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Engine compartment insulation [message #348598] Fri, 27 September 2019 17:33 Go to next message
6cuda6 is currently offline  6cuda6   Canada
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Registered: June 2019
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Senior Member
Hi folks,

Im looking for suggestions on the best product to insulate my engine compartment for heat and noise BUT i need to do it from inside the engine compartment not inside the coach as i dont want to pull all the great carpet the PO installed.


Rich Mondor, Brockville, ON 77 Hughes 2600
Re: Engine compartment insulation [message #348601 is a reply to message #348598] Fri, 27 September 2019 18:05 Go to previous messageGo to next message
agoogol is currently offline  agoogol   United States
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Registered: August 2019
Location: Centennial, Colorado
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Member
I may be a newbie here, and with my GMC, but you want access from the inside.

Kevin Carter 1977 Kingsley - 403 c.i. Centennial CO
Re: [GMCnet] Engine compartment insulation [message #348604 is a reply to message #348598] Fri, 27 September 2019 18:10 Go to previous messageGo to next message
Ken Henderson is currently offline  Ken Henderson   United States
Messages: 8726
Registered: March 2004
Location: Americus, GA
Karma: 9
Senior Member
You'll probably get a lot of good suggestions, but I'l tell you what I did
20 years ago that's worked quite well ever since: Since I had the engine
compartment empty, including the wheel well liners, anyway, I used "duct
board" to cover every flat surface, horizontal and vertical. Duct board is
a 3/4" thick rigid fiberglass matt covered on one side with an aluminized
mesh. The material is rigid enough that it's used as its name suggests:
To build HVAC ducts -- they just make the ducts from it and duct tape. I
put the covered side down to prevent oil absorption, for waterproofing, and
for thermal protection. The upper, exposed fiberglass matt, I sprayed well
with 3M contact cement augmented here and there with fender washers and
drywall screws. I sealed the exposed edges with aluminum foil duct tape.

I'd feared I'd have trouble with the fiberglass becoming saturated with
water and/or oil, but have had no problem whatsoever -- turns out the
underside of the floor stays pretty clean and dry. If I were doing it
again, I'd cover the exposed side with thin aluminum sheeting. I've
knocked holes in the surface with several things, including pressure washer
spray. But after 20 years, I really have no complaint.

I'd be very reluctant to try to insulate the underside with anything
without gutting the compartment. Just my bias/laziness. :-)

Ken H.
Americus, GA
'76 X-Birchaven w/Cad500/Howell EFI & EBL,
Manny Brakes & 1-Ton, Troy-Bilt APU, etc., etc., etc.
www.gmcwipersetc.com


On Fri, Sep 27, 2019 at 6:34 PM tonka6cuda6--- via Gmclist <
gmclist@list.gmcnet.org> wrote:

> Hi folks,
>
> Im looking for suggestions on the best product to insulate my engine
> compartment for heat and noise BUT i need to do it from inside the engine
> compartment not inside the coach as i dont want to pull all the great
> carpet the PO installed.
> --
> Rich Mondor,
>
> Brockville, ON
>
> 77 Hughes 2600
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
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Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
Re: Engine compartment insulation [message #348608 is a reply to message #348598] Fri, 27 September 2019 19:10 Go to previous messageGo to next message
jhbridges is currently offline  jhbridges   United States
Messages: 8412
Registered: May 2011
Location: Braselton ga
Karma: -74
Senior Member
My 23' had the same stuff, installed by Sirum for the PO. Worked well.

--johnny


Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons. Braselton, Ga. I forgive them all, save those who hurt the dogs. They must answer to me in hell
Re: Engine compartment insulation [message #348615 is a reply to message #348598] Fri, 27 September 2019 20:03 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
Senior Member
What every you do DO NOT USE BUBBLE WRAP.

I use to have small strips of that stuff (about 1/2" x 4") that I would use as a demonstration at the end of the few seminars. I set a match to the stuff and stunk up the room badly. About the only thing that would have been worse would have been using gasoline on the coach. I really caught hell over that one time, and have not been asked to do any seminars since then.

I had a gasoline fueled engine fire in my coach about 10 years ago. The bill to St Farm was over $10,000 to fix it and I did the work cheap. I had insulated mine with a product called micro-foil made by Northern Ohio Foam Products. It looks like bubble wrap but it will not sustain a fire. The stuff held up very well when my engine caught fire. It was easy to install and had good heat rejection. It was rather thin and did not do too much for sound deadening.

http://www.nofp.com/insulation-products/microfoil

I did a group buy of this stuff 12-13 years ago and I got to see them make this stuff. My coach was full of rolls of this stuff when I left. A bunch of us GMCers met for a lunch in Michigan that weekend where we divided it up among about 10 or 12 of us.

They will UPS it to you and it use to be they would sell partial rolls to you if you told them you wanted it for a GMC motorhome. They took a tour of my GMC while I was there. That was years ago so I do not know if they do that any more.

They will send you small samples if you call them. I used up all of my samples in fire demonstrations along side of bubble wrap.



Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: Engine compartment insulation [message #348646 is a reply to message #348615] Sat, 28 September 2019 19:50 Go to previous messageGo to next message
midlf is currently offline  midlf   United States
Messages: 2212
Registered: July 2007
Location: SE Wisc. (Palmyra)
Karma: 1
Senior Member
Here's how id did mine using duct board.

http://www.gmcmhphotos.com/photos/g6094-engine-compartment-insulation.html

I also insulated under the floor section over the exhaust pipes using the same duct board. The areas directly over the exhaust pipes was has additional insulation using sheet metal (pole barn sheet metal).

This would be a very difficult installation with the engine in place.


Steve Southworth
1974 Glacier TZE064V100150 (for workin on)
1975 Transmode TZE365V100394 (parts & spares)
Palmyra WI
Re: Engine compartment insulation [message #348655 is a reply to message #348598] Sun, 29 September 2019 06:54 Go to previous messageGo to next message
6cuda6 is currently offline  6cuda6   Canada
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Registered: June 2019
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Senior Member
Why do i get the feeling this isnt going to be a fun job with the motor in place.

Rich Mondor, Brockville, ON 77 Hughes 2600
Re: Engine compartment insulation [message #348661 is a reply to message #348598] Sun, 29 September 2019 07:55 Go to previous message
jhbridges is currently offline  jhbridges   United States
Messages: 8412
Registered: May 2011
Location: Braselton ga
Karma: -74
Senior Member
Because it's gonna be a P I A, get your arms greasy, and teach you some new vocabulary. But, still less hassle than pulling the motor and transmission out first.

--johnny


Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons. Braselton, Ga. I forgive them all, save those who hurt the dogs. They must answer to me in hell
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