Fender removal forpre 81 w123 - PeachParts Mercedes-Benz Forum

Oracle12345 · #1 01-24-2009, 10:33 PM

What are some good methods for removing the compound holding the fender to the body?

t walgamuth · #2 01-25-2009, 10:16 PM

Its about impossible to remove some of the 123 fenders without destroying them. The undercoating is so thick and tough. I think yours is the later one though with the inner liner making it much easier to remove.

Oracle12345 · #3 01-25-2009, 10:17 PM

I have the undercoating on the 77 which I need to remove the fenders since I have some rust to take care of. Im not using propane torch since it didntwork to well on a parts care. MB says to use a heat gun. anything that will work while not destroying the fender?

KAdams4458 · #4 01-26-2009, 01:09 AM

Quote:

Originally Posted by Oracle12345

I have the undercoating on the 77 which I need to remove the fenders since I have some rust to take care of. Im not using propane torch since it didntwork to well on a parts care. MB says to use a heat gun. anything that will work while not destroying the fender?

Well, if MB says a heatgun will do it, then that's what I would do. Heat, scrape, repeat! Of course, this is gonna bite me in the rear eventually. I need to do a repaint on my '77 some day, and the fenders will need to come off. I am not looking forward to it!

bgkast · #5 01-26-2009, 10:18 PM

I need to pull the fender on my '79.

Not looking forward to it.

Oracle12345 · #6 01-26-2009, 11:07 PM

Got some rust in the areas behind the front weather gaurds. Got other body work to do so the fenders will wait and to be honest will the last places i fix too because its gonna take a lot of patience and time

beastopper · #7 01-27-2009, 10:42 PM

I have a 79 300D and I had to destroy the fender to get it off. I had to use a pair of 12" channel locks to peel the top lip free. On the other hand I have a 1983 240 parts car that I used to replace the drivers side front fender and it came off without a hitch. Also, I used the drivers side front and rear doors from the 83 240 and they fit perfectly. Thus, I have the passenger front fender, both doors, and both rear fenders available for resale if anyone is interested. I also have the trunk lid and hood available.

bgkast · #8 01-27-2009, 10:45 PM

Where is the part that is covered in undercoating, and why can't the seam just be sliced with a knife? I don't want to damage my fender, it's in good shape.

rs899 · #9 01-28-2009, 06:24 AM

I don't know of a knife that will cut through that incredible stuff.....I worked on a pair of W116 fenders in a boneyard for hours and finally gave up.

KAdams4458 · #10 01-28-2009, 06:36 AM

I was serious when I put the dry ice idea out there. No self-serve yard wants anyone out there with a heat producing device due to insurance reasons. Dry ice might just get the stuff cold and brittle enough to chip off in chunks. I think it's worth trying.

bgkast · #11 01-28-2009, 12:50 PM

Quote:

Originally Posted by rs899

I don't know of a knife that will cut through that incredible stuff.....I worked on a pair of W116 fenders in a boneyard for hours and finally gave up.

If it's like the undercoating on the rest of the car a knife should be able to cut it just fine. I used a knife, heat gun and scraper to remove it when I was doing some patching on my floors.

rs899 · #12 01-28-2009, 01:20 PM

Yeah, its the same stuff, but about 1/2" thick. Without heat to soften it (in a upullit) I can't see how anyone could do it.....

DIESELVOLVO · #13 01-28-2009, 02:43 PM

I just did some floor repair on my 82 in an area where some of the coating was easily 1/2" thick. I had good luck (finally) using a razor knife with a new blade. I would make a series of slices, starting shallow and increasing depth on each pass, until I got down to the metal. Then I would make a new slice parallel to the first with about 1/2 inch between the two runs. Then you can gouge out down to the metal at the end of the run and peel the whole 1/2 inch wide strip off. Worked for me but am not saying it was easy at all. Great stuff until moisture gets between it and the metal then it becomes a restoration nightmare. For clean up to get some bare metal so I could weld without catching everything on fire I just used a wire wheel on a 4.5" angle grinder. That worked well as long as I kept moving around so as to keep the stuff from heating up too much and smearing.

KAdams4458 · #14 01-28-2009, 05:23 PM

Quote:

Originally Posted by DIESELVOLVO

... For clean up to get some bare metal so I could weld without catching everything on fire I just used a wire wheel on a 4.5" angle grinder. That worked well as long as I kept moving around so as to keep the stuff from heating up too much and smearing.

Another applicable idea! I just remembered that I took a drill with a small wire wheel to a few damaged areas of undercoating where rust was just starting to form on my '77, and I noticed the same thing. It brushes away, but then heats up and starts smearing and flinging. Could be time consuming in a salvage yard, but a cordless drill, or better yet, a cordless angle grinder with a wire wheel could eat through the undercoating.

Warning: based on my experience with cleaning off the undercoating on my rocker panels, once it gets hot and starts flinging all over, it will never ever come off of any clothing you might be wearing. Safety glasses are not immune, either, as I ended up tossing mine. It doesn't wash off skin or hair very well, either. In hind sight, you might want to avoid getting it too hot with a wire wheel.