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What is this stuff? [message #316816]

Sun, 30 April 2017 03:12

Ken Burton

Messages: 10030
Registered: January 2004
Location: Hebron, Indiana

Karma: 10

Senior Member

I have run into this stuff many times on cars but do not know what it is or where to get it. It is a black goo like sealer that is used by car manufacturers on seams and holes. I just ran into it again when working on my clearance lights. It was used to seal the holes where the clearance light wires run through the roof. I saw it also a couple of years ago used to seal a drain hose to the body and fender liner in the left rear fender well.

This stuff never fully hardens and after 40 years it is still flexible. I doubt it is flexible enough to be used in a caulking gun. I currently still have some it smeared on my finger from working on those holes. It does not come off easily. I imagine paint thinner might cut it. I haven't tried it.

Is it the same stuff that is used to seal in windshields?

What is it and where do I buy it?

Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana

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Re: What is this stuff? [message #316817 is a reply to message #316816]

Sun, 30 April 2017 05:53

GMC Jimmy

Messages: 199
Registered: September 2016
Location: Niagara, Ontario

Karma: 2

Senior Member

Hello Ken, I believe the stuff you are looking for is in fact automotive seam sealer.

Here is a link to the product I'm referring to... https://www.napaonline.com/en/p/MMM08367

There other colours available so have a look at the NAPA website for options.

I have used it many times with good results, hope this helps.

Regards,
Mike

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Re: [GMCnet] What is this stuff? [message #316818 is a reply to message #316816]

Sun, 30 April 2017 06:32

USAussie

Messages: 15912
Registered: July 2007
Location: Sydney, Australia

Karma: 6

Senior Member

Ken,

I can't remember what it is called but it comes in strips about 1/8" OD and
12" long. They are layered in a box with each layer separated by a wax
paper. Ken H. told me to use it around the passenger and driver side windows
between the metal and the body.

I bought it at an auto body supply store that sold auto paint, sandpaper,
adhesives, etc.

Regards,
Rob M.
The Pedantic Mechanic
USAussie - Downunder
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426
USA '77 Kingsley - TZE 267V100808

-----Original Message-----
From: Gmclist [mailto:gmclist-bounces@list.gmcnet.org] On Behalf Of Ken
Burton
Sent: Sunday, April 30, 2017 6:13 PM
To: gmclist@list.gmcnet.org
Subject: [GMCnet] What is this stuff?

I have run into this stuff many times on cars but do not know what it is or
where to get it. It is a black goo like sealer that is used by car
manufacturers on seams and holes. I just ran into it again when working on
my clearance lights. It was used to seal the holes where the clearance
light wires run through the roof. I saw it also a couple of years ago used
to seal a drain hose to the body and fender liner in the left rear fender
well.

This stuff never fully hardens and after 40 years it is still flexible. I
doubt it is flexible enough to be used in a caulking gun. I currently
still have some it smeared on my finger from working on those holes. It
does not come off easily. I imagine paint thinner might cut it. I haven't
tried it.

Is it the same stuff that is used to seal in windshields?

What is it and where do I buy it?
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana

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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

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Re: [GMCnet] What is this stuff? [message #316819 is a reply to message #316818]

Sun, 30 April 2017 06:41

GMC.LES

Messages: 505
Registered: April 2014

Karma: -2

Senior Member

Rob's correct, and the stuff is called butyl mastic, which never cures and remains sticky and workable for many years. It comes in strips or rolls, with each layer separated by paper.

Residue is easily cleaned up with mineral spirits or similar solvents.

http://www.devansealants.com/specialty-sealants-and-adhesives/butyl-mastic-tape/

Les Burt
Montreal

> On Apr 30, 2017, at 7:32 AM, Rob Mueller wrote:
>
> Ken,
>
> I can't remember what it is called but it comes in strips about 1/8" OD and
> 12" long. They are layered in a box with each layer separated by a wax
> paper. Ken H. told me to use it around the passenger and driver side windows
> between the metal and the body.
>
> I bought it at an auto body supply store that sold auto paint, sandpaper,
> adhesives, etc.
>
> Regards,
> Rob M.
> The Pedantic Mechanic
> USAussie - Downunder
> AUS '75 Avion - The Blue Streak TZE365V100428
> USA '75 Avion - Double Trouble TZE365V100426
> USA '77 Kingsley - TZE 267V100808
>
> -----Original Message-----
> From: Gmclist [mailto:gmclist-bounces@list.gmcnet.org] On Behalf Of Ken
> Burton
> Sent: Sunday, April 30, 2017 6:13 PM
> To: gmclist@list.gmcnet.org
> Subject: [GMCnet] What is this stuff?
>
> I have run into this stuff many times on cars but do not know what it is or
> where to get it. It is a black goo like sealer that is used by car
> manufacturers on seams and holes. I just ran into it again when working on
> my clearance lights. It was used to seal the holes where the clearance
> light wires run through the roof. I saw it also a couple of years ago used
> to seal a drain hose to the body and fender liner in the left rear fender
> well.
>
> This stuff never fully hardens and after 40 years it is still flexible. I
> doubt it is flexible enough to be used in a caulking gun. I currently
> still have some it smeared on my finger from working on those holes. It
> does not come off easily. I imagine paint thinner might cut it. I haven't
> tried it.
>
> Is it the same stuff that is used to seal in windshields?
>
> What is it and where do I buy it?
> --
> Ken Burton - N9KB
> 76 Palm Beach
> Hebron, Indiana
>
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
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Re: What is this stuff? [message #316823 is a reply to message #316816]

Sun, 30 April 2017 07:46

SpookyEng

Messages: 208
Registered: June 2016
Location: Navarre, FL

Karma: -5

Senior Member

Good question Ken! Apparently it is available at Home Depot http://www.homedepot.com/p/Fabral-1-4-in-x-40-ft-Butyl-Rubber-Sealant-Tape-40BT/207149821

JD Lisenby- USAF Ret 1978 Royale-455 MacDash, Manny Tranny, FI-tech, 3.70 etc etc Navarre, FL

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Re: [GMCnet] What is this stuff? [message #316824 is a reply to message #316817]

Sun, 30 April 2017 07:50

Keith Weeks

Messages: 11
Registered: May 2012

Karma: 0

Junior Member

Keith Weeks | 1402 So. Cage Blvd., Unit 273, Pharr, Texas 78577
612.978.7243

> On Apr 30, 2017, at 5:53 AM, Mike wrote:
>
> Hello Ken, I believe the stuff you are looking for is in fact automotive seam sealer.
>
> Here is a link to the product I'm referring to... https://www.napaonline.com/en/p/MMM08367
>
> There other colours available so have a look at the NAPA website for options.
>
> I have used it many times with good results, hope this helps.
>
> Regards,
> Mike
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org

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Re: [GMCnet] What is this stuff? [message #316827 is a reply to message #316824]

Sun, 30 April 2017 09:11

Hal StClair

Messages: 971
Registered: March 2013
Location: Rio Rancho NM

Karma: -12

Senior Member

I know the stuff you're refering to Ken, you see it in numerous places. It may be butyl but certainly has a different consistency than the butyl on the rolls I've used. It seems to have more of a tar consistency. No help on the product name though.
Hal

"I enjoy talking to you. Your mind appeals to me. It resembles my own mind, except you happen to be insane." 1977 Royale 101348, 1977 Royale 101586, Diesel powered, 1974 Eagle Bus 45',w/slideout, Rio Rancho, NM

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Re: What is this stuff? [message #316828 is a reply to message #316823]

Sun, 30 April 2017 09:14

Ken Burton

Messages: 10030
Registered: January 2004
Location: Hebron, Indiana

Karma: 10

Senior Member

Thanks for all of the answers. Is this the same stuff that Gene Dotson was supplying by the roll for sealing CR Lawrence windows?

I have a small remainder of a roll that came from my windshield installation buddy. I tore off little strips about 2.5 inches long and formed it to seal the holes under the clearance lights. I have only done 4 of them so far.

The 5th one is going to be a bear. Both screws are rusted and it is up against my awning. I have it soaking in Kroil right now. I found that heating the screws for 4 or 5 minutes with a soldering iron and then shock cooling the screws with Kroil worked well for getting out the rusted screws. Before I did this I could not get them loose with a set of needle nose vice grips. After heating and oiling with Kroil a few times they turned easily with a pair of pliers. Let's hope hope I have the same luck with the final one on the rear.

Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana

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Re: [GMCnet] What is this stuff? [message #316838 is a reply to message #316828]

Sun, 30 April 2017 12:59

sgltrac

Messages: 2797
Registered: April 2011

Karma: 1

Senior Member

I believe the butyl mentioned above in the this thread is what you are
referring to Ken. Back in the day windshields and back glass auto glass was
installed with this material. It can be purchased in coiled ropes of
various diameters ( 1/4",5/16",3/8" being the most common). It is also
available in rolled strips typically 1/8" thick and varying width which
would be used for rv windows and other protrusions like furnaces and vents.
It is available in block form at home depot which is super handy for
packing bigger holes like the ones in the rear floor at the joint between
the rear body and corner smc panels. I have had two gmcs and both if them
had gaps in this area which created a super convenient pathway for mice.

Sully
77 eleganza 2
Seattle
On Sun, Apr 30, 2017 at 7:15 AM Ken Burton wrote:

> Thanks for all of the answers. Is this the same stuff that Gene Dotson
> was supplying by the roll for sealing CR Lawrence windows?
>
> I have a small remainder of a roll that came from my windshield
> installation buddy. I tore off little strips about 2.5 inches long and
> formed it to
> seal the holes under the clearance lights. I have only done 4 of them so
> far.
>
> The 5th one is going to be a bear. Both screws are rusted and it is up
> against my awning. I have it soaking in Kroil right now. I found that
> heating the screws for 4 or 5 minutes with a soldering iron and then shock
> cooling the screws with Kroil worked well for getting out the rusted
> screws. Before I did this I could not get them loose with a set of needle
> nose vice grips. After heating and oiling with Kroil a few times they
> turned easily with a pair of pliers. Let's hope hope I have the same luck
> with the final one on the rear.
> --
> Ken Burton - N9KB
> 76 Palm Beach
> Hebron, Indiana
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
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Sully 77 Royale basket case. Future motorhome land speed record holder(bucket list) Seattle, Wa.

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Re: What is this stuff? [message #316851 is a reply to message #316816]

Sun, 30 April 2017 17:53

jhbridges

Messages: 8412
Registered: May 2011
Location: Braselton ga

Karma: -74

Senior Member

Ken, it's also supplied with coax grounding kits and some fittings. Andrew Corporation would know what it is, and probably a source.

--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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Re: What is this stuff? [message #316858 is a reply to message #316851]

Sun, 30 April 2017 19:40

Ken Burton

Messages: 10030
Registered: January 2004
Location: Hebron, Indiana

Karma: 10

Senior Member

Thanks. I have some of that stuff around that is used for outdoor coax sealant.

Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana

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