replace the whole rocker, I assume? - PeachParts Mercedes-Benz Forum

WANT '71 280SEL · #1 03-10-2010, 08:33 PM

The weird thing is, the rust is isolated to the top of the rocker. The jack points and the ends, in the wheel wells, are rust free. The car has been repainted, maybe someone just went to bare metal then didn't treat the metal well before laying on the paint?

Any idea what is costs to have a rocker welded in? I realize I just posted about my w111 floor pans, but I'm now considering adding this car to my stable. I hate this feeling. Do I split my time and money between fixing up a 108 or focus on the 111 I already have? It's the 111 that needs the floor pan/s.

Thanks,

David

WANT '71 280SEL · #2 03-10-2010, 08:43 PM

Here's the photo. The LR is completely free of rust, btw. The right front door sill/rocker has rust, too, but not this bad.

The car is located 100 miles away from me.

thorsen · #3 03-10-2010, 08:52 PM

I don't know how much it would cost you to have a new rocker welded in. I welded in new rockers and patched some holes in my W114 and there was a fair amount of work involved. I could not even imagine how much a shop would have charged me to do the work. It would have cost far more than the car was worth - I am sure of that.

SPDMETL · #4 03-10-2010, 09:38 PM

One thing you want to remember about rust-there's more. There's always more. Have you had this car on a hoist ?

JiveTurkey · #5 03-10-2010, 10:29 PM

I'm now officially done ever complaining about my w114's "rust", you win sir.

WANT '71 280SEL · #6 03-10-2010, 10:41 PM

The weird thing is that there isn't rust in the normal areas. The quarters and fenders are in great shape, as are the rockers (minus the shown spot, of course). If I get this car, I don't know that I'd replace the whole rocker. Who knows. I'll look at it more closely then report back here.

Thanks,

David

PanzerSD · #7 03-10-2010, 10:52 PM

Quote:

Originally Posted by WANT '71 280SEL

The weird thing is, the rust is isolated to the top of the rocker. The jack points and the ends, in the wheel wells, are rust free. The car has been repainted, maybe someone just went to bare metal then didn't treat the metal well before laying on the paint?

Any idea what is costs to have a rocker welded in? I realize I just posted about my w111 floor pans, but I'm now considering adding this car to my stable. I hate this feeling. Do I split my time and money between fixing up a 108 or focus on the 111 I already have? It's the 111 that needs the floor pan/s.

Thanks,

David

If rusty on top and not at jack points or anywhere in the botom, then someone has already replaced a rocker, welding only the bottom on and leaving the top on the car and NOT treating it for rust. It will end up being a new rocker. cheaper, faster, easier.

sjefke · #8 03-11-2010, 12:21 AM

Looks like water (and salt?) collected and sat under the rubber causing rust. My rear floor panel looks like that due to MB foam mat (aka sponge). I would suspect the rest of the car too, despite of what it may look like. Bring magnet and bang with hand on outer rockers to see if anything shakes loose. Jack the car up on its jack stand. Crunching sounds will be a good indicator of more rust problems. If all is as good as you say, then depending on what you want to do with the car, you could just clean up the top rocker area. As long as the material is not too thin across the board, it can be repaired by patching by welding here and there.

Bert

tr1cky · #9 03-11-2010, 09:08 AM

I grew up in the Northeast and owned my fair share of rust infested rides. I swore that I wouldn't ever play the rust game again. The rust always wins. In the Southeast I've been lucky enough to find two older Benzes in a row that are rust free.

Body shops are not interested in rust repair. This is often something that now must be tackled by someone with time, patience and determination.

Squiggle Dog · #10 03-11-2010, 10:12 AM

My 1968 200D has the same problem. Overall the car is not rusty. My driver side outer rocker panel is very, very, badly rusted, but the jack points are solid and the inner rocker appears to be solid also. I think it also is lack of proper paint preparation or painting over rust. I believe that replacing the rocker panel and treating the surrounding metal will solve the problem and I will probably replace it myself before I try to sell the car again since people see that spot and assume the rest of the car is totally rusted out.

meltedpanda · #11 03-11-2010, 08:27 PM

thats a big job to be done correctly , IF you can find a body shop that will take on a unibody rocker panel. My guess would be 750$

have mercy · #12 03-11-2010, 08:56 PM

Yes thats the thing, if you weld [or use any kind of heat]on the inside of the subframe you have a heated up metal surface with nothing on it . No primer it will rust out where welds are from the inside out. My 190d sunroof has major repair underneath. Both rear suport arm have fallen [fixed 25yrs ago], jack holes-0-,all 4 floorboards replaced. it ride's good and does not cut tires.

sjefke · #13 03-12-2010, 10:51 AM

Probably more than $750 because for a proper outside rocker repair you often have to take off the front fender and some run inside the rear fender too, so you (or shop) may need to cut and patch lower quarter panel of rear too to fix rocker. I always prep any metal I weld and cannot get too with zinc por epaxy primet, and then again spray zinc primer or some other rust preventer in there after I am done welding to seal the welds on the back. You can never put too much rust preventer on bare metal after it has been heated. It needs to be done immediately because it will rust very fast.

Although not recommended by experts, I have used galvanized steel as well to patch. Creates yet another layer of rust protection, but you STILL need to put a good zinc based primer on it because around the weld, the zinc/galvanized coating will burn off.

Bert

mercmad6.3 · #14 03-13-2010, 10:17 PM

I have done dozens of these on W111's . It's easier to cut the rusty bit out and weld in a section. Replacing the W111 rocker is a seriously big job. Once the rusty bit is out i look inside and check the overall condition. In the wheel house in the front of the rocker are two small panels that block the cavity. Remove those and you can see into the rocker. I also get a water blaster and wash the mud out,let them dry and check again. The Metal is very thick ,even on the sedans so welding in a section is perfectly OK. Once the sides are back to normal and before the end plates are replaced,spray the inside of the rockers with one of the many products designed for this. ( Dinitrol,Waxoyl etc etc ) or if you can't locate a dealer close to you with that stuff, use a 50/50 mixture of Diesel fuel and axle grease. Heated gently to make it liquid and sprayed into the rockers,it will be there for years. The Front panel on the rocker is often the reason for rust. Stone chips in the underseal aren't repaired and they rust through,eventually water gets in there and rust in the rocker cavity is the result.
The rockers should have the end plate etch primed,painted then covered with Wurth 'body Shutz' then painted body colour. This will prevent rock damage for the future.
Unless the car is placed on a Caroliner jig ( or similar ) the oppurtunity exists for the door alignment to go out when the entire rocker panel is removed.
if you know a plumber,ask to use their drain cam so you see inside the cavity if you want to check closer for rust.

mercmad6.3 · #15 03-13-2010, 10:19 PM

Quote:

Originally Posted by sjefke

Although not recommended by experts, I have used galvanized steel as well to patch. Creates yet another layer of rust protection, but you STILL need to put a good zinc based primer on it because around the weld, the zinc/galvanized coating will burn off.

Bert

The best tro use is a sheet steel called Zinc galv . It's a C3 steel coated with zinc and is perfect for autobody rust repairs.