Engine Noise Insulation
Hi Everyone - I'm doing a
quick project tomorrow to try and quite down the sound from my engine. For your
reference, it's the Yanmar 3gm30f. I'm
planning to use the west marine sound insulating material. It's available in
1/2 and 1 inch thicknesses. Previous
review of this lists archives suggest a couple of things.
1. 1/2 inch is the max thickness that can be
installed on the front panel near the crank pulley (i.e., clearance issues).
2. It will take two packages of the material to
cover the surfaces.
3. The material will hold on with the 3m spray
adhesives.
Given my understanding of
these parameters, I was thinking of buying a pack of the 1/2 material and a
pack of the 1 inch material.
Planning to install the 1
inch a material on the rear panel and every where but the front panel by the
crank pulley. At that location install a
small patch of the 1/2 of the half inch material. Any excess 1/2 inch material available, glue
to the 1 inch already installed where clearance exists.
am I on the write track here.
Thanks
Trevor & Jim
I insulated the front cover
this season. Big improvement! I'll do the rear cover next season. A few
comments:
1) Clean the cover
thoroughly before applying the foam.
2) The 1" material that
I purchased at West Marine is backed with a very strong adhesive. I don't see
why you would need any 3M adhesive.
3) Check out my photo of the
installation (Idlewild #545) in the C320
"Owners
Gallery".
I doubt that even 1/2" foam will fit between the cover and the crankshaft
pulley. I used the 1" material and simply cut out a section around the
pulley. I think it would be wasteful to buy a 1/2" kit just for an 8"
circle.
4) After you cut out a piece
and before you install it, tape any exposed foam. That will be easier than
trying to tape it afterwards. Otherwise, heat and oil fumes could cause the
foam to deteriorate over time.
5) For the same reason,
finish up the installation by taping all of the seams.
6) The fasteners are only
suggested for "overhead" surfaces. I attached them with 3M 5200.
7) Leave a 1/2" gap at
the top and side of the cover where it slides behind the wooden pieces that
hold it in place.
Good luck.
Jeff Church
Trevor - Thanks for sending
this along, I must have missed that photo in previous reviews of the
albums.
By my eye's it looks like a
very straightforward job. Seems like you fitted it with two pieces, one covering the sides
and front, a separate one for the top. Judging from your note, the small cut out for
the pulley isn't causing serious degradation of the improvement.
Also, I'm thinking that I’m
going to try and go straight adhesive for the top piece. I've seen a number of posts that suggest the
adhesive is sufficient and you can get away with not
using the fasteners.
Looks like you've done some
nice upgrades, I'm very envious of the Max prop, but can't get that upgrade past
the finance committee.
Cheers
Jim, Jeff,
You'll easily be able to use
1" material everywhere. It fits
fine, works just fine. At the front of
the engine, the bottom half of the engine pulley will be very close if not
touching.
However, this isn't even
remotely an issue. Install it, run the
engine for a few minutes, remove the cover and you'll see just what I
mean. Makes a slight mark on the foil cover and (while it
is not required), you can snip out a small semi-circle of material. It doesn't interfere with any belts, hoses,
wires etc...
I didn't even bother the
first year. The next year I did snip
away ~1/2 inch but it was probably because I was bored, couldn't sail and
needed to feel like I was "doing stuff" on my boat.
The 1/2" stuff won't do
nearly as good a job as the 1" stuff, so I wouldn't waste my money or time
with that...
Just avoid putting any
fasteners near where the engine pulley will go and you'll be just fine.
-Jeff
Jim: Installing the hangers inside the upper
surfaces of the engine compartment was quick and easy for me, doing it with
epoxy per the recommendation. I don't
think the spray adhesive would actually make the job any easier to tell the
truth, what with fumes and the need to keep spray off surrounding
materials. You can purchase a small kit
of
West system epoxy at most
marine stores for about $25. You can purchase
a resin/hardener refill kit for even less, which is all you really need for
this job. Just open and mix the contents
of two pre-measured pouches in a paper cup and glue the fasteners on with this,
with the covers turned up side down so you aren't fighting gravity. The horizontal surfaces aren't that big, so
you are only talking two fasteners per cover anyhow. You do want to thoroughly clean the surfaces
first, but you should do that no matter what you use.
I did the job last spring
using only the 1" insulation, cutting away a bit near
the front pulleys. (I have same engine
as you.) What a difference! I actually took the covers off the boat and
did the job at home. In my experience
when I tackle a job like this on board I tend to cut corners to get it done
quickly. Not so with the covers in my
basement. I didn't mind waiting a few
hours for the epoxy to set up thoroughly.
While some recommend leaving
a gap in the insulation at the edges, everything I've read about noise
insulation suggests that this is a bad idea and that a lot of noise actually emerges
from the edges. I worked hard to make
the fit of the insulation as tight as possible, bringing foam all the way to
the edges whenever there was room.
The covers are significantly
heavier with the 1 inch insulation, but are still quite manageable.
Scott Thompson
I took my engine covers off
the boat last weekend and am trying to install the West Marine engine sound
insulation kits onto the covers in my basement.
I have cut the insulation to a nice fit, but before I start making
things permanent, I have a few questions about the details. I have the Yanmar engine.
1) There is a warning in the instructions to not
install the insulation within 6 inches of the exhaust. Is this a problem with the Yanmar
engine? Do I need to take it back to the
boat to measure? My recollection is that
the exhaust manifold runs underneath (perhaps integral with) the heat
exchanger.
2) I intend to use the method suggested by
someone on the list to find where I have to remove some insulation from the
front cover so that it clears the belts and pulleys. Intention is to mount the cover and then
crank the engine for a few seconds without starting it so that the pulleys
scuff the foil, then cut away around this area.
Question: How much needs to be cut away (depth wise)? Do I mount any insulation at all in these
areas? Should I do this before or after
I glue on the insulation?
3) If I run insulation all the way to all of the
edges of the covers then some of it will not make contact with the covers near
some of the edges because the cover wall thickness is less there. I assume I can just let some of the
insulation hang loose in these areas, as it is stiff and these edges are always
near the bottom of a section. Is there
any problem with doing this, or should I not take the insulation all the way?
Thanks for any help. I hope to finish as much of this tonight as possible,
before going back to the boat.
Scott Thompson
Surprise, #653
Scott,
I am in the middle of this
project right now, and like most things that you only do once, it takes a
little bit of doing and then doing over.
1. I don't know about the engine exhaust
question. I don't think it's a problem.
2. I bought the 1" insulation, knowing that
it wouldn't fit at the lower pulley on the engine. I taped a piece of 1/2" plywood on the
cover next to the pulley, turned the engine over, and the pulley just touches
the 1/2" plywood. So, 1/2"
insulation almost fits.
I found that I could cut the
insulation with a sharp kitchen knife, a serrated one that was about 6"
long and maybe 1" wide. I placed
the 1" insulation in a wood vise to give it support, and just sawed away
near the dense part of the foam. I cut
it so that it was about 3/8" thick.
Then I cut another sheet
fairly close to the foil. Then I used 3M
spray adhesive to stick the two parts together.
They are just under /2" thick now.
I found that I needed to use
thinner (1/2") insulation most of the way along the bottom edge of the
front cover, otherwise it hit the stringers that support the engine and the
cover wouldn't close properly. Unfortunately, I found this out after I stuck
the 1" insulation on the cover. So
I sawed away with the knife again.
Tomorrow I will stick a thin foil part on, and it should work OK.
3. I'm not sure I understand your 3rd
question. I goofed by running the
insulation all the way to the edge along the bottom of the front cover. I should have stopped about 1/4" short
and taped it. So I had to cut it back
with my now pretty dull kitchen knife.
The reason to keep it a little short is next.
4. You didn't ask this part, but a 320 friend
told me the most important thing he did was to run some sort of gasket all
along the edges of both covers.
Otherwise, the sound "leaks" out. I found what I hope is the right stuff. It's made by Taco Marine and is sold by West
Marine (page 490 of the current catalogue).
It has a self-stick backing, and seems to be made of a
black foam latex. I measured for
it today and I will need about 20 feet.
Tomorrow I will buy the 3/8" thick stuff, at about $27 for 25
feet. Taco also makes thicker stuff, up
to 9/16" if you need it. It is not
rated for engine compartments, but is supposed to be good to 150 degrees F. If you want something better, try an auto parts
or car repair shop.
5. The best part is that no one will ever look
inside to see what you've done. It will
work pretty well no matter what. If I
did 2 or 3 of these I might get good at it!
Hope this helps.
Pete Herron
C320 #329
Sailor's Solutions SPM sound
proofing tiles are also a possible choice.
Here is a review: http://www.cncphotoalbum.com/doityourself/soundproofing/
Karl Mielenhausen
2000 C320
From
my archives
The
West Marine Noise Control Barrier Material on Model 216866 had the hangers and
some silver scotch tape (for a better name). It takes 2 kits @ $89.99
each.
Shake
the box and you will hear the parts rattle that is the seam tape and the
hangers. The box did not indicate that this stuff was inside.
You
will need some epoxy or 3M 5200 (That did not come with the kit) to fasten the
hangers on the top parts of the enclosures. Also a pair
of dikes to cut off the extra length of the hangers nails after you push
the material on the box. It sets up quick so you have only 1 minute after
you pull the backing off to put it in the proper place.
Actually
it is fun to work with.
I
put the completed shells back around the motor, turned it over for 10 seconds,
by doing this found that the YANMAK front pulley was making contact with the
material. I then scooped a bit of this out and covered it with the silver
tape.
Elapsed time about 2 hours with Ray Stone being the
chief engineer and GA person.
Cheers,
Dick
Walker
619.435.8986
Just completed sound proofing our
C320 #62 with SPM from SailorSolutions.com The product works well and needs no
mechanical hangers, glue/epoxy, or tape. It's adhesive
backed with a semi-rigid aluminized coating on the engine-side surface. We used
16 tiles 1"X12" square so you will need the 18 piece kit for $150
plus shipping. We ordered online, the product shipped same-day UPS ground, and
we received it 2 days later - WOW.
Instructions say to cut with
scissors or knife. I didn't like the scissors. A utility knife with extendable
blade worked best, gave smooth cuts even on the curves. I think there was only one curved cut and it
was on the front cover. I used a compass
to mark the cut.
On our covers, the 12" squares
worked very well. Many went in without
requiring any cuts, esp. on the aft cover.
With the cutting scraps, we covered the port side fitting around the
coolant overflow bottle and the anti-siphon valve.
We are happy, so far, with SPM.
It took me quite a bit longer, but then I decided to take the covers home with me so that I could spread out while I worked. Actual install time was still a bit longer for me. The hardest part for me was the measuring and cutting, especially the latter. That's probably because I wanted to make sure the insulation came right down to the floor with no gaps anywhere. I've read that even a small gap can drastically reduce the effectiveness of sound insulation. I was very pleased with the significant decrease in noise levels from this mod.
In a separate email, Bert suggests that you can get by with only one kit. I wouldn't advise it. You want to use pieces that are as continuous as possible around corners, etc. to avoid gaps. Also, you really want to do BOTH covers. I'd recommend using a bit of epoxy rather than the 5200 to install the hangers only because it sets up so much faster, letting you get on with the project. The little West system repair packs in the pre-measured pouches are ideal for this.
Scott Thompson
Surprise, 653
The point about closing up the air gaps is critical to good results. A roll of 1/4"x 3/4" self adhesive foam weather stripping works well. Install it all the way around the covers where they mate with the sole and bulkheads. It takes a little time to get it right but is worth the effort.
I found it took most of two insulation kits to do both covers. I used one each of the 1" and 1/2", installing the 1/2" where clearance was an issue, at least for my comfort level.
Both Owner and Captain agree it was worth the trouble.
Now if it will only stop raining in SoCal... Ah well, at least the standing rigging is getting a nice freshwater bath.
Walter
Selkie #887