Water Box, exhaust, material for insulating????

[dan144k]

Started taking out the waterbox to work on aerator ballast pump install, the hoses are very difficult to get off the water box FYI.

Considering insulating the waterbox while out of the boat, hoping it will reduce noise.
I have some knukoncept knoknoise (like dynamat) and I am considering wrapping the waterbox with.

Anybody insulate a waterbox before??? Ideas, suggestions???

Also gonna add some product on inside of hull where exhaust exits, and in are where swim deck extends out from boat, While I have it open and exhaust out of the boat.

 

[GTBRMC]

Suggest you verify operating temps the wrap can tolerate...I believe those water boxes can get hot.
Also, consider any affect a wrap could have in reducing the boxes' ability to shed heat.

 

[dan144k]

Also noticed a round plastic baffle type (expansion chanber) item between the waterbox and exhaust outlet.

Looked up the 2015 parts sheet and compared part numbers. The new 2015 have a different waterbox and square type baffle now using different part numbers then 2010.

 

[buckbuck]

dan,
Years ago I wrapped my waterboxes with some scrap Hydro Turf I had laying around. I am not sure it made much difference and I failed to consider what GTBRMC brought up. We also have different engines.

 

[dan144k]

I am thinking of maybe just putting some strips of insulation on the waterbox. The thin dense multi-layer material, to absorb and cancel some resonance and harmonics. There also are the plastic resonators in the exhaust system, but I am concerned f I insulate those the plastic may melt. Still throwing around ideas. I posted a question on greenhulk, so see if that produces anything. I have a few days until I put everything back together.

 

[Speedling]

My waterbox runs about 110-120 degrees right after a high speed run. Remember there is water cooling everything off that ends up in there. There is a simple rubber hose connector attaching the exhaust and also after the waterbox those are all just plain rubber. So, it should be fine but if you do it, you would be wasting your time. It would dampen sound better by putting under the hatch door to your cleanout plugs,or an extra layer under the engine hatch behind the seats. SSeriously, think of how loud it is behind the boat. Pay attention to the type of noise. Is the noise coming out the exhaust pipe? I think the noise out the back is different than what is getting into the cockpit.

 

[txav8r]

I haven't attempted to tackle the noise factor, but to me, it is all engine noise at speed. The exhaust noise goes through so many turns and is water cooled to the point of no issue I think. The noise, at least to me, is coming from the engine compartment, not in the clean out compartment. But agree with @Speedling that the temps of the water boxes is a non issue and they are not hot by exhaust standards.

 

[dan144k]

I think most of the noise is from the rear of boat and from the exhaust. It gets much louder when you go on plane and the boat comes put of the water.

I have the material and plan to do engine compartment also.

 

[dan144k]

New thought idea. If I insulate the waterbox, the exhaust sound will simply be increased and send out the rear exhaust of the boat. So I am just gonna insulate the rear compare,ext and try to absorb the noise more, VA sending more noise outside the boat.

 

[tdonoughue]

Not sure that I follow the physics of insulating the waterbox leading to increased sound. Sound insulation (especially the heavy mats you are discussing) works by presenting extra mass for the sound waves to move in order to pass though. That takes more energy, which leads to less energy coming through on the other side. Meanwhile, the surface to which it is adhered also has more mass and cannot resonate at the same frequency and will take more energy to do so.

If you were replacing the waterbox with a ceramic one or something with a hard, reflective surface, then you might enhance the sound out the back. But beyond that, I don't think you need to worry about the waterbox insulation increasing noise out the back.

 

[dan144k]

@tdonoughue thanks for the input. I was arguing the physics in head both ways. Your explanation is very logical.

 

[Speedling]

Wont increase noise but insulation on the box won't really decrease it either

 

[tdonoughue]

Well, I think it may reduce exhaust noise. Problem is that I also believe (without any real quantitative analysis) that the engine noise perceived in the cabin is much greater than the exhaust noise...

 

[Glassman]

I've got the noise issue licked, once and for all!!!!

 

[Cobra Jet Steering LLC]

Actually sea doo had a rubber type wrap on their 4 tec water boxes in a couple of G T X skies I owned years ago perhaps you can learn what they were made out of .
The only time a water box gets hot at all is if you don't have water going into it.
Your hot alarm would be triggered before any damage could be done to anything. I would be looking at those exercise mats or the floor mats for below work benches sold in homedepo etc. I have those in front of my welding table an they have not had any issues after years of use.
Most people just insulated the engine compartment to reduce engine noise.

 

[dan144k]

I ended up wrapping my waterbox's about 80% with 1" sounddown. Also put a lot of knoknoise and sounddown into the exhaust compartment area. I need to post pictures when get a chance. I took pictures. It was a lot harder project than I expected. Getting the exhaust hoses apart and back together was aweful. I ended up having room for 5) 1200gph aerator pumps under the waterbox. I only needed 3 but put in 5 of them for future or in case one breaks.

It did make a big difference. Can now have a conversation while tubing without yelling at each other. Wife noticed also.

 

[Trevor Shipman]

I ended up wrapping my waterbox's about 80% with 1" sounddown. Also put a lot of knoknoise and sounddown into the exhaust compartment area. I need to post pictures when get a chance. I took pictures. It was a lot harder project than I expected. Getting the exhaust hoses apart and back together was aweful. I ended up having room for 5) 1200gph aerator pumps under the waterbox. I only needed 3 but put in 5 of them for future or in case one breaks.

It did make a big difference. Can now have a conversation while tubing without yelling at each other. Wife noticed also.

Pics please!

 

[dan144k]

@Trevor Shipman
Pics are in another right up. I can get u a link tonight

https://jetboaters.net/threads/soun...im-deck-and-water-box-noise.7763/#post-134361