Engine Room insulation

The friendliest place on the web for anyone who enjoys boating.
If you have answers, please help by responding to the unanswered posts.

Edelweiss

Guru
Joined
May 15, 2011
Messages
1,860
Location
USA
Vessel Make
1976 Californian Tricabin LRC
My original Californian engine room insulation is beginning to look tired. *Anybody else replaced their's and what was your source? *I don't seem to find the same materials that Marshall used around anywhere. (It had a metalic surface and probably contained lead,
bleh.gif
*) *I have seen some simular looking material, but appears to be a mylar surface.
 
I had done some research on this a couple of years back considering the same thing. It's noisier than I like in the salon and I'd like to correct that. But, like many improvements, it's been placed on the back burner. My thought was to apply the barrier on TOP of the floor and below the carpet pad to make the installation easier. Besides, I didn't think I'd need more soundproofing under the cabinets and settee.

Here's the stuff I looked at. http://www.soundown.com/index_Marine.htm

The folks at Sounddown sent me samples to consider. I don't recall if any of their material would be suitable for this type of installation.
 
Sounddown is a great source.* Also consider acoutic cork as a first layer.* It does quite a bit to quiet things down.
 
Thanks Flywright:

Soundown has lots of products alright and I would bet they have something like I'm looking for. Reading their web site literature sounds like they have an inflamable aluminized fiberglass insulation, but their pictures are generic and not in color, so hard to tell. *I will have to contact them.*

Maybe the 34's engine room are a little different since they are in the stern. *The 37/38/42's have a midship machinery room which is completely lined with a 1' layer of fiberglass insulation that is aluminum faced, ceiling, the hull and all bulkheads. *I was hoping to find something like the original to replace it. *I found something simular in the commercial HVAC industry, but it has a mylar facing. *I don't know if that would be a good idea for an engine room.

Thanks for your help

Larry B
 
My engines are amidship too. Right under the galley sink, 3-4 ft behind the lower helm. My boat has a foil-lined fiberglass bat type insulation for heat more than sound.

These were applied to the hull as well as the ER ceiling and bulkheads, but the PO removed it from the hull sides.
 
Oh OK, same setup then. *For some reason I was thinking the 34's were in the stern with V drives.*

Yes, probably same insulation I have. *Makes the Gen set a little quieter too, when at anchor. *Some of mine came loose from the ceiling so I removed it all. *Only to put it back up when we realized how much louder the 7.5 kw Onan was with out the insulation. When we changed out the main salon carpet they glued a sound deadening rubber pad to the carpet back as well. *There are*two other 38' Cals in my marina and they have the same engine room insulation. *So it must be standard throughout the series.

Thanks

Larry B
 
While updating my systems, I have been doing a little research on Californian Trawlers and tyring to fill in some of the unknowns.* Since there is very little official documentation regarding our boats and they're long out of production, it is difficult to find facts. To the point:*
I ran across a magazine article the other day that describes the engine room insulation on our boats as lead foil backed fiberglass insulation.* It does have a lead appearance and feel.**I have noticed the metallic backing on mine is beginning to come apart as it ages and flake off.**If this is truly lead, I don't know if this is a health hazard or not.**I had a contractor friend look at it and he says this appears to be similar to the insulation used to wrap HVAC systems, heating and air conditioning, usually in commercial applications.*
Does anyone know the background of this type of insulation, is it lead foil and is it a potential hazard?*
Larry B


-- Edited by Edelweiss on Monday 29th of August 2011 10:42:38 AM
 
My original Californian engine room insulation is beginning to look tired. *Anybody else replaced their's and what was your source? *I don't seem to find the same materials that Marshall used around anywhere. (It had a metalic surface and probably contained lead,
bleh.gif
*) *I have seen some simular looking material, but appears to be a mylar surface.

Try Airtexinteriors.com and their insulation has a sticking back and AL2 surface, good stuff of various thicknesses, for the top their firewall insulation works good also. Yes, this is aircraft quality but works good. wc
 
I think you'll find that if there is lead it's sandwiched inside the material, not on the surface and it will be a solid sheet. Most marine stores around here sell it but it's very spendy.

There is also an insulation that the guys who modify cars use when they are installing those hideous stereos in their trunks. As that has sort of died down now (no pun intended) it might be more cheaply available?
 
What's called "mass loaded vinyl" has replaced lead as a noise barrier for boats under about 70ft. Works as good as lead, weighs the same as lead, is a lot cheaper than lead.

Like Xsbank says, it's usually in layers of foam / vinyl /foam with a silver or white face for engine room insulation.

The automotive product he's describing sounds like Dynamat, its basically a damping material for sheet metal.

There are acoustic carpet underlayments out there that work very well over an engine room, I have it installed in my MKI and it works great.

:socool:
 
xsbank: I think one of the products you're talking about is acoustimat, used to kill road / tire / wind noise on cars, both production and customized.
 
Yes, and I'm very happy with the noise reduction performance and how it feels underfoot. I recommend it to my friends and it's the difference between having a conversation and shouting at cruise speed. I used the 1/2" 1lb version, black side up as recommended.

:socool:


KD, did you use SounDown Carpet underlayment?
 
Which weight/thickness did you go with? This may sound like a stupid question, but is yours a berber carpet or similar with short nap??
 
I used the 1/2" thick 1lb premium version. There are 4 sizes with the premium foam, which I highly recommend. the standard foam is too soft.

the 4 sizes:

1/4" foam 1lb barrier
1/4" foam 2lb barrier
1/2" foam 1lb barrier
1/2" foam 2lb barrier

With noise control, more is usually better, but I think the best "feel" underfoot is the 1/2" 1lb. I stood on a few samples at a boat show a bunch of years ago.

:socool:


Which weight/thickness did you go with? This may sound like a stupid question, but is yours a berber carpet or similar with short nap??
 

Latest posts

Back
Top Bottom