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Replacing material under floor [message #290695] Sat, 21 November 2015 22:36 Go to next message
The Dr is currently offline  The Dr   United States
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Registered: July 2014
Location: Toledo, OR
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While performing what I think was described as the 2 hour job of replacing the body pads, which I believe took me four days Embarassed I discovered that my original trip from Georgia to Oregon was nearly a disaster. One of the joints after the mufflers leaked badly and took out the insulation, some of the metal foil cover, a good chunk of the full length body pad and some of the wood on the frame rail.

First the exhaust has been fixed and should not be a problem for now. After removing the charcoal, any suggestions or links for material to replace the insulation and the metal foil cover?

I am thinking about putting in shields around the joints in the exhaust just in case. I also seem to remember heat shields for the fuel tanks that Applied probably has. Any other things I should be considering?

This brake job has gotten to be a lot bigger than expected. Big surprise, no? Confused

Thanks.


Mike Sauer Toledo, OR 1975 26' Avion 1-ton front end, SullyBilt AirBag System, 3.21 tranny
Re: Replacing material under floor [message #290698 is a reply to message #290695] Sun, 22 November 2015 00:03 Go to previous messageGo to next message
Adrien G. is currently offline  Adrien G.   United States
Messages: 474
Registered: May 2008
Location: Burns Flat, OK 73624
Karma: 1
Senior Member
The Dr wrote on Sat, 21 November 2015 22:36
While performing what I think was described as the 2 hour job of replacing the body pads, which I believe took me four days Embarassed I discovered that my original trip from Georgia to Oregon was nearly a disaster. One of the joints after the mufflers leaked badly and took out the insulation, some of the metal foil cover, a good chunk of the full length body pad and some of the wood on the frame rail.

First the exhaust has been fixed and should not be a problem for now. After removing the charcoal, any suggestions or links for material to replace the insulation and the metal foil cover?

I am thinking about putting in shields around the joints in the exhaust just in case. I also seem to remember heat shields for the fuel tanks that Applied probably has. Any other things I should be considering?

This brake job has gotten to be a lot bigger than expected. Big surprise, no? Confused

Thanks.


Mike, A similar thing happened on my coach, a bad muffler over heated expanding and warping the foam and alum cover.
The alum cover is about .015 thick (galvanized could be used), the foam is 3/4 inch thick (foam board from HD or Lowes) will do. The alum sheet can be replaced in
2 pieces and pop rivet the overlap.
I moved the muffler to the rear, and for exhaust pipe heat shield I used 5 inch exhaust pipe and elbows sliced in half with a few "U" shape stand off
welded (pop rivets can work also) to the shields, and used hose clamps to hold the shields to the exhaust pipe.

If your coach doesn't have shields at the gas and black tanks, consider getting them in, fuel doesn't need more heat then what it will normally get.

FWIW hope this helps.




Adrien & Jenny Genesoto 75 Glenbrook (26-3) Mods LS3.70 FD / Reaction Sys / 80mm Front&Intermidiate / Hydroboost / 16" Tires / Frame Rebuild / Interior Rebuild Yuba City,Ca. Text 530-nine-3-three-3-nine-nine-6
Re: [GMCnet] Replacing material under floor [message #290714 is a reply to message #290695] Sun, 22 November 2015 08:26 Go to previous messageGo to next message
bdub is currently offline  bdub   United States
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Registered: February 2004
Location: Central Texas
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Senior Member

Kelvin used cookie sheets.
http://www.gmcmhphotos.com/photos/g4989-muffler-heat-shields.html


bdub
Central Texas | Late 1976 Palm Beach
www.bdub.net/GMCLinks.html
https://www.facebook.com/groups/classicgmcmotorhomes/
https://www.facebook.com/groups/gmcmm/



-----Original Message-----
From: Gmclist On Behalf Of Mike Sauer
Sent: Saturday, November 21, 2015 10:37 PM

While performing what I think was described as the 2 hour job of replacing the body pads, which I believe took me four days :blush:
I discovered that
my original trip from Georgia to Oregon was nearly a disaster. One of the joints after the mufflers leaked badly and took out the
insulation, some of
the metal foil cover, a good chunk of the full length body pad and some of the wood on the frame rail.

First the exhaust has been fixed and should not be a problem for now. After removing the charcoal, any suggestions or links for
material to replace
the insulation and the metal foil cover?

I am thinking about putting in shields around the joints in the exhaust just in case. I also seem to remember heat shields for the
fuel tanks that
Applied probably has. Any other things I should be considering?



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bdub
'76 Palm Beach/Central Texas
www.bdub.net
www.gmcmhphotos.com
www.gmcmotorhomemarketplace.com
www.gmcmhregistry.com
www.facebook.com/groups/classicgmcmotorhomes
www.facebook.com/groups/gmcmm
Re: [GMCnet] Replacing material under floor [message #290715 is a reply to message #290714] Sun, 22 November 2015 08:41 Go to previous messageGo to next message
midlf is currently offline  midlf   United States
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Registered: July 2007
Location: SE Wisc. (Palmyra)
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Senior Member
Or you can try Applied GMC for these:

http://www.appliedgmc.com/prod.itml/icOid/760

They look pricey but what is your time worth?


Steve Southworth
1974 Glacier TZE064V100150 (for workin on)
1975 Transmode TZE365V100394 (parts & spares)
Palmyra WI
Re: Replacing material under floor [message #290757 is a reply to message #290698] Mon, 23 November 2015 07:40 Go to previous messageGo to next message
thesmith is currently offline  thesmith   United States
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Doesnt foam board burn really well? Is there an alternative that wouldn't make things worse if the Aluminium layer fails.
Though I suppose the AL would severely restrict fire spread even if it fails locally.....

In the good (bad) old days they would use asbestos, but is there a modern equivalent that is less pricy than a Space Shuttle Tile?



Pete






Mike, A similar thing happened on my coach, a bad muffler over heated expanding and warping the foam and alum cover.
The alum cover is about .015 thick (galvanized could be used), the foam is 3/4 inch thick (foam board from HD or Lowes) will do. The alum sheet can be replaced in
2 pieces and pop rivet the overlap.
I moved the muffler to the rear, and for exhaust pipe heat shield I used 5 inch exhaust pipe and elbows sliced in half with a few "U" shape stand off
welded (pop rivets can work also) to the shields, and used hose clamps to hold the shields to the exhaust pipe.

If your coach doesn't have shields at the gas and black tanks, consider getting them in, fuel doesn't need more heat then what it will normally get.

FWIW hope this helps.


[/quote]


Cary, NC 1978 Center Kitchen Royale.
Re: Replacing material under floor [message #290770 is a reply to message #290757] Mon, 23 November 2015 10:25 Go to previous messageGo to next message
Adrien G. is currently offline  Adrien G.   United States
Messages: 474
Registered: May 2008
Location: Burns Flat, OK 73624
Karma: 1
Senior Member
thesmith wrote on Mon, 23 November 2015 07:40
Doesnt foam board burn really well? Is there an alternative that wouldn't make things worse if the Aluminium layer fails.
Though I suppose the AL would severely restrict fire spread even if it fails locally.....

In the good (bad) old days they would use asbestos, but is there a modern equivalent that is less pricy than a Space Shuttle Tile?



Pete






Mike, A similar thing happened on my coach, a bad muffler over heated expanding and warping the foam and alum cover.
The alum cover is about .015 thick (galvanized could be used), the foam is 3/4 inch thick (foam board from HD or Lowes) will do. The alum sheet can be replaced in
2 pieces and pop rivet the overlap.
I moved the muffler to the rear, and for exhaust pipe heat shield I used 5 inch exhaust pipe and elbows sliced in half with a few "U" shape stand off
welded (pop rivets can work also) to the shields, and used hose clamps to hold the shields to the exhaust pipe.

If your coach doesn't have shields at the gas and black tanks, consider getting them in, fuel doesn't need more heat then what it will normally get.

FWIW hope this helps.



[/quote]


Mike,
Yes foam is flammable, so is most everything else with enough heat. There may be some flame retardant foam available, but never searched for it.
If your mufflers are up front, either get muffler heat shields to put on them or cocky trays, or an oil drip pan to fasten under the floor for
the heat shields or both if that makes you feel safer.
Minimize the radiated heat generated during long drives from parts that don't need the heat, floors/tanks hoses and ...?.
Sometimes at fuel stops, look under the coach for leaks of water/fuel/oil/brake fluid and ....?.






Adrien & Jenny Genesoto 75 Glenbrook (26-3) Mods LS3.70 FD / Reaction Sys / 80mm Front&Intermidiate / Hydroboost / 16" Tires / Frame Rebuild / Interior Rebuild Yuba City,Ca. Text 530-nine-3-three-3-nine-nine-6
Re: [GMCnet] Replacing material under floor [message #290798 is a reply to message #290770] Mon, 23 November 2015 18:11 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
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Registered: July 2007
Location: Sydney, Australia
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Senior Member
Adrien,

"We" are aware that the spray in foam insulation in the walls and ceiling of a GMC is highly flammable.

Are you saying that the foam in the aluminum / foam sandwich under the floor is flammable as well?

Regards,
Rob M.
The Pedantic Mechanic
Sydney, Australia


-----Original Message-----
From: Adrien Genesoto

Mike,
Yes foam is flammable, so is most everything else with enough heat. There may be some flame retardant foam available, but never
searched for it.
If your mufflers are up front, either get muffler heat shields to put on them or cocky trays, or an oil drip pan to fasten under the
floor for
the heat shields or both if that makes you feel safer.
Minimize the radiated heat generated during long drives from parts that don't need the heat, floors/tanks hoses and ...?.
Sometimes at fuel stops, look under the coach for leaks of water/fuel/oil/brake fluid and ....?.

Adrien


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Regards, Rob M. (USAussie) The Pedantic Mechanic Sydney, Australia '75 Avion - AUS - The Blue Streak TZE365V100428 '75 Avion - USA - Double Trouble TZE365V100426
Re: [GMCnet] Replacing material under floor [message #290809 is a reply to message #290798] Mon, 23 November 2015 21:13 Go to previous messageGo to next message
Adrien G. is currently offline  Adrien G.   United States
Messages: 474
Registered: May 2008
Location: Burns Flat, OK 73624
Karma: 1
Senior Member
USAussie wrote on Mon, 23 November 2015 18:11
Adrien,

"We" are aware that the spray in foam insulation in the walls and ceiling of a GMC is highly flammable.

Are you saying that the foam in the aluminum / foam sandwich under the floor is flammable as well?

Regards,
Rob M.
The Pedantic Mechanic
Sydney, Australia


-----Original Message-----
From: Adrien Genesoto



Mike,
Yes foam is flammable, so is most everything else with enough heat. There may be some flame retardant foam available, but never
searched for it.
If your mufflers are up front, either get muffler heat shields to put on them or cocky trays, or an oil drip pan to fasten under the
floor for
the heat shields or both if that makes you feel safer.
Minimize the radiated heat generated during long drives from parts that don't need the heat, floors/tanks hoses and ...?.
Sometimes at fuel stops, look under the coach for leaks of water/fuel/oil/brake fluid and ....?.

Adrien


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Rob,

The small unscientific test that I did with foil covered foam showed me that when flame is removed it will not sustain the continuation of the flame.
If flame is continued with another source of combustible material, the foam board will burn at a slow rate until the combustible material has burned up,
or the distance between the 2 items is great enough for the foam to not sustain burning.
So, in a way the foil covered foam boards can be considered flame resistant. If this is what's considered flame resistant.
But with all the other interior combustible materials that a coach has (wood, upholstery, LP if tank is open and hose/tube failure, and...?),
makes me think that in the end the foil foam board wont help much. It will burn up also.

I insulated my coach with foiled foam board as much as possible, and canned foam for glue and gap fill. Not because of the flame, but availability
and ease of the job.


Just my opinion.




Adrien & Jenny Genesoto 75 Glenbrook (26-3) Mods LS3.70 FD / Reaction Sys / 80mm Front&Intermidiate / Hydroboost / 16" Tires / Frame Rebuild / Interior Rebuild Yuba City,Ca. Text 530-nine-3-three-3-nine-nine-6
Re: [GMCnet] Replacing material under floor [message #290820 is a reply to message #290809] Mon, 23 November 2015 23:28 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
Karma: 6
Senior Member
Adrien,

You may or may not be aware of this document: http://www.gmceast.com/technical/Mueller_GMCer-Fire-Guide.pdf

I continually gather information to update this document as "WE" learn things. Back on September 1st I started a thread:

Subject: GMC Fire Investigation - Bob Dunahugh:

http://gmc.mybirdfeeder.net/GMCforum/index.php?t=msg&th=35076&goto=286283&rid=1271#msg_286283

Unfortunately there weren't many responses and while the cause of Bob's fire may have been determined I, for one, have no idea what
caused it. It's quite possible I missed it but I monitor the GMCnet pretty closely and I would hope I'd pickup the cause of his
fire.

While the rambling nature of discussions on this forum is part of its charm and makes it interesting that does create a problem when
trying to do research. Important information gets buried in messages like this one. You've provided some good information regarding
testing you did on foil covered foam but it wasn't the material GMC used in our coaches.

BTW if you take a chunk of the spray in foam that GMC used and put it on the ground and light it, it will go out. However, installed
it burns like CRAZY!

Regards,
Rob M.
The Pedantic Mechanic


-----Original Message-----
From: Adrien Genesoto

Rob,

The small unscientific test that I did with foil covered foam showed me that when flame is removed it will not sustain the
continuation of the flame.
If flame is continued with another source of combustible material, the foam board will burn at a slow rate until the combustible
material has burned up, or the distance between the 2 items is great enough for the foam to not sustain burning.
So, in a way the foil covered foam boards can be considered flame resistant. If this is what's considered flame resistant.
But with all the other interior combustible materials that a coach has (wood, upholstery, LP if tank is open and hose/tube failure,
and...?), makes me think that in the end the foil foam board wont help much. It will burn up also.

I insulated my coach with foiled foam board as much as possible, and canned foam for glue and gap fill. Not because of the flame,
but availability and ease of the job.

Just my opinion.

Adrien


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Regards, Rob M. (USAussie) The Pedantic Mechanic Sydney, Australia '75 Avion - AUS - The Blue Streak TZE365V100428 '75 Avion - USA - Double Trouble TZE365V100426
Re: [GMCnet] Replacing material under floor [message #290832 is a reply to message #290820] Tue, 24 November 2015 08:16 Go to previous message
The Dr is currently offline  The Dr   United States
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Registered: July 2014
Location: Toledo, OR
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Thanks to everyone for all the ideas.

Mike Sauer Toledo, OR 1975 26' Avion 1-ton front end, SullyBilt AirBag System, 3.21 tranny
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