 rpm I have a HORRID harmony issue. I am hoping with the introduction of additional sound deadening I can isolate the cause while also reducing overall decibels. Or at least move them lower in frequency.

The below are several thoughts I have running around in my head.

Has anyone ever walked around the boat while underway? I have while trying to find high spots of vibration. The biggest ones were on the swim platform. I could feel my 300 lbs vibrating back there. This makes sense since the jets attach to this back "transom" and the exhaust water boxes are located close by. I feel like this back platform is the initial vibration that gets carried to most of the boat through the guitar like hull.

I feel like an "insulated" box that covers the motors in the engine bay, and one that covers the exhausts by the clean out ports should help with the noise.
Currently contemplating how that would look. (if anyone has a picture handy of what it looks like under the clean out port tray I'd appreciate it, my googlefu was weak in this.) This is similar to what everyone is doing to the engine cover and to the sides of the boat (where there is nothing blocking noise.) However I want to do it as a separate inner box out of something dense like oak plywood (marine grade osb?). It is amazing how much the engine cover of a ski boat reduces noise. Thanks to carpet, fiberglass, foam and then vinyl. I'd duplicate that around each motor. carpet, butyl rubber, box, carpet again.

One thing I noticed about @swatski 's method is that he did the rubber on the fiberglass then the foam. Most of the commercial pre layered actually has rubber first, then foam, then rubber again on the hull. I feel like the first rubber stops certain frequencies and is damped by the foam which then absorbs others and reduces more before it hits the final layer of rubber which is there to add mass to the object being insulated. Granted they usually have 2" of foam between the layers too.

I grew up in a 1991 Supra Combrio open bow, 1996 Nautique Body Glove and a 1998 28 ft regal. This boat (My 2011 is the only yami I've ridden in) is too loud by several decibels. Not being able to talk to people while cruising or hear the music is asinine. During my test drive I was too excited to notice and it was not the longest ride. Every ride since it stresses me out rather than lets me enjoy the boat. I had horrid vibration which turned out to the be shaft bearing (next to the coupler). I did not replace the guibo shaft coupler, though I did notice a LOT of play in it but had no go by to decide if it was enough or too little.@swatski you mention doing so, was that to a new version? different material? I have replaced one of these and plan on replacing the other this winter for good measure.

Jet drive cone bearings: I'm going to try the oil bath mod of Bruce's this winter. He reported a reduction in noise when doing so. Mine feel "tight" which is how a bearing should feel but I do wonder if "looser" freer spinning bearings might not help transmit noise. I also wonder how "balanced" the impeller shaft is. As any imbalance in the shaft would be transmitted through the bearings to the hull.

EDIT: Just Found Ronnie's thread Swatski mentioned in the past.
http://yamahajetboaters.com/forum/viewtopic.php?f=1&t=27553&hilit=+sound+proofing
Posting it here for prosperity. this is something I am very interested in trying (right now).

 

[d_coyne1984]

I've been doing a lot of reading on this lately, coming from a engineering background, sound is energy traveling in waves.
The best way to stop sound is to stop those waves. Each frequency responds better to different media. If my motors are out of sync 50 rpm I have a HORRID harmony issue. I am hoping with the introduction of additional sound deadening I can isolate the cause while also reducing overall decibels. Or at least move them lower in frequency.

The below are several thoughts I have running around in my head.

Has anyone ever walked around the boat while underway? I have while trying to find high spots of vibration. The biggest ones were on the swim platform. I could feel my 300 lbs vibrating back there. This makes sense since the jets attach to this back "transom" and the exhaust water boxes are located close by. I feel like this back platform is the initial vibration that gets carried to most of the boat through the guitar like hull.

I feel like an "insulated" box that covers the motors in the engine bay, and one that covers the exhausts by the clean out ports should help with the noise.
Currently contemplating how that would look. (if anyone has a picture handy of what it looks like under the clean out port tray I'd appreciate it, my googlefu was weak in this.) This is similar to what everyone is doing to the engine cover and to the sides of the boat (where there is nothing blocking noise.) However I want to do it as a separate inner box out of something dense like oak plywood (marine grade osb?). It is amazing how much the engine cover of a ski boat reduces noise. Thanks to carpet, fiberglass, foam and then vinyl. I'd duplicate that around each motor. carpet, butyl rubber, box, carpet again.

One thing I noticed about @swatski 's method is that he did the rubber on the fiberglass then the foam. Most of the commercial pre layered actually has rubber first, then foam, then rubber again on the hull. I feel like the first rubber stops certain frequencies and is damped by the foam which then absorbs others and reduces more before it hits the final layer of rubber which is there to add mass to the object being insulated. Granted they usually have 2" of foam between the layers too.

I grew up in a 1991 Supra Combrio open bow, 1996 Nautique Body Glove and a 1998 28 ft regal. This boat (My 2011 is the only yami I've ridden in) is too loud by several decibels. Not being able to talk to people while cruising or hear the music is asinine. During my test drive I was too excited to notice and it was not the longest ride. Every ride since it stresses me out rather than lets me enjoy the boat. I had horrid vibration which turned out to the be shaft bearing (next to the coupler). I did not replace the guibo shaft coupler, though I did notice a LOT of play in it but had no go by to decide if it was enough or too little.@swatski you mention doing so, was that to a new version? different material? I have replaced one of these and plan on replacing the other this winter for good measure.

Jet drive cone bearings: I'm going to try the oil bath mod of Bruce's this winter. He reported a reduction in noise when doing so. Mine feel "tight" which is how a bearing should feel but I do wonder if "looser" freer spinning bearings might not help transmit noise. I also wonder how "balanced" the impeller shaft is. As any imbalance in the shaft would be transmitted through the bearings to the hull.

EDIT: Just Found Ronnie's thread Swatski mentioned in the past.
http://yamahajetboaters.com/forum/viewtopic.php?f=1&t=27553&hilit=+sound+proofing
Posting it here for prosperity. this is something I am very interested in trying (right now).[/QUOTE

I believe you are on the right track. I have used open cell foam sheeting to create partitions in the rear of my boat which I think has made a noticeable difference. Open cell might not be the best material given the humidity you face, but I have not had any issues with it molding and I think it is the best material at slowing down those sound waves short of stuffing the back with fiberglass batt insulation (which could obviously be a messy situation). I just made sure to keep it away from the bottom and other areas that are likely subject to the occasional water. Insulating the back of the rear storage compartment also makes a big difference. The one thing that was very obvious to me was the frequency change of the noise that does still persist after the insulation. It is a a bit lower than it used to be and is less draining on the ears IMO. I have not done anything to my engine compartment as of yet FYI. I think the bigger problem is the rear of the boat, but most focus on the engine instead.

 

[GTBRMC]

I've been doing a lot of reading on this lately, coming from a engineering background, sound is energy traveling in waves.
The best way to stop sound is to stop those waves. Each frequency responds better to different media. If my motors are out of sync 50 rpm I have a HORRID harmony issue. I am hoping with the introduction of additional sound deadening I can isolate the cause while also reducing overall decibels. Or at least move them lower in frequency.

The below are several thoughts I have running around in my head.

Has anyone ever walked around the boat while underway? I have while trying to find high spots of vibration. The biggest ones were on the swim platform. I could feel my 300 lbs vibrating back there. This makes sense since the jets attach to this back "transom" and the exhaust water boxes are located close by. I feel like this back platform is the initial vibration that gets carried to most of the boat through the guitar like hull.

I feel like an "insulated" box that covers the motors in the engine bay, and one that covers the exhausts by the clean out ports should help with the noise.
Currently contemplating how that would look. (if anyone has a picture handy of what it looks like under the clean out port tray I'd appreciate it, my googlefu was weak in this.) This is similar to what everyone is doing to the engine cover and to the sides of the boat (where there is nothing blocking noise.) However I want to do it as a separate inner box out of something dense like oak plywood (marine grade osb?). It is amazing how much the engine cover of a ski boat reduces noise. Thanks to carpet, fiberglass, foam and then vinyl. I'd duplicate that around each motor. carpet, butyl rubber, box, carpet again.

One thing I noticed about @swatski 's method is that he did the rubber on the fiberglass then the foam. Most of the commercial pre layered actually has rubber first, then foam, then rubber again on the hull. I feel like the first rubber stops certain frequencies and is damped by the foam which then absorbs others and reduces more before it hits the final layer of rubber which is there to add mass to the object being insulated. Granted they usually have 2" of foam between the layers too.

I grew up in a 1991 Supra Combrio open bow, 1996 Nautique Body Glove and a 1998 28 ft regal. This boat (My 2011 is the only yami I've ridden in) is too loud by several decibels. Not being able to talk to people while cruising or hear the music is asinine. During my test drive I was too excited to notice and it was not the longest ride. Every ride since it stresses me out rather than lets me enjoy the boat. I had horrid vibration which turned out to the be shaft bearing (next to the coupler). I did not replace the guibo shaft coupler, though I did notice a LOT of play in it but had no go by to decide if it was enough or too little.@swatski you mention doing so, was that to a new version? different material? I have replaced one of these and plan on replacing the other this winter for good measure.

Jet drive cone bearings: I'm going to try the oil bath mod of Bruce's this winter. He reported a reduction in noise when doing so. Mine feel "tight" which is how a bearing should feel but I do wonder if "looser" freer spinning bearings might not help transmit noise. I also wonder how "balanced" the impeller shaft is. As any imbalance in the shaft would be transmitted through the bearings to the hull.

EDIT: Just Found Ronnie's thread Swatski mentioned in the past.
http://yamahajetboaters.com/forum/viewtopic.php?f=1&t=27553&hilit=+sound+proofing
Posting it here for prosperity. this is something I am very interested in trying (right now).

Strongly suggest you try a hatch perimeter seal before doing ANYTHING else. See @swatski 's post on his method near the bottom of page 1 on this thread. I did this on my '08 SX-230, using a self-adhesive (peel-n-stick) bulb seal from McMaster-Carr, and it was night and day improvement. Cost ~$20, required a pair of scissors, some rubbing alcohol and cotton balls to prep surfaces, and no more than 30 minutes to apply.

My bulb seal method lasted about 2 seasons before re-application was needed. $20 and 30 mins for 2 seasons of MUCH reduced noise in the cabin was certainly worth it for me.

Notes: I don't know how similar the air gaps around the hatches (when latched) are from model to model, so your results may vary... and I am also a mechanical engineer by training, so I appreciate simple, effective, fast, low cost fixes.

 

[LukePrinsloo]

Just Ordered a DB meter. I'm going to try be the first person to do this step by step. New thread to come after I've done a few steps.

 

[swatski]

Post #19 here has the engine hatch seal info:
https://jetboaters.net/threads/another-soundproofing-thread-the-raamat-experience.11872/

And here is one of my new tricks:
https://jetboaters.net/threads/major-source-of-engine-noise-2015-242.16465/#post-330321

@LukePrinsloo I admire your enthusiasm, we need to come up with a better soundproofing algorithm!!!
I don't know if a dB meter is going to tell you more than your ears.
I know quiet when I hear it! (not) lol

--

 

[LukePrinsloo]

I actually bought the engine hatch seal months ago, and just felt like it was a placebo and never installed it. I'll take it and the glue with me this weekend. (and the db meter.)

also see this thread: https://jetboaters.net/threads/engine-noise-while-riding.19246/

My noise might be more than most.

 

[GTBRMC]

I actually bought the engine hatch seal months ago, and just felt like it was a placebo and never installed it. I'll take it and the glue with me this weekend. (and the db meter.)

also see this thread: https://jetboaters.net/threads/engine-noise-while-riding.19246/

My noise might be more than most.

Depending on your dB meter, of course, it would be great if you could get various position (within cockpit) x various rpm x various frequency readings before and after each soundproofing action you take.

Looking forward to your results.

Edit: I just realized I signed you up for a load of work, feel free to ignore, LOL.

 

[LukePrinsloo]

My biggest issue will be kids in the way.
I'm hoping to have a fun day on the lake, drop kids off at the landing with Granny and then with three people in the boat take my first measurements.
Bow seat (left/right), driver's seat with folded seat down on passenger side, passenger side (still folded), then behind driver, and lastly left right side of the swim deck.
I'll probably do this at ~10-20mph. (cruising speed for us), above that the wind noise is most of the noise.

However, i will warn that I think I have a bent driveshaft and as such that may extend/preclude these tests. I'm |<>| close to just trading it in on a new (2018) Ar240. If so I'll try the same things. (After I fix it, if it is broken.)