noxudol 3100 panacea for engine noise reduction on our Yammies?

[gthh]

Has anyone tried this stuff on their engine compartments? We are currently putting this stuff to dampin the noise on our Cyclones at work. Sounds convincing.

 

[swatski]

Has anyone tried this stuff on their engine compartments? We are currently putting this stuff to dampin the noise on our Cyclones at work. Sounds convincing.

I wouldn't trust the infomercial, but if someone here tries it out and it works - that would be GREAT. There is so much raw fiberglass inside the compartments where that could be sprayed!

Following.

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[Beachbummer]

I added a gasket around the engine access hatch, and when going at speed i can only hear engine noise coming from the swim platform and from behind the boat (exhaust maybe) this is with the carpet on which does have an impact on noise.

Based on this observation I'm discouraged from adding more sound insulation, since the noise seems to be coming from exhaust and rear of boat.

 

[gthh]

Boating season is over for me in Western NY but if this works on our Cyclones I will give it a try and report back.

 

[SamCF]

I added a gasket around the engine compartment. Much less engine noise. Now I hear most of the noise coming from the ski and fuel compartments. I think it's vibration from the impeller vibrating and making the high pitch noise we hear thru those compartments.

When I first repitched my stock impeller, it was smooth and quiet. Following impellers and pitches have not been as smooth, and noise increased with the vibration.

I think a sound deadning material would help dampen these vibrations.

If vibration/noise is a big problem, you might want to pull your impeller and check it out. Small dings can be filed out easily, or you can send it to Impros or Skat for a repair job. Don't be scared of pulling the pump, it's not hard at all.

@swatski tried different impellers on his 190, maybe he could add input on the impeller vibration/noise connection.

 

[swatski]

I added a gasket around the engine compartment. Much less engine noise. Now I hear most of the noise coming from the ski and fuel compartments. I think it's vibration from the impeller vibrating and making the high pitch noise we hear thru those compartments.

When I first repitched my stock impeller, it was smooth and quiet. Following impellers and pitches have not been as smooth, and noise increased with the vibration.

I think a sound deadning material would help dampen these vibrations.

If vibration/noise is a big problem, you might want to pull your impeller and check it out. Small dings can be filed out easily, or you can send it to Impros or Skat for a repair job. Don't be scared of pulling the pump, it's not hard at all.

@swatski tried different impellers on his 190, maybe he could add input on the impeller vibration/noise connection.

I had about 250lbs of sound deadening in my 190. At the end - still far from perfect but - became tolerable.

Indeed, those boats' sterns have acoustics of a guitar box! (unfortunately). The new 240 hulls are much better padded from factory and have all the wet compartments squeezed in there - I think at least in part to break up the acoustics - and it kind of works.

The impeller/wear ring is a big factor. Now - I hate to say it as I know I'm going to catch some flak - the plastic (delrin) wear ring inserts really help with the metallic high pitched impeller sound which resonates throughout those hulls. Not advocating to switch to those! and one also needs to consider the cost of a new wear ring as those are different than the OEM. BUT - if one is after making that boat a little more quiet, those plastic rings really help.

As far as the impellers, the OEM has always been the roughest of the three brands I tested. Skat Trak was the smoothest for cruising, I think.

But as far as performance - I could never get any impeller to perform better than the OEM, overall.
(and I tried like heck)

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[msavold]

Man, that looks interesting.
Here's a document on the stuff: http://www.kaiser-soze.com/documentos/Auson/Noxudol3100.pdf
I was thinking an aerosol can might be an interesting test, but hoo, boy, it would take a lot of spray cans! 1 can covers 1.25 sq. ft. (3 coats) for $27.50 and 1 gallon covers 8 sq. ft. (3 coats) for $125. (BTW, I was trying to see the difference between 3100 and 3010 but haven't found it yet.)
Actually, thinking about it now, even though three coats are recommended, I'd want to check after each coat and see how it's doing... It should be easier to apply than acoustic panels stuck on with an adhesive!

 

[ncnmra]

What material did you guys use for the engine compartment gasket?

 

[swatski]

What material did you guys use for the engine compartment gasket?

https://jetboaters.net/threads/another-soundproofing-thread-the-raamat-experience.11872/

The seal, a walmart special, holds up excellent so far.

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