Can anyone help me with what to use to remove 60 year old hardened undercoating that has been applied to the underside of my hood? Thanks.

 

hello i heard a torch,you heat it little by little

 

I had this on the bottom of my cab. Sandblaster didn't work . It was cracking up so i used a wide chisel to get the most of it then a grinder.Then blasted it again. Lots of work.

 

I wouldn't recommend heat or anything that generated heat because you may warp the metal. I have removed various coatings using solvents. Since the hood was never undercoated at the factory I have never had the opportunity to deal with removing undercaoting from a hood but if it were me I would remove the hood, turn it over and apply a good paint remover gel to the undercoating. It may take a couple of applications but it should do the trick with the least amount of damage to the metal of the hood.

 

Thanks for the help. Before using heat (probably a heat gun first), I will try the paint remover method. Hope my arm doesn't fall off working it.

 

sorry for my misleading info...i think they used a torch on places like chassis not sheet metal....Charlie is absolutely right,dont risk warping your hood....elbow grease and chemicals is the best have you tried pressure washer?...

 

I used brake cleaner and many hand held wire brushes. My Canadian Built truck was 1/4" thick in tar/oil based stuff, at least it kept metal replacement work to a minimum, but not easy to remove. Remember to use proper safety equipment, eyes, hands, the better the solvent works, usually the worse it is for your body. Cheers.

 

No, I haven't tried a pressure washer -- I think it's worth a try....in the Spring, though. Too cold now here in the northeast.

Thanks.

 

Thanks for the advice on the brake cleaner method. After trying the pressure washer, I will be lining up chemicals in order of least harsh to most harsh, working my way up. I promised this guy that before I gave him the hood, I would remove the old undercoating.....didn't realize the size of that promise at the time.

 

I had a simalar issue with my 66 Mustang, undercoating everywhere. Sandblasting would not work, so out of desperation I grabbed my little propane torch and a gasket scrapper and it worked very well. Just use very little heat, barely touch the undercoat than try scrapping and if still hard hit it again with heat. Just be sure to point torch away from metal while scrapping to minimize heat, also do a small area and move to another area like you would for welding. Use as little heat as possible.

Good luck,
Paul

 

Thanks, Paul, for the advice.

 

Torch and flat blade scraper..And it don't take much heat... If your concerned that it might get to hot wet a towel and place it on the opposite side to absorb some of the heat......Good luck

 

If it's the same stuff that's on the inside of the doors, I just used a stiff putty knife and scraped it off and them wiped the metal clean with lacquer thinners. Didn't really take to long to do. Not sure what the heat gun would do, might end up with a sticky mess.

 

Don't use heat near the brake cleaner, I can't think of the name of the chemical in it but it's DEADLY when inhaled.

 

Wait until you get a warm, sunny day in the spring, and leave it out in the sun. Once it's good and warm, it will just scrape off with a 1" putty knife. You will have to dig at it at first, but once you get under it, you will be able to flake it off pretty quickly. Just make sure you let the sun keep it as warm as possible.
Chuck