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Topic: Generator Compartment Insulation (Read 1324 times) previous topic - next topic

Generator Compartment Insulation

I have a small pc. of what I would consider insulation or sound deadener that has turned loose in the generator compartment.  Does anyone know what that material might be?  It appears to be a piece of rubber with foam on both sides. 
When restoring muscle cars we use a product called dynamat for insulation purposes as well as sound deadener.  Do you feel this would be adaquate? and also, am I correct in my assumption its primary purpose is sound deadening?
Jerry
Jerry & Nanci
1999 U270 34'WTFI
2011 Malibu
A smart man knows what to say, a wise man knows when to say it.

Re: Generator Compartment Insulation

Reply #1
Jerry,
The original material that I've seen used in engine and generator compartments is a multilayer composition of a foam with an intermediate isolating layer of vinyl (used to be lead in the old days).  Typically it would be foil faced with the foil facing the engine.  I believe the foil is to reflect radiant engine heat to help slow down the heat induced aging of the foam.  I can't speak to the usage of Dynamat but I have spoken with an acoustic consultant at my previous work (on  locomotives) and he said the material I mentioned above was the most effective for engine noise - it's also quite expensive.
Here's a previous thread on the subject with one member (John Cooper) posting his shopping information: engine compartment insulation revisited
John Fitzgerald
1991 U300 (SAI) Side Aisle Island Bed 40'
Detroit 6V92 with Allison Retarder
Meridian (Boise), Idaho

Re: Generator Compartment Insulation

Reply #2
Hi John,
Thanks for the info.  The current lining reminds me of the material used for headliners in automobiles.  I cant understand trying to attach anything with a foam base and expecting it to stay an  extended period.  That foam is going to deteriorate and come loose.  I wasnt able to open the spreadsheet, possibly because I dont have a full version of excel on this machine I will try another later.
Thanks again.
Jerry
Jerry & Nanci
1999 U270 34'WTFI
2011 Malibu
A smart man knows what to say, a wise man knows when to say it.

Re: Generator Compartment Insulation

Reply #3
Jerry,
AAP Inc makes a product called whisper mat that they engineered to insulate quiet boxes for custom coaches.
I used it in the engine and generator compartments. It was easy up work with, looked great and did a good job with heat on the bed and engine noise.
Call and ask them to send a small sample.
804-633-9454.
JD
John Duld
1995 U320C SE 40'

Re: Generator Compartment Insulation

Reply #4
I wasnt able to open the spreadsheet, possibly because I dont have a full version of excel on this machine I will try another later.
If you're still interested here it is in .PDF
Hi John,
I cant understand trying to attach anything with a foam base and expecting it to stay an  extended period.  That foam is going to deteriorate and come loose.
While some of the foams come with a self adhesive backing, most applications require screws with large flat washers to hold it in place.
John Fitzgerald
1991 U300 (SAI) Side Aisle Island Bed 40'
Detroit 6V92 with Allison Retarder
Meridian (Boise), Idaho

Re: Generator Compartment Insulation

Reply #5
John,
Thanks for sending in PDF very good info.
JD I will be calling for a sample.
Thanks,
Jerry
Jerry & Nanci
1999 U270 34'WTFI
2011 Malibu
A smart man knows what to say, a wise man knows when to say it.

Re: Generator Compartment Insulation

Reply #6
Jerry,
If you can't get a sample let me know and I will send you a piece.
They can include some info on the product.
John Duld
1995 U320C SE 40'

Re: Generator Compartment Insulation

Reply #7
JD,
Thanks, if they wont send a sample I will get back with you.
Jerry
Jerry & Nanci
1999 U270 34'WTFI
2011 Malibu
A smart man knows what to say, a wise man knows when to say it.

Re: Generator Compartment Insulation

Reply #8
Jerry,

The foam I used was adhesive backed and stuck real well after cleaning off the glue from the original.  I used stainless steel square drive fasteners with homemade aluminum washers to support the foam on the top of the generator box.  I made the washers using a sheet of aluminum that I drilled with a one inch hole saw on my drill press.  If you make your own washers make sure you clamp the aluminum sheet down well as it will spin.  I used a 2x6 chunk of wood for a backer.  BTW, the new insulation really quieted the noise.

John
John Cooper
'91 GV 36'
Oshkosh chassis
Cat 3208T 300HP

Re: Generator Compartment Insulation

Reply #9
John,
Do you remember the brand of insulation and where you got it?
Jerry
Jerry & Nanci
1999 U270 34'WTFI
2011 Malibu
A smart man knows what to say, a wise man knows when to say it.

Re: Generator Compartment Insulation

Reply #10
JD,
Thanks for the AAP number.  Nice people.  The sample is on the way.
Jerry
Jerry & Nanci
1999 U270 34'WTFI
2011 Malibu
A smart man knows what to say, a wise man knows when to say it.

Re: Generator Compartment Insulation

Reply #11
Our generator had noise insulating foam (foil on generator side) underneath the engine and generator.  It was about 1/2" thick and looked to be some sort of rubber or plastic flexible foam.  When we had a diesel leak in the return line from the generator, this insulation got soaked with fuel.  I think it delayed detecting the leak and also created a potential fire hazard.  When I had the fuel leak fixed I removed the foam so I can see any new leaks sooner.

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George Hatfield

  Never ever use World Line Motors of Nacogdoches for service!

Re: Generator Compartment Insulation

Reply #12
Reading your post on the material used and I have used a similar material for Caterpillar Tractors to insulate the cab floors 3/8" thk. for use inside of mines. Check your local Cat Dealer and yes it is expensive but works great. It too is lead lined. They also make a thicker material 1" thk. but it is not for use next to engines as it is perforated vinyl for the walls of the cabs. I used this in 1972 building a car, long before Dynamat came along, and when finished you could almost hear a pin drop.

John
John Smith
1994 U280 36' John, Pauline, & Marley Cat
2010 Ford Fusion

Re: Generator Compartment Insulation

Reply #13
JD,
Recieved the sample today.  It looks nice, but I haven't had time to read the paerwork included.
I was surprised to get the sample so quick.
Jerry
Jerry & Nanci
1999 U270 34'WTFI
2011 Malibu
A smart man knows what to say, a wise man knows when to say it.