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Discussion Starter · #1 ·
I wanted to get a handle/understanding of the material and places where (the goop) was used to seal the areas that penetrate from the inside to the outside.
There have been discussions mixed in throughout other threads about ( the goop) particularly in our gt's where our wiring comes through the upper box of the fire wall.
I also realized when I removed my gas pedal for some tlc that this same goop was used here as well and I'm sure the same goes for other penetrations in the fire wall ( brake and clutch) among others.

With that being said I have a couple questions as to this topic.

1) What other areas would (the goop) be present as a sealer?

2) What is this foreign material?

3) Is there a similar (preferred material) to replace it with after it had been removed for repairs or restorations.

4) Has anyone made or used a gasket or rubber gasket type material in some of these areas ( like the fuel pedal) as an example to seal them through the firewall?

I have pulled the entire throttle linkage system from pedal to carb for some rehab/tlc and will also be doing the same with the brake/clutch pedals.
When I put them back in I would think certain areas would benefit from a different or better type of gasket or dare I say an innertube material that was custom cut to act as a gasket as opposed to (the goop).

I thank you all in advance for any info and advise as we move forward here.
 

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McMaster Carr sells a similar material. It comes in a roll with anti stick paper in between the wraps like double stick tape does. I will see if I can find it and post the product number. Worst case would be you ask me to send you a small piece. The only place it is used is the engine harness inlet.
 

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McMaster 76385A22 it is called rubber tape. It wads up like Silly Putty. It is also available in thinner widths for less money.
 

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1970 Opel Gt - Purchased July 1972 - Chartreuse - restored - 3000 miles as of 02-16, 2021 -
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Glad that GoldGT remembered what it is and where to get it. I recall purchasing a small box of it back in the mid 90's and it was easy to use and holds up really well. And I only recall using it as described by GoldGT, however as you mentioned there could be other applications where water may penetrate, but I cannot think of any. Additionally I don't think a rubber gasket/bushing would work as well, I mean how are you going to install the new gasket/bushing without cutting it which would defeat the purpose - you would still need the goop to seal around the bushing/gasket. Terry are you putting in a new front wiring harness? Eh.
 

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Other than the wiring harness with rubber sealing tape on it, all of the other areas that needed sealed on my car were sprayed on. Every little screw that penetrated the floor pan for carpet snaps has a spray on black substance that isn't very flexible all these years later. It is very similar to (and may be the exact same product) as some of the sound deadener used on my 69 Z/28. When replicating that material, I used 3M Body Schutz. Nasty stuff. Back in 2012 I had to buy it by the case, and buy a separate applicator gun used with compressed air.
 

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I've used material that comes in a roll about 3/4" in diameter with the anti-stick paper and it was used to affix tempered glass to a metal frame much like windshield gasket material and you would probable need 4 to 6 inches of it, you should have said something a month a go. Maybe a windshield place might have a small piece?
 

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3M Strip Caulk. We used it at the dealer and called it Dum-Dum. It doesn’t harden up quite like the original stuff.
Probably the same type stuff as the rubber tape. It never hardens up at all but it is extremely tough.
 

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3M Strip Caulk. We used it at the dealer and called it Dum-Dum. It doesn’t harden up quite like the original stuff.
Good Lord! Exactly what we called it when I worked at the Buick dealership one summer in the late 1960s. We used quite a bit of it, packing it under the door weather stripping so as to reduce the wind whistle that buyers of the new Buicks constantly complained about.
 

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Discussion Starter · #10 ·
ubber Sealing Tape


Patch and seal roofs, window frames, gutters, and vents with this conformable tape. Both sides have a tacky surface, so tape adheres to itself.
Butyl rubber tape is stretchier and more conformable than EPDM rubber tape.
Polyolefin/rubber blend tape adheres to most surfaces, including vinyl, fiberglass, PVC, wood, and tile. It can even be used on damp nonporous surfaces. This tape will not crack, harden, or shrink, so it’s good for permanent leak repairs. When applying this tape in temperatures below 25° F, a seam primer is advised.
Polyolefin/Rubber Blend Tape
Butyl Rubber Tape
Wd.Lg.,
ft.
Overall
Thick.
Adhesive TypeTemperature
Range, °F
Tensile Strength,
lbs./in. wd.
Adhesion
to Steel
Color Each
4"250.125"Self-Fusing-20° to 180°10Not RatedBlack76385A22$50.11
4"250.035"Self-Fusing-20° to 180°Not RatedNot RatedBlack6165N1138.04
 

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Discussion Starter · #14 ·
Terry are you putting in a new front wiring harness? Eh
No sir, but I will need to reseal that area as I removed it all (and trash canned it) to do some clean up and run a new wire for the electronic ignition
And the rubber gasket idea was for the fuel pedal as it is open where the pedal to linkage arm passes through the fire wall and appears is only sealed around the opening and the (cup) if you will is clearly visible
 

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No sir, but I will need to reseal that area as I removed it all (and trash canned it) to do some clean up and run a new wire for the electronic ignition
And the rubber gasket idea was for the fuel pedal as it is open where the pedal to linkage arm passes through the fire wall and appears is only sealed around the opening and the (cup) if you will is clearly visible
Keep in mind that they didn't have all the silicones that are available today, all you are really doing is creating a barrier to keep the interior sealed in these areas.
 

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This is what I use for general auto body sealing:
TP Tools® Strip Caulk, Black $17.95 - Sale $16.00.
Found the TP Tools website years ago. They have some interesting products.
 

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Discussion Starter · #18 ·
This is what I use for general auto body sealing:
TP Tools® Strip Caulk, Black $17.95 - Sale $16.00.
Found the TP Tools website years ago. They have some interesting products.
I'll be darned Lindsay, I thought when Opelspyder and Michael A Smith said they called it dum dum it was just a saying LOL it actually says dum dum on the darn box LOL
Thank you I am going to get this and look/shop around on there site.
 

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Discussion Starter · #19 ·
I finally was able to place an order (there website was on the fritz)
I also picked this up for the sand blast cabinet as my head is well worn
Gun accessory Composite material Auto part Metal Cylinder
Gun accessory Composite material Auto part Metal Cylinder
 
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