2005 W211 rust!!!

[Timeandleisure]

I am going to have a go...my rust is starting to bubble near where the roof joins the pillars And around the aerial...

 

[Kev555]

Even galvanising did not stop them rusting.

Galvanise the right metal and it wont rust!

 

[rf065]

small panel at front of rear wheel i stripped back to bare metal last year and found a rusty water mark under the perfect paintwork in the middle of the panel

When my CLK rusted at just over 4 years old, the body shop said there had been moisture on the panels before it was painted in the factory. So, use cut price steel, spray it with moisture already present and you can see why galvanising still could not stop it rusting very quickly.

 

[Craiglxviii]

When my CLK rusted at just over 4 years old, the body shop said there had been moisture on the panels before it was painted in the factory. So, use cut price steel, spray it with moisture already present and you can see why galvanising still could not stop it rusting very quickly.

It wasn’t cut price steel. It also wasn’t as simple an issue as “use cheap materials” for MB.

Firstly. Daimler Group buy all of their commodity metals worldwide under a group purchasing scheme. The metals are bought to highly exacting specifications, and the Group is big enough to represent significant annual steel tonnage in its own right. Daimler buy primarily from the likes of Benteler, Artelor Mittal and ThyssenKrupp, companies not exactly known for shoddy materials.
Secondly, the process by which steel is made somewhat precludes “shoddiness”, as in if a mill is making high quality metals, they won’t (can’t) just stop and switch to making “cheap steel”. The steel is milled, processed and coiled like paper, all in a continuous process. Some mills only make exactly one grade of steel for this reason- they work to the volume limits of their capacity. So, the quality deviations in material that Daimler bought/ are buying to are minimal and subject anyway to Daimler’s own quality standards.

Now we come to the tragic bit, as the Engineer’s Song goes. At some point in the early noughties, some bright spark in MB’s body design team had A Good Idea. The Japanese car designers were doing well with the application of higher quality galvanising to metals in wet areas (cheap) without the need to apply special/ extra paint coats to those areas (very costly). So, MB sought to copy that lead. This was also at the time when the C & E classes saw a huge rise in volume, the E Class rose from 180k to 440k annual worldwide over about 5 years. Put both together and clearly Something Had To Be Done!

So, the body engineering team got to work. Could they be clever about the strategic placement and specification of galvanised steel parts vs paint application?

Quick technical note. Stone rash on wheel arches is solved in Japanese cars by the application of a clear dogleg decal of fairly thick (0.5mm) resilient plastic on top of the paint clearcoat. German cars don’t use these as they feel them to be ugly and less than premium. Also at this point, exterior styling was trending towards a more aggressive road presence, and an easy way to do that is with more pronounced wheel arches.

Add all of this together and you’ll see why the corrosion problem happened. The cars were pretty much designed to rust more easily, without much deeper engineering experience of galv application to corrosion prone areas which at the time, they didn’t have- driven by the need to control costs due to the rapidly increasing volumes generated by the global sales teams.

It should be pointed out that the Japanese experienced their own corrosion problems across the 60s & 70s. It’s nothing unique.

 

[ptruswell]

Great replies here. Thanks for everyone's response.

 

[rf065]

It wasn’t cut price steel. It also wasn’t as simple an issue as “use cheap materials” for MB.

Firstly. Daimler Group buy all of their commodity metals worldwide under a group purchasing scheme. The metals are bought to highly exacting specifications, and the Group is big enough to represent significant annual steel tonnage in its own right. Daimler buy primarily from the likes of Benteler, Artelor Mittal and ThyssenKrupp, companies not exactly known for shoddy materials.
Secondly, the process by which steel is made somewhat precludes “shoddiness”, as in if a mill is making high quality metals, they won’t (can’t) just stop and switch to making “cheap steel”. The steel is milled, processed and coiled like paper, all in a continuous process. Some mills only make exactly one grade of steel for this reason- they work to the volume limits of their capacity. So, the quality deviations in material that Daimler bought/ are buying to are minimal and subject anyway to Daimler’s own quality standards.

Now we come to the tragic bit, as the Engineer’s Song goes. At some point in the early noughties, some bright spark in MB’s body design team had A Good Idea. The Japanese car designers were doing well with the application of higher quality galvanising to metals in wet areas (cheap) without the need to apply special/ extra paint coats to those areas (very costly). So, MB sought to copy that lead. This was also at the time when the C & E classes saw a huge rise in volume, the E Class rose from 180k to 440k annual worldwide over about 5 years. Put both together and clearly Something Had To Be Done!

So, the body engineering team got to work. Could they be clever about the strategic placement and specification of galvanised steel parts vs paint application?

Quick technical note. Stone rash on wheel arches is solved in Japanese cars by the application of a clear dogleg decal of fairly thick (0.5mm) resilient plastic on top of the paint clearcoat. German cars don’t use these as they feel them to be ugly and less than premium. Also at this point, exterior styling was trending towards a more aggressive road presence, and an easy way to do that is with more pronounced wheel arches.

Add all of this together and you’ll see why the corrosion problem happened. The cars were pretty much designed to rust more easily, without much deeper engineering experience of galv application to corrosion prone areas which at the time, they didn’t have- driven by the need to control costs due to the rapidly increasing volumes generated by the global sales teams.

It should be pointed out that the Japanese experienced their own corrosion problems across the 60s & 70s. It’s nothing unique.

Sounds like a really good explanation except for one thing, when my 4 year old CLK rusted, it was not in the "corrosion prone" areas. It rusted along the painted side of the quarter panels and doors on the full length of the car (both sides). The boot lid was also rusting behind an area covered with a plastic moulding which had never seen daylight or anything else since new. It started as little micro blisters which grew under the paint until they popped open revealing rusty metal underneath.
It has been mentioned elsewhere that the metal used in these cars was faulty (cheap steel), it contained no copper oxide, due mainly to the price of copper at that time, one of the benefits of using copper oxide in metal is its ability to charge the metal and prevent rusting, ie prevent the metal from rusting within itself once the metal has been sealed with paint.

 

[Kev555]

No other word for it only shoddy and careless prep or no prep before painting, rusty water marks under the paint, dirt, grease and god knows what not. Last time I seen that shoddy prep was in agricultural tractors namely Fiat in the 80,s and 90,s. Body panels were painted in the same way with no rusty watermarks removed before painting or proper preps done. Tractors were famous for reliability but virtually rusted away before your eyes.These panels were painted by the same firm that painted body panels for Ferrari at the time

 

[peterws1957]

I saw many instances of imported high quality steel consignments being left open to the elements for whatever reason and rusting away. The default method to remove the rust was to "pickle" the steel, but I never knew how effective this was in terms of when it was used in manufacturing process.

 

[Kev555]

"These panels were painted by the same firm that painted body panels for Ferrari at the time"
Sorry meant to say the same company supplied body panels for Fiat tractors and Ferrari not painted. Does anybody familiar with Ferrari's know if they had the same rust problems?

 

[ptruswell]

My 2005 W211 estate had some stone chipping on the rear arch lip that had gone through the paint and the plating that looked brown. I just hose them out once a year and apply Dinatrol, seens to work there's been no progression.

Time to resurrect this thread and get an update...

My W211 estate rear wheel arch rust is blooming nicely but I think it is time to stop it making more progress (might also be too late!). Interested to see your use of Dinatrol - never heard of it but a quick Google tells me it is a "corrosion prevention" spray. Is it worth me trying this? All I am concerned about here is stopping or just slowing the progress of the rust - if I am able to put a bit of grey paint on it to tidy it up a bit then I might do that as well. I am absolutely not expecting to get this 'like new' again because that is not a priority, but I would like to do something to slow it down.

Any advice is again, most welcome

 

[Craiglxviii]

Time to resurrect this thread and get an update...

My W211 estate rear wheel arch rust is blooming nicely but I think it is time to stop it making more progress (might also be too late!). Interested to see your use of Dinatrol - never heard of it but a quick Google tells me it is a "corrosion prevention" spray. Is it worth me trying this? All I am concerned about here is stopping or just slowing the progress of the rust - if I am able to put a bit of grey paint on it to tidy it up a bit then I might do that as well. I am absolutely not expecting to get this 'like new' again because that is not a priority, but I would like to do something to slow it down.

Any advice is again, most welcome

Dinitrol is superb. It’s a spray-on liquid wax, penetrates and hardens then remains in the area. Also dispels moisture, so a must have for all MBs!

 

[Snake Charmer]

Time to resurrect this thread and get an update...

My W211 estate rear wheel arch rust is blooming nicely but I think it is time to stop it making more progress (might also be too late!). Interested to see your use of Dinatrol - never heard of it but a quick Google tells me it is a "corrosion prevention" spray. Is it worth me trying this? All I am concerned about here is stopping or just slowing the progress of the rust - if I am able to put a bit of grey paint on it to tidy it up a bit then I might do that as well. I am absolutely not expecting to get this 'like new' again because that is not a priority, but I would like to do something to slow it down.

Any advice is again, most welcome

Better condition than my '04 S211, mine will be needing new metal.

 

[Kev555]

Lanoguard is very good as well and the easiest of any underseal to apply

 

[mioba]

Done my W220 arches last year. body shop ordered new repair panels. cut out old metal and in with the new.
I had them painted 5 years ago - the rust will just return unless the rust it cut out. Its like a cancer - sad analogy.

 

[onefortheroad]

Time to resurrect this thread and get an update...

My W211 estate rear wheel arch rust is blooming nicely but I think it is time to stop it making more progress (might also be too late!). Interested to see your use of Dinatrol - never heard of it but a quick Google tells me it is a "corrosion prevention" spray. Is it worth me trying this? All I am concerned about here is stopping or just slowing the progress of the rust - if I am able to put a bit of grey paint on it to tidy it up a bit then I might do that as well. I am absolutely not expecting to get this 'like new' again because that is not a priority, but I would like to do something to slow it down.

Any advice is again, most welcome

Very common on the w211 . I'd have it tidied up and a vinyl wrap put on around that area . Mb went on to putting a small patch of vinyl in that exact area, for I suppose the rusting issue , it's apparently to do with the aero dynamics and how all the road dirt is pushed down and around that area. When I owned my w211 luckily it was black ,so every 6 months I'd apply underseal on the first 10 inches of the arch inner and outer . The exposed section I applied a clear wrap .

 

[horatio]

Time to resurrect this thread and get an update...

My W211 estate rear wheel arch rust is blooming nicely but I think it is time to stop it making more progress (might also be too late!). Interested to see your use of Dinatrol - never heard of it but a quick Google tells me it is a "corrosion prevention" spray. Is it worth me trying this? All I am concerned about here is stopping or just slowing the progress of the rust - if I am able to put a bit of grey paint on it to tidy it up a bit then I might do that as well. I am absolutely not expecting to get this 'like new' again because that is not a priority, but I would like to do something to slow it down.

Any advice is again, most welcome

It still looks solid? I would grind back to clean metal using a dremel and repaint the usual way.

If you can’t get it back to clean metal I find POR15 works really well provided it’s been prepped properly with the metal ready etc.

I did the POR15 ‘bodge’ on my dad W211 years ago and it’s holding up fine. Lives on the cost too so it’s well tested. If it’s just the inner lip, a touch up stick over the top results in an unnoticeable job.

Key is to nip it in the bud early

 

[Craiglxviii]

Very common on the w211 . I'd have it tidied up and a vinyl wrap put on around that area . Mb went on to putting a small patch of vinyl in that exact area, for I suppose the rusting issue , it's apparently to do with the aero dynamics and how all the road dirt is pushed down and around that area. When I owned my w211 luckily it was black ,so every 6 months I'd apply underseal on the first 10 inches of the arch inner and outer . The exposed section I applied a clear wrap .

It’s quite common for either black vinyl patches or clear thick PC coupons to be placed at wheelarch/ fillet areas at the factory on certain cars for this reason, stone/ grit rash leading to rust.

 

[ptruswell]

Dinitrol is superb. It’s a spray-on liquid wax, penetrates and hardens then remains in the area. Also dispels moisture, so a must have for all MBs!

Thanks for your response - which particular Dinitrol product do you recommend? There are a few but this one caught my eye:

DINITROL RC900 RUST CONVERTER & PRIMER 400ml AEROSOL​

 

[ptruswell]

Again, great responses. Thanks all

 

[Craiglxviii]

Thanks for your response - which particular Dinitrol product do you recommend? There are a few but this one caught my eye:

DINITROL RC900 RUST CONVERTER & PRIMER 400ml AEROSOL​

The one I use is Dinitrol-ML.