[Bet Winner]

I have had my Judge for 30 years, but never removed the undercoating, but I'm getting ready to do just that. I don't really want to go to a nationally judged show with undercoating on the underbody and gas tank. (I'll get a repo gas tank.) And this undercoating has discouraged me from completely detailing the underside. I have removed the gas tank and 90% of the area exposed is red oxide primer with some very light black shot on it and Carousel red on the sides of the sections of the underside of the trunk that dip down. I have removed a little of the undercoating behind the rear end and found the same with a big spot of Carousel red at the lowest vertical area of the body just in front of the trunk. I don't know if the remainder of the body will look this good or not--it's a mystery right now.

But I need an easier method to do this, and I'm sure some of you have had good/bad results. I want to leave the factory paint there and either paint over it or leave a lot of it if it still looks good. I will at a minimum need to remove some scale from areas that were not undercoated well, but believe me, most of the body itself is coated.

I'm leaning towards Eastwood's kit that includes a heat gun and some spray that supposedly removes undercoating. I used a hair dryer to test and it did make a small spot of the undercoating soft enough to remove with my fingernail. I have heard of people using kerosene (but this is not working well) or lacquer thinner (this is also somewhat slow, and I suspect I'll die from the fumes before I'm done) I have read that some have used a needle scaler, but I assume that will remove what factory paint is still lurking underneath.

So, please give me your opinion, or at least let me know if you have tried Eastwood's kit or a heat gun to do this. I believe if I can soften it some, it will scrape right off......................with some work...............ok, a lot of work.

Why did I wait til 49 to do this?

[1971/455/HO/4-SPD]

A cheaper way to go is a hand held propane torch and a scraper! Works great for me, just don't heat it up too much!

[Bet Winner]

Originally Posted by 1971/455/HO/4-SPD

A cheaper way to go is a hand held propane torch and a scraper! Works great for me, just don't heat it up too much!

That sounds a little scary, but will probably work. Let me know if you hurt any metal, removed factory paint. (Edit: You're more brave than I!)

I'll also use this time to replace the original fuel/brake lines and take the rear end out to paint it and the springs. (Someone may tell me to replace the rear springs, but the car sits "just right" so I want to reuse them.)

[1971/455/HO/4-SPD]

Originally Posted by Bet Winner

That sounds a little scary, but will probably work. Let me know if you hurt any metal, removed factory paint. (Edit: You're more brave than I!)

I'll also use this time to replace the original fuel/brake lines and take the rear end out to paint it and the springs. (Someone may tell me to replace the rear springs, but the car sits "just right" so I want to reuse them.)

Nope! Like I said, you can control how hot you get it by how thick the undercoating is! Obviously, make sure there is no gas or flammable liquids in the tank, etc.

[JLHarper]

If you follow the link to that 70Z28 found in a garage with 1100 miles on it....in the lobby I think...it was sold or sent to a CAMARO resto shop where someone asked the guy how to get undercoating off....

Sounded like he has done it before.

I will see if I can find the thread.. Maybe you can PM him, I think hes in the resto business. He might provide better details or options.
Jeff

EDIT: Its # 371517 by CHARLIE LILLARD (sp) He says:

No. The undercoating is part of the history of the car. No reason to tamper with it. If the car had been messed with I would do it but this thing deserves to be left alone.

I have removed undercoating on other cars by using white gas, kerosene, WD40 etc to soften it up and then a high pressure steam cleaner. Any petroleum distillate will soften it.

[goatnut]

Sounds to me the car is still nice on the under side. Like the JLH's post above said its part of the cars history I would most likely leave it if it still looks good - not peeling or flaking.
I did remove the under coating on my car because of peeling and light rust creeping under the under coating I used the propane torch and scraper. Just becareful not to get burned by dripping hot tar and use a respirator or mask the stuff will make you dizzy. Heres a couple of after pics.

[Bet Winner]

Originally Posted by goatnut

Sounds to me the car is still nice on the under side. Like the JLH's post above said its part of the cars history I would most likely leave it if it still looks good - not peeling or flaking.

I don't believe my car was undercoated at the factory--maybe at the dealership or maybe slightly later--not sure. So I consider it to be a piece of my car's history that needs to be returned to factory original--kind of like finding that factory correct horn relay.

If it was done at the factory, or I knew it was done at the dealership, I might feel differently. I have the original sales invoice for the car, and the original owner did not pay for it in the original deal.

[bulletpruf]

If you have sharp edges on whatever you're using to scrape, grind them off so you won't leave gouges in the metal.

Will be removing the factory undercoating on my '71 GTX in the next few weeks; should be lots of fun.

Scott

[goatnut]

I have never heard of factory undercoating only sound deadner. The original owner may/may not have returned at a later date for the undercoating. I worked at a couple of new car dealerships and its not uncommon to have a customer return the car later for undercoating due to service schedule or what ever department does the undercoating. Alot of times customers come into my shop with there new cars and no undercoating and I tell them it's best to have it done the sooner the better due to our area and the amount of brake and fuel lines that we replace because of salt/rust. Granted these are just every day drivers but so was a 69 judge in 69/70. On the flip side I also see your reason for wanting it off. It will look 100% better off on a concourse show car but the fun is in driving it there.

[JLHarper]

I remember the ZEIBART undercoating they would try and sell you in the 70s before you left the lot.
Man, they were agressive in selling that dealer add on, but pure profit I heard.

That Z28 had some about everywhere, even on painted surfaces.

[Karfever]

I tryed the eastwood product...save your money IMHO.

[Baron Von Zeppelin]

ouch ... you really want to do this BW ?
It sounds like 200 hours of self inflicted torture.

The best way i can think of involves buying a top notch rotissery.
Removing interior, radiator, drivetrain, exhaust, axle, all lines, master cylinder and rear bumper.
Then spin car 90 degrees over, and work from the tunnel - down.
Spin to opposite side up, and work from tunnel - down.

You'll be able to detail the heck out of everything you remove, but thats all in addition to the first 200 hours mentioned.

A project like this could stretch from 9 months to 6 years in spare time.

Your car is already super super nice. I've never paid much attention to the underneath of anyones car unless they had mirrors under it. Even then I just give it a passing glance.

I'd rather pull the lines, tank, exhaust, axle, rear bumper - smooth it with a sander and give it a fresh coat of chassis black like a frame-on restoration. Then put your new/detailed items back in and look fresh enough to please 99.5% of all viewers.

JMHO

[Bet Winner]

Originally Posted by Baron Von Zeppelin

I'd rather pull the lines, tank, exhaust, axle, rear bumper - smooth it with a sander and give it a fresh coat of chassis black like a frame-on restoration. Then put your new/detailed items back in and look fresh enough to please 99.5% of all viewers.
JMHO

I do plan to remove those things and would like to remove the undercoating at the same time. I don't mind scraping if something will soften it up some. I also need to clean/sand some areas that were not undercoated. If it has to be chipped off because it is hard, I could see it lasting way too long.

But, I've never done this so I may be wrong about the time, and spare time is at a premium around here. I took Little Wife to the basement to show her the virgin belly that the gas tank was hiding--she didn't seem to get it

[Bet Winner]

I've seen some other methods--

Spraying paint thinner or kerosene from a sprayer (I was just using it on a rag and wiping)
Spraying WD-40 or brake cleaner
Spraying Mr. Muscle oven cleaner because it does not require heat to work

I'll try a few of these before I go the heat route.

The guy that used the Mr. Muscle sounded very pleased.

[north]

My 2 cents

Leave it and buy a car that wasn't undercoated!!!!

Seriously though it is a major pain.

My 69 Hardtop is from arizona (Tucson) and the dealer undercoated it new (have the bill) Thank God the car was protected from the corrosive conditions of Tucson.

Short of a concours car I would leave it.

If you do remove it the best way I have found is the propane torch (just enough to warm it up) and a plastic scrapper.

[1971/455/HO/4-SPD]

Originally Posted by bulletpruf

If you have sharp edges on whatever you're using to scrape, grind them off so you won't leave gouges in the metal.

Will be removing the factory undercoating on my '71 GTX in the next few weeks; should be lots of fun.

Scott

MMMMMMMMMMMMMMMMMMMM, there's nothing like the smell of fresh MOPAR undercoating burning in the morning................

[gearhead78]

To protect the under surfaces I have used a heat gun and a wood paint stick to get 95% off. The other residue comes off with a little wax and grease remover.

If you are going to repaint and dont care about the finish underneath use a propane torch, scraper and finsh off with a wire wheel on a grinder.

[Bet Winner]

Originally Posted by north

Short of a concours car I would leave it.

That is my intended destination with the undercoating removal and other under the car work.

I really still need a correctly dated water pump and parking light lenses with "69" in them instead of "70". Maybe one or two other incorrect items will surface, but I believe that most every part and date code are correct. (The shifter date code is off, although a 69 shifter, and wheels a little early, but most parts are original.) I have found the correct wheels, shifter, horn relay and master cylinder. I will need a repo exhaust (had a stainless system bent in 1983 before repo's), tires and battery near the end--assuming that I make it.........................

I guess that I'm shooting for the 2010 convention.

[Bet Winner]

Originally Posted by gearhead78

To protect the under surfaces I have used a heat gun and a wood paint stick to get 95% off. The other residue comes off with a little wax and grease remover.

If you are going to repaint and dont care about the finish underneath use a propane torch, scraper and finsh off with a wire wheel on a grinder.

Thanks, gearhead! This is exactly the kind of advice that I needed. And thanks to everyone else.

I want to preserve the finish underneath if the rest of it is nice, and I have already seen that some heat makes this stuff soft enough to rub off when I used the hair dryer for a while. If my experiments with WD-40, brake cleaner, Mr. Muscle don't work, I'll probably buy an adjustable heat gun and rely on it.

[johnmilza]

A friend of mine told me this works well (http://buy1.snapon.com/catalog/item....re&dir=catalog) Haven't tried it myself.