• Welcome to Jetboaters.net!

    We are delighted you have found your way to the best Jet Boaters Forum on the internet! Please consider Signing Up so that you can enjoy all the features and offers on the forum. We have members with boats from all the major manufacturers including Yamaha, Seadoo, Scarab and Chaparral. We don't email you SPAM, and the site is totally non-commercial. So what's to lose? IT IS FREE!

    Membership allows you to ask questions (no matter how mundane), meet up with other jet boaters, see full images (not just thumbnails), browse the member map and qualifies you for members only discounts offered by vendors who run specials for our members only! (It also gets rid of this banner!)

    free hit counter

Compressed video of sound absorbing material installation in engine compartment

Ronnie

Jetboaters Fleet Admiral
Messages
8,775
Reaction score
12,185
Points
667
Location
SF Bay Area
Boat Make
Yamaha
Year
2010
Boat Model
Limited S
Boat Length
24
So the wind and rain kept me from boating to the 4th game of the World Series tonight and I ended up enjoying a lazy day at home.

Here is the subject video I put together today, it's not as clear as @Geoff Cooper 's write-up so if you have any questions just ask.

Note that I ended up reinstalling all of the stock material over the new material as well. This off season I may install more material in the compartment where the water boxes are as well as in specific locations throughout the hull.

 
Last edited:
Have you had a chance to measure the amount of noise that you've been able to block? We are testing with some new materials we found at IBEX and have been experimenting with SPL meters. Anxious to hear how much dB reduction you get.
 
Will,
Are you looking at selling sound reduction kits!?!
 
We are developing one right now.
 
Ronnie,
Have you had a chance to see if it made a difference?
 
My results were weird" in that They were higher than boat test's at idle/no wake rpm but quieter at 4500 and 6500 rpm (and at wot I assume because boat test didn't take a wot reading). In comparison to the 2015 model I think my high rpm results were better as well.

Here is a link to my post on the subject, there are additional pics in the string as well. https://jetboaters.net/threads/my-2014-upgrades.1051/page-5#post-51009

I am just using a $3 db meter app on my iPhone and our testing conditions/parameters will be different so I doubt our readings will yield any meaningful comparisons. my friends and family say it is quieter while we are underway based on the fact that they speak instead of yell at one another now after I've installed the sound absorbing material.

If I were to do it again I would probably go with 2" thick material without the foil face (I.e, additional heat resistance) as that is what it looks like yamaha did at least in part with the 2015 240s although they didn't go as low in the compartment. I suspect they rely on the other new materials they used like the couplers to help deaden or reduce the sound produced by the engines. I saved all of my templates in case anyone wants to do this themselves. As I recall including shipping of 17 linear feet (I.e., 17' x 5') of material my total costs were around $400.
 
Nice job. I did the hinged cover and fuel tank cover on my boat last year and noticed some improvement. I also did not have good meter and used an app on my phone,, so not very accurate readings but I think it sounds better so it has to be better.... I think I still need to do the rear and side walls like you did for better sound insulation which is part of my plans for spring.

One thing I didn't see on your video was the beer breaks... How many beer job was it?
 
I don't drink beer anymore but I did take a break every two hours or so. It took two full days / 16 hours at least to complete the project. This is the second time I've done this so it seemed to go a little faster this time around.
 
Nice! How would one go about borrowing or getting a copy of the templates? I need them for the sides.
 
Great job on the video Ronnie!
 
@ Steined pm me your mailing address an I will try and send it out to you by this weekend.

@Zarrella , thanks for the compliment. The longest part of putting this video together was waiting for the gopro software to process/convert it all. Im staying with windows movie maker for the foreseeable future.
 
Last edited:
I think we are going to sell the raw materials that we've been testing with but are not going to sell a pre cut kit.

The materials that were going to sell are:

Sound Suppression Sheet
Sound suppression Gasket
Sound suppression fire port ring

By installing these items at the front of your engine hatch opening, both top and bottom, you will achieve notable db reduction. How much is undetermined as we have not been able to get measuring equipment to confirm what we're hearing with our ears.
 
@Ronnie : OK video, but I wooda been a lot more impressed if you had video taped ALL 2 days of your work and posted that up for us to watch.

At 2nd thought, even better would be if you'ld fly EAST @ your expense and do the same modification (maybe even a little better) for me and Miss B'Haven !

Waiting to pick you up @ the Atlanta airport, I remain, yours truly, Mikey Lulejian - Living' the good life on Lake Oconee, GA
 
Nicely done!
I know adding the seal around the hatch did a good bit for me. Moreso than the under the hatch insulation I did. I also put 2" construction foam insulation under the seat compartments to further separate the engine bay from the rest of the boat, which actually did a little bit as well. I had some plywood covered in carpet, but mine was in rough shape, so it helped out.
Glad to hear JBP is working on stuff as well.
 
Back
Top