underlay / sound insulation options questions

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OPN PONY

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Tried a search thinking this had already been discussed but no luck.

Background:

What was supposed to be a freshen up paint job has turned to a more major project. My body and paint guy wanted the rear interior removed in order to cover paint right inside the door jamb. I peeled up the factory carpet underlay sound deadner and found a weak spot in a weird area. A mouse (or something bigger) built a nest under the driver's side rear seat and apparently either lived there a long time or drank heavily leaving behind a lot liquid corrosion because compared to the rest of the floor it is weak. Its only a small area and the rest of the floor just has surface rust but its time to sandblast, repair and repaint the floors.

Question: The factory underlay broke apart and a lot can't be reused. It seemed to hold moisture against the floor creating surface rust anyway. What have you guys used to replace the sound deadner insulation and are there any options that will avoid moisture probs but look sort of original?

I searched Don's website and it looks like there is an OEM style kit but out of stock for a 71-73 convertible. Has anyone used this style of replacement and if so how did it work? Does it seem to hold moisture?

 

OLE PONY

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I went with the original style underlayment. My floor was solid because back in 1974 I removed the interior and rustproofed the floor. When I removed the carpet again in 2007 I only found a couple of minor surface rust spots. Here are a couple of pics:

2005_0430055.jpg


2005_0430053.jpg


2005_0430062.jpg


2005_0430061.jpg


 

OLE PONY

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Wow, good call with the rust proofing Mike! That's awesome.
Thanks! Way back in 1974 I planned on keeping the car for a long time, after all, the 73 Convertible was supposed to be the very last Mustang convertible!!! But they made a comeback in 1983! I also had the Ziebart rustproofing done. It paid off, never any rust through in the whole car!

 
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71_badmach

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Wow, good call with the rust proofing Mike! That's awesome.
I was thinking the same thing! Just think if the factory had done us all this favor from the get go, and the cowl area!

 

goodnigh

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We used your basic "tar paper" underlayment as seen in the pictures (nice pics) and stuck it down with 3M 8090. All you can hear is the subtle hum of the Glasspacks. Who needs a radio, the car sings.

mike

 

luxstang

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As I did not want moisture to gather anywhere inside the car, I simply laid the carpet on the bare metal, without any insulation at all. That way, if it gets wet inside, all it takes is a warm day with the top down and the car is dry.

Sometimes I wonder if maybe I should have used sound deadener, though.....

 

OPN PONY

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I agree with everyone about Mike's idea to rustproof when the car was basically new: good idea. I wish someone had done that to mine, or at least taken the mouse and nest out from under the back seat:dodgy:. I can't complain as the floors aren't bad but not nearly as nice and clean as Mike's.

Thanks for the pics Mike. It helps me sort out what is normal on the floors. I wasn't sure on the big tar patches on the rear passenger floor around the drain plugs. The pics are a good reference.

Mike and goodnigh, where did you get the tarpaper underlayment kits?

Thanks,

Dan

 

OMS

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I agree with everyone about Mike's idea to rustproof when the car was basically new: good idea. I wish someone had done that to mine, or at least taken the mouse and nest out from under the back seat:dodgy:. I can't complain as the floors aren't bad but not nearly as nice and clean as Mike's.

Thanks for the pics Mike. It helps me sort out what is normal on the floors. I wasn't sure on the big tar patches on the rear passenger floor around the drain plugs. The pics are a good reference.

Mike and goodnigh, where did you get the tarpaper underlayment kits?

Thanks,

Dan
Dan, we [ should ] have them in stock.

If not I can direct ship it.

Don

 

OLE PONY

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I agree with everyone about Mike's idea to rustproof when the car was basically new: good idea. I wish someone had done that to mine, or at least taken the mouse and nest out from under the back seat:dodgy:. I can't complain as the floors aren't bad but not nearly as nice and clean as Mike's.

Thanks for the pics Mike. It helps me sort out what is normal on the floors. I wasn't sure on the big tar patches on the rear passenger floor around the drain plugs. The pics are a good reference.

Mike and goodnigh, where did you get the tarpaper underlayment kits?

Thanks,

Dan
I purchased my set from CJ Pony Parts when I was on a road trip to Pennsylvania with a big list of parts I needed, but I have used Don at Ohio Mustang for many parts as well. If you have your door and rear interior panels off, don't forget to buy the water shields.

 

Qcode351mach

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Tried a search thinking this had already been discussed but no luck.

Background:

What was supposed to be a freshen up paint job has turned to a more major project. My body and paint guy wanted the rear interior removed in order to cover paint right inside the door jamb. I peeled up the factory carpet underlay sound deadner and found a weak spot in a weird area. A mouse (or something bigger) built a nest under the driver's side rear seat and apparently either lived there a long time or drank heavily leaving behind a lot liquid corrosion because compared to the rest of the floor it is weak. Its only a small area and the rest of the floor just has surface rust but its time to sandblast, repair and repaint the floors.

Question: The factory underlay broke apart and a lot can't be reused. It seemed to hold moisture against the floor creating surface rust anyway. What have you guys used to replace the sound deadner insulation and are there any options that will avoid moisture probs but look sort of original?

I searched Don's website and it looks like there is an OEM style kit but out of stock for a 71-73 convertible. Has anyone used this style of replacement and if so how did it work? Does it seem to hold moisture?
The worst thing you can do is to put the factory type insulation back in the car UNLESS your doing a concours restoration & the car will be stored in a climate controlled area. It 1 of the contributing factors to why the floors rot out so bad.. The BEST way to protect the floors & improve the insulation / sound deading is as follows..Remove the interior components so you have full access to the floor pan..Wire wheel remove all rust..Apply 2-3 coats of rust bullet to the entire floor pan..repair any seams with flexo #12 epoxy seam sealer..Install ram mat http://www.raamaudio.com/products/RAAMmat-BXT-II.html You will now have SUPERIOR rustproofing /sound deading. Keep in mind that will protect the inside but you also need to do something on the outside (underside of the car)..I did my camaro with sem rust shield.. Great product !http://semproducts.com/Catalog.asp?prod=154 The stang is getting the underside done with rust bullet. Both of these products can be applied using a tight small foam roller & foam brushes..I haven't sprayed any of this stuff on both cars..All done using my foam roller technique.

I just did this to my 71 camaro & my mustang is being done the same way

You can see half of the floor done in rust bullet here



 
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turtle5353

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i used eastwoods sound deadner. Its really nice stuff and one kit is enough to do the intire floor pans. for about 150 bucks. its about 1/8 inch thick and is silver metal on one side and rubber sticky backing on the other side. Just peel the backing and stick it where you want and roll it in with a roller. conforms to compound curves very nicely and looks great when done. I have glasspacks on my car with headers and it cut the noise down dramatically and my feet used to cook when on long trips. But since i put that down my feet are nice and cool. Great product highly reconmend.

Kevin

 

OLE PONY

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I guess I was lucky with my floors on my 73 convertible and am only speaking form experience from one car, but I reinstalled the factory underlayment back in 1974 after only spraying undercoating on the floors to preserve them. The car was not garage kept until 1981, and then not all the time. It spent many years in storage (1994 to 2005) in a barn with a dirt floor, so not much moisture control there. I was extremly happy with their condition when I removed the carpet again in 2007! Anyway, I agree that cleaning the floors well down to metal and using the best rustproofing as recommended by Q is the best way to preserve them and is much better than the prevention I used in 74. With that said, I'm sure my floors will outlast me with the factory type underlayment.

In the picture below, the black overspray on the back seat support panel is the remnents of the spray undercoat that I used on the floor back in 1974.

2005_0430091.jpg


2005_0430051.jpg


 
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turtle5353

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I used a product called Lizard Skin. You can see a pic in my garage, but i'm in the middle of a road trip so no pics on hand
My buddy used that stuff and he loved it. said it made a huge difference in road noise and heat. He said it was easy to spray too.

 

URUGUAYAN_FASTBACK

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I used just some rubber type that is called Goma Eva in spanish... It is similar than the material used on the pad for the mouses in the computer you know?

In here, this material is used in some houses to insulate due to its acoustic propperties, the cheapness and the fact that water cant penetrate it...

Till now.. i´m happy :p

 
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In my restoration I am using the Lizard Skin product as well. Bought it through Summit who had the best price. I also bought the spray kit that comes with the gun. I am probably going a bit extreme, but I am going to use both the Lizard Skin and the factory underlayment. I am working towards a concourse driven restoration. I know the Lizard Skin will cost me a couple of points, but the benefit of it is worth it to me. Have a couple of buddies with kit cars and they preach by this stuff. They use both the sound deadener and the heat shield. One friend with a cobra kit and a big block states he can drive for hours without his feet getting cooked in the foot wells. Because it is a spray on application I feel it provides a degree of sealing protection as well. With the underlayment helping to prevent any abrasion from the carpet backing sanding it down over time, I think I will have a pretty long lasting solution. I will also use the Lizard Skin up into the inner quarter structure as well.

 
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