Just found rust on my W123, need advice - PeachParts Mercedes-Benz Forum

davidd · #1 10-21-2006, 11:37 PM

Hey, I accidentally posted in the restoration forum instead of over here.
Just found rust on my W123

Copy and pasted from there.

Hey, I just bought a 1983 300D and I just took out the carpets to clean them and I had a few little surprises there to bum me out. I have a couple holes in the floor behind the driver's seat. Two holes are located to the front and rear of the part that bolts the driver's seat to the car. Those holes worry me the most as they make me think of the rear corner of the seat falling through the car, which by the way is me freaking out more so than I should, cause the hole is only 1 1/2 inches long.

I was recommended POR15 to fix up the rust holes and spots but I wanted to see what people here think about these holes.

Overall photo of rear floor

Close up of holes 1 and 2

Close up of hole #3

And the view from under the car looks worse

And now two spots of rust on each side of the rear wheels.

Some rust on the front floor

And lastly some rust and a hole on the front door

That's all the rust on my car. I want it all gone. If I can use POR15 I'd be happy to. Does anyone think I need more than just that?

I'm only really worried about the holes where the driver's seat is bolted down. If anyone has some advice please share it.

Thanks in advance,
David

Pete Geither · #2 10-22-2006, 08:06 AM

In my opinion, holes in floors are a serious problem especially around seat anchors. Any sudden change in direction or speed could send the seat through the floor,,, not a good thing.

The floor needs to be inspected and new metal welded in the bad areas to get the integrity of the floor back to where it should be. POR 15 is good to stop surface rust but should not be used to repair holes or thin metal.

Dusty-NZ · #3 10-22-2006, 05:12 PM

Oh dear ... COME ON DAVIDD .. (shouting) .. you know the answer already .

Mercedes built your lovely car with a passenger safety capsule .

Holes in the floor undermine the integrity of that capsule .

DO THE JOB PROPERLY. Cut the rust out and weld new metal in!

You cannot fix a hole in the metal with liquid in a tin. WELD A PATCH IN.

You've got a great car , if you do the job properly , it will stay a great car for longer.

Rant over ..............

davidd · #4 10-22-2006, 06:04 PM

Both of you have told me exactly what I originally thought I needed to do... but then I was told I was overreacting and POR15 would be sufficient, and the whole time I felt that seemed like a quick fix. I mean, for the rust on the door, that's probably fine, but I had a weird feeling in my stomach about using some epoxy to cover up a hole that is keeping my seat from falling through the car floor!!!

Thanks for helping to knock the sense back into me! I've never done steel work before, so I'm taking the car into a shop tomorrow to get a quote and hopefully get it fixed tomorrow as well.

This is exactly why I posted this here, I wanted honest feedback and that's what I got. Thanks,
David

davidd · #5 10-24-2006, 03:16 PM

What sort of price should I be expecting to pay to fix this at a body shop? I've called a few places but I haven't been able to go in for an estimate.

One place told me over the phone "how much are you willing to pay because that sounds like it will cost a lot" which of course has me worried. I didn't think this would be that expensive to fix.

Basically if anyone could tell me about how much they think this should cost to repair, that would be great. I want to make sure I don't get ripped off.

Thanks,
David

riethoven · #6 10-24-2006, 03:33 PM

Quote:

Originally Posted by davidd

What sort of price should I be expecting to pay to fix this at a body shop? I've called a few places but I haven't been able to go in for an estimate.

One place told me over the phone "how much are you willing to pay because that sounds like it will cost a lot" which of course has me worried. I didn't think this would be that expensive to fix.

Basically if anyone could tell me about how much they think this should cost to repair, that would be great. I want to make sure I don't get ripped off.

Thanks,
David

That is a very subjective question. Most paint and body shops just want to paint cars and are hesitant to do rust work like that. Maybe you could do all the prep work including fitting all the patches and then take it to someone you can trust to spot weld the patches in. These are very easy repairs and can't really be seen from the outside of the body. I think 3M even has 2 part adhesives that can be used to glue steel to steel. This would eliminate the welding part of the job. As far as the painting, you can have spray cans of color matched paint at the auto body store and primer should be off the shelf.

And you will do a better job because you really care about your car more than anyone else.

Pete Geither · #7 10-24-2006, 07:34 PM

We fix tons of floors and frames and what Doug said is true. If you get the areas all prepped and ready for us to cut and weld, you will save money. The only part I disagree with is the glueing new patches in part. I firmly believe the areas around the seat should be welded, seam sealed and coated with a good 2 part primer and undercoated. Getting the old undercoating and paint off can be very time consuming, and time is definately money.

davidd · #8 10-24-2006, 07:44 PM

Went to a body shop pretty close to my house today and they told me I should replace the entire driver's side floorboard. He said I should go to a junkyard and get the floorboard and bring it in and he'll weld it in for $300. I called a local Mercedes junkyard and they said they had rust free floorboards and that they would sell me the driver's side of one for $250.

So I'm looking at $550! I'm going to get a couple more quotes tomorrow.

Man, this is so not what I needed!

Does this sound about right to everyone? Is redoing the whole thing overkill or does that sound good?

David

teeman914 · #9 10-24-2006, 11:00 PM

David, I'm newly registered to this website - I think it's great. I have been looking at the entries in this forum for the last few weeks. I'm reserching my purchase of a 240D or 300D. I have found there are rust problems with these models especially in the northern midwest and the northeastern part of the United States where salt is used for snow melting. Your particular rust problem - that you detailed very well with photos - made me want to run to get my dremel tool. If you are not familiar - It is a small hand held rotary tool. $50 - $100 depending on what store you buy it at (eBay, Sears, Home Depot). One of its greatest uses is to cut metal very precisely. I've cut bolts off in a few seconds. It cuts sheet metal like butter. I would get a piece of sheet metal (sheet metal is cheap) of the gauge the floor is in this car. Not sure of the gauge - maybe one of the more expert members of this forum could help with this one. Cut maybe a 4" to 6" square. Use the cut piece as a template for cutting the portion of floor. Mark it with a Sharpie pen. Then cut the floor portion out the exact size of the patch. There has got to be a welder that would be willing to do a 5 minute weld job for well under $100. Drive carefully to the welder with a piece of wood covering the hole and the 3 other bolts holding your seat in place. Upon your safe return mark the seat rail hole and drill a hole of the same diameter. Bolt with a fender washer - large washer, bolt size hole - and a regular washer from the underside. Sand off the patch - prime and paint. I wouldn't sweat the color match. Who's going to see it. Paint it black. Half day of work and maybe under $100. Plus you get one of the all time greatest tools in your tool box. Let us know what happens whatever you decide to do.

davidd · #10 10-25-2006, 12:58 AM

teeman914, I'm very intrigued by your suggestion...

If I was to do it this way, how would I cover up the holes on the underside of the car? Same way? By cutting out the metal at the bottom and placing a curved piece of sheet metal? Or would I want to do the underside differently?

Thanks,
David

Pete Geither · #11 10-25-2006, 05:34 AM

16 gauge metal will work just fine.

teeman914 · #12 10-25-2006, 10:45 PM

Hi David,

The patch for the area where your seat bolts to the floor could be cut from the top or the bottom. It looks to be relatively flat. Small bends could be beatened into the patch with a hammer and something solid like a vise. Thanks to Pete's info it is about 16 gauge thick - single layer. When you cut it will cut through top to bottom. I would think cutting from the top would be more comfortable. Watch for sparks. That little Dremel tool rotates at a very high rate and it will put some sparks into the air. Also, be careful of the fuel line. I'm not sure where it is on this model, but find it and be careful not to cut into it. All other areas in the cabin could be done in the same way. The area by the back wheel well is a different story. You could cut the area out with the Dremel tool from the outside, but forming a flat piece of sheet metal to fit might get ugly. I have seen pre-formed sheet metal pieces for other cars for areas like this. Other problem areas are rocker panels and window seals. I'm sure you can find auto part sources that supply these pieces on the web or in the Yellow Pages - or maybe one of the very knowledgeable forum members has a source. Especially for models like the 240D and 300D. If you find pieces like this, get the piece first and use it as a template to cut your area of the body out. The Dremel tool - with the cut-off wheel attachment - can make very precise and clean cuts into sheet metal. Let us know what happens.

Teeman

Pete Geither · #13 10-26-2006, 05:33 AM

Make sure you protect yourself with good goggles, clothes all over and gloves. When those cutting wheels come apart they can be devastating. A person I know was spinning one on an air tool, probably over reved it, and it came apart, and hit him in the balls. He has been laid up for nearly a year and doesn't know if he will ever fully recover.

davidd · #14 10-26-2006, 02:17 PM

Here's a couple quick questions...

The front floorboard on my car.... most of the top layer has come off (the one which is supposed to be painted the color of my car), and most of the black layer is crumbling away. What should I do to fix this area? Is this what is referred to as the foot well?

Would the foot wells from K&K which I've seen people talk about on this forum be able to replace that?

Second, drain holes in the foot wells. Mine are wide open, as in I can see the ground through them.... is there supposed to be a plug in there? If so, where can I get replacement plugs (the dealer most probably, haven't seen them in any online stores)??

And lastly, the holes on the outside of the car... would replacing the rocker panel be a fix for those?

Thanks for all the help everyone, I'm trying to learn all this new terminology and everything and I wouldn't be able to do it all without the help from this forum!

David

davidd · #15 10-26-2006, 06:30 PM

The rocker panels are fine, had it checked out today.... the holes are right past the rocker panels.... well, now I know what the rocker panels are exactly.

Hmm, went to a couple recommended body shops today (one by Mr. MB Motors and one by the dealer near me), neither of which would fix the holes, both of which told me I'd have to go to a restorer or do it myself. The first place told me I should replace the whole floorboard, the whole thing. Said I should look at paying $1500-1800. Holy crap, I'm not down with that. Second place told me to do it myself like you guys have recommended on here (cut out around holes, have welding shop weld on new sheet metal).

So much conflicting advice from different places.

David