Tar on the interior sheet metal

T

Tom Z...

Member
It might have have been discussed before, but I am new to the site. How do you remove the thick tar that Ford put on the interior sheet metal. What was the purpose of it? Tom Z...
 
It was used as an insulation as well as a sealer. Examples: around edges that were not stitch welded the entire length and holes along the belt line used for trim clips.
Removal is tedious but not difficult. A decent heat gun and putty knife will get the bulk of it removed. If you must remove it completely, any tar remover or simply gasoline (carefully used) will do the trick.
 
Last edited:
IT WAS CALLED UNDERCOATING,to prevent rust hopefully and soundproofing.bodyshop suppliers and part stores sell a solvent to remove
 
It was used on large panels such as doors to reduce the "drumming" that can occur from road vibrations. I suspect it was also intended to make the sound of shutting the doors more substantial to indicate quality. If you remove it, it will change the sound. Unless you need to get to the backside of a panel, removing it is more trouble than it is worth.
 
supereal said:
It was used on large panels such as doors to reduce the "drumming" that can occur from road vibrations. I suspect it was also intended to make the sound of shutting the doors more substantial to indicate quality. If you remove it, it will change the sound. Unless you need to get to the backside of a panel, removing it is more trouble than it is worth.
Click to expand...
Super is correct of course. This material was applied strictly for the purpose of sound deadening and in some cases a sealer as I'd noted in a previous post.
Anyone that has restored one of these early Fords has surely noticed that the material is applied very near the center of panels and NOT anywhere near the bottom where one might expect rust to begin.
 
The 49 through 51 Mercury cars had the whole inner floor covered with the stuff and it was a corrosion builder after it aged and cracked allowing moisture to enter. Undercoating was optional in that time frame as I have a 51 Mercury with and one without the coating. The one that is undercoated had terrible cancer in the inner and outer rocker panels. The one without only has mild corrosion in the same areas.

I used scrapers and wax & grease remover to soften the stuff then it scrapes right off. It's a mess to clean up. The modern butyl rubber on aluminum foil like D-Mat an 2nd-Skin are a good replacements to keep the heat and road noise down inside the car.
 
We old body men often had to remove the undercoat to repair the area. Here is how ; heat the other[OUTSIDE] side of the panel We used an ox act bushie flame start at the bottom as heat travels up. quickly move the flame over the area it is not necessary to damage or discolour the paint .Once the bond of the undercoat to the metal has been softened the undercoat will scrape off with no mess .
 
Been there.What I found that works best is a Multi-Function Power Tool from HF.Makita and Dremmel makes them as well but the HF tool is about $20.The number is 67256 and you will need an angled convex segment blade#67492.It peels the undercoating off like crazy.If memory serves correctly,I did my 5W in a couple of hours and used 2 or 3 blades.It's fast,fun and noisy.No fumes,clean and safe.
 
Do you Know anyone that can do dry ice blasting? It will remove the tar and leave any paint underneath.
 
Hi:
I've removed more than my fair share of old , dry undercoating from "up north" Fords and Mercurys. After messing around with solvents I used my air chisel with a wide blade and it knocks off undercoating in a heartbeat. Round the blade edges a bit so it doen't dig in and you will wonder why you spent all that time making an oily mess with gasoline etc. You will get some minor scratching on your panel interiors but primer and paint will handle that. Lefty Rodan
 
I have a question about all of this. Is the purpose of removing the old material so that you can put a more modern material in its place, or will the newer material stick onto the older material?
 
In my case, I had to remove it to treat and repair the corrosion that was underneath. If it hadn't aided the corrosion, I'd have left it alone but the damage was already done.
 
rotorwrench said:
In my case, I had to remove it to treat and repair the corrosion that was underneath. If it hadn't aided the corrosion, I'd have left it alone but the damage was already done.
Click to expand...
That's precisely why I always remove it. I can not imagine putting all of the effort in to one of these restorations and NOT seeing what's beneath that coating.
 
You must log in or register to reply here.
Back
Top