Sound Insulation, Different Approach, Harmonics off swim deck and water box noise

[granpachuck]

@granpachuck
It has been a few years. But from Memory the difficult part is disassembling. Not much room for movement and all hoses are kinda stuck. Reassembly went much easier. Disassembly was rough

Thank you, I think, for the confidence to keep going. Got starboard side box out and am now using a combination of Kilmat, Noico , and some cheap memory foam . The foam is for the upper corners I am not going to be able to reach. Slow going. I don't know if I will have the energy to start the port side ...
The water box wouldn't fit out of the hatch, so I had to grind the opening a bit larger, and I think I will give it a wrap after I place it back in, but before I connect the hoses back up to it.
Our lakes here are at flood levels, so this is a good time to work on it in my driveway.

 

[AZMark]

Thank you, I think, for the confidence to keep going. Got starboard side box out and am now using a combination of Kilmat, Noico , and some cheap memory foam . The foam is for the upper corners I am not going to be able to reach. Slow going. I don't know if I will have the energy to start the port side ...
The water box wouldn't fit out of the hatch, so I had to grind the opening a bit larger, and I think I will give it a wrap after I place it back in, but before I connect the hoses back up to it.
Our lakes here are at flood levels, so this is a good time to work on it in my driveway.

How did this end up going @granpachuck? Did you get it all back together ok and was there a lot of difference? Thinking of tackling this during the off season.

 

[granpachuck]

How did this end up going @granpachuck? Did you get it all back together ok and was there a lot of difference? Thinking of tackling this during the off season.

Hi, yeah it helped some, but the truth is there has been no one thing that made a huge difference so far. Each sound project seems to have incremental improvement. Of course, the engines are deadly quiet now; put a nice hole in the bottom of the boat right before labor day. Hit a submerged tree stump I think.
I am not done finding ways to quiet her down, and reduce vibration. I added a few pics, one of the waterbox wrapped with Kilmat and Noico, and partially reinstalled.

 

[AZMark]

Hi, yeah it helped some, but the truth is there has been no one thing that made a huge difference so far. Each sound project seems to have incremental improvement. Of course, the engines are deadly quiet now; put a nice hole in the bottom of the boat right before labor day. Hit a submerged tree stump I think.
I am not done finding ways to quiet her down, and reduce vibration. I added a few pics, one of the waterbox wrapped with Kilmat and Noico, and partially reinstalled. View attachment 134409View attachment 134409View attachment 134410

Thanks. Looks good!
Sorry to hear about the hole in your boat.

 

[d_coyne1984]

Hi, yeah it helped some, but the truth is there has been no one thing that made a huge difference so far. Each sound project seems to have incremental improvement. Of course, the engines are deadly quiet now; put a nice hole in the bottom of the boat right before labor day. Hit a submerged tree stump I think.
I am not done finding ways to quiet her down, and reduce vibration. I added a few pics, one of the waterbox wrapped with Kilmat and Noico, and partially reinstalled. View attachment 134409View attachment 134409View attachment 134410

I would highly recommend adding some softer materials back there. Mass loading doesn't work on boats like it does in cars. The more air space you can take up back there the better. That cavity acts like a drum. If you want to test it, stuff a few old pillows through the holes.