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I'm looking for information regarding two different kinds of goop. First I'd like to know what GM used to fill holes and gaps in the body. The 50+ year old stuff the looks like gobs of tar that has hardened to a brittle glob that flakes off. Next I'm looking for a sealer to use between the firewall and the AC evaporator case. I want to use non adhesive silicone so I don't destroy the plastic evaporator case if I ever have to remove it. That stuff they use on boats is stronger than the firewall steel and is almost impossible to remove once it sticks.
It's called "Seam Sealer" - Google search it. Decide if you want white, black, paint-able, brush-able, caulk tube. Personally I'd go with the 3M brand.
For the AC box I have used "Strip caulk" and it worked quite well. Others may use something else.
I've used the 3M strip caulk on the AC box before. It works well. It comes in a roll of adhesive foam strip with a pull away backing. It's not so adhesive that it permanently sticks to the box and would damage it during removal.
It is not. It is black tar like substance. I guess it might be seam sealer but it is used to fill some quite large gaps. For example it provides a seal where the aluminum tube that comes out of the plastic evaporator case and goes to the expansion valve.
I've used the 3M strip caulk on the AC box before. It works well. It comes in a roll of adhesive foam strip with a pull away backing. It's not so adhesive that it permanently sticks to the box and would damage it during removal.
I like that Idea. I think that is probably the best way to go. It sounds like it's a lot less messy too. Thanks for the suggestion.
Go with the 3M strip calk as already suggested above. Relatively low cost, easy to use, no real mess and you'll be able to remove the box easily in the future should the need arise. You can use the same product to seal the two halves of the evaporator case together as well.....there's a channel molded into the box halves where they meet (as well as where the box halves contact the firewall).....that's where the factory placed the calk. Might need to use at least two rows of the strip calk for sealing to the firewall.
As far as the "aluminum tubes" you mention (one large one up top that wraps around to the POA valve and a smaller tube down below)....the factory used a different style/type of material there. Some call it "evaporator bulb insulation". Should be available locally. I have a large roll of the stuff....don't know if it's sold in smaller sections or not. It's a flat ribbon product about 1.5" wide and fairly thin. Has the "calk" part but also seems to have some other material mixed in w/the calk (maybe to add "insulation"???...who knows) that gives it a different appearance VS. strip calk.
The 3M strip calk product is PN 08578 (black). Not sure what someone said about "foam" above....the strip calk comes in a box of many strips (about 12" long) that you just pull away from the wax paper dividers inside the box. One box is PLENTY.....you'll have A LOT left over.
It is black tar like substance... it provides a seal where the aluminum tube that comes out of the plastic evaporator case and goes to the expansion valve.
The factory sealed both gaps where refrigerant tubes enter the case with formed pieces of polyethylene foam, put in when assembling the evaporator case.
A previous owner may have improvised a seal on your car.
The factory sealed both gaps where refrigerant tubes enter the case with formed pieces of polyethylene foam, put in when assembling the evaporator case.
A previous owner may have improvised a seal on your car.
There is a formed foam piece on the upper pipes (the larger alum pipe and a smaller alum oil line - available from some repro places I think)...but the factory stuffed/wrapped the lines with the "evap bulb insulation" material after the case was assembled.
See PICS below for detail. First pic is a un-messed-with original '70 AC evap case.
It is not. It is black tar like substance. I guess it might be seam sealer but it is used to fill some quite large gaps. For example it provides a seal where the aluminum tube that comes out of the plastic evaporator case and goes to the expansion valve.
Ok, yeah that's the strip adhesive also discussed here. Seam sealer is for seams. You're talking about assemblies, not seams.
There is a formed foam piece on the upper pipes (the larger alum pipe and a smaller alum oil line - available from some repro places I think)...but the factory stuffed/wrapped the lines with the "evap bulb insulation" material after the case was assembled.
See PICS below for detail. First pic is a un-messed-with original '70 AC evap case.
Where does one et this stuff? Do you have the name of the product, the manufacturer, the part number and a source for this stuff?
Where does one et this stuff? Do you have the name of the product, the manufacturer, the part number and a source for this stuff?
You can find this stuff almost anywhere & by many various names - it's basically "refrigerant tape". Your local automotive parts/supply store might well have some in stock.
I bought the mombo-jombo roll when I restored my '71 CS Convertible A/C (along w/ various other components from old air) mostly because I had/have many other uses for this fine gooey gunk. Be diligent, find vendors who offer free shipping if you buy on-line and note the length of the roll you're buying. Good Luck!
Where does one et this stuff? Do you have the name of the product, the manufacturer, the part number and a source for this stuff?
Greetings - Here's what you're looking for:
Cork/asphalt AC insulation tape, NapaTemp Part #: TEM 209491. Or, if you're not a fan of NAPA, Murray calls it Climate Control Insulation Tape: 59010.
Their respective web pages show those are both 30 foot rolls!
Sell off the unused remainder to others on here doing the same repair
