wheel arch rust bubbles

[nutrunner]

hi all ive noticed that my clk 320 has started to get a few rust marks on my rear wheel arches whats the best way to prevent this i regularly clean under the grooves

 

[Mike Walker]

IMHO you won't prevent it until the rust is removed/treated and a proper respray job is carried out. My C Class W203 2001 vintage had the rear arches dealt with twice courtesy of MB 3 years ago but the rust still returned. Depending on age of your car you could have a similar problem with inadequate galvanizing if there is any at all.

Cleaning out the arch lips regularly helps but.........

 

[optimusprime]

i know

Only way is to have it cut out. I have this 260e 25 years old with rust in bottom corners of wings .It will go in next year to have it removed .After the winter ,wont have it done this side of crimbo.

 

[cb1965]

IMHO you won't prevent it until the rust is removed/treated and a proper respray job is carried out. My C Class W203 2001 vintage had the rear arches dealt with twice courtesy of MB 3 years ago but the rust still returned. Depending on age of your car you could have a similar problem with inadequate galvanizing if there is any at all.

Cleaning out the arch lips regularly helps but.........

This ^^^^ Needs a proper back to metal restore job doing sadly! Anything else will just be a cosmetic makeover that will not last!

 

[simon1966]

This ^^^^ Needs a proper back to metal restore job doing sadly! Anything else will just be a cosmetic makeover that will not last!

Exactly!

It is a very common problem, I know yours is a CLK, but just about every 211 E class I have seen has this problem on the rear arch flanges. Is it confined to the flanges or does it extend to the outer arches?

Mine had started to show some very light corrosion on the flanges, I had them dealt with and nipped it in the bud as such. Back to bare metal, protection and proper paint job. I have heard about others doing it with hammerite if confined to the flanges, which I'm sure will work well but maybe not look quite as good

 

[serndipity]

Several years ago, the upper section on both of my rear wheel arches, on my 2001 CLK cabriolet, developed bubbling of the paint.

I thought it to be due to underlying rust and took it to a high end auto body shop for repair.

The good news was that it turned out there was no rust......just bad paint. The shop could not pin point why this happened, maybe poor factory pre-paint preparation in those areas?

The bad news was that the cost to repair was nearly the same, as had underlying rust been the cause.

 

[dhk284]

I had to change both of my wings and sort out the rear wheel arches after taking the metal all the way back, I used a chemical product that turned the rust really hard then I used a chemical metal compound rubbed that down then used a filler, at the back of the arch I used a wire brush dried it and used a water proof sealent all the way round to seal it. then I got a friend of mine to spray them. It worked for me hope it works for you. Lots of work.

 

[chizzel89]

You can repair even badly pitted wheel arches so well that the rust never comes back, but it is quite meticulous process and is time consuming. Also you need to use the right chemicals and paints.
Bilt Hamber do a rust removing Gel which actually leaves shiny bare steel and will even remove all the oxides from the bottom of deep rust craters, meaning you can save those well fitting genuine MB front wings, and likewise save the rear wheel arches without having to cut it out and then have the hassle of trying to get the right profile on the repair section.
Couple the rust remover with their rust killer/ barrier system, coupled with a couple of coats of their Electrox primer (90%+ zinc solids) and you will have removed/ neutralised every molecule of rust, reinstated an etching primer with the barrier system and then effictively galvanised it as well. I did this on my W202 front wings 3 yrs ago and there's not a sign of any rust coming back, and they even had a few pinholes the rust was so bad.

 

[Dieselman]

You can repair even badly pitted wheel arches so well that the rust never comes back, but it is quite meticulous process and is time consuming. Also you need to use the right chemicals and paints.
Bilt Hamber do a rust removing Gel which actually leaves shiny bare steel and will even remove all the oxides from the bottom of deep rust craters, meaning you can save those well fitting genuine MB front wings, and likewise save the rear wheel arches without having to cut it out and then have the hassle of trying to get the right profile on the repair section.
Couple the rust remover with their rust killer/ barrier system, coupled with a couple of coats of their Electrox primer (90%+ zinc solids) and you will have removed/ neutralised every molecule of rust, reinstated an etching primer with the barrier system and then effictively galvanised it as well. I did this on my W202 front wings 3 yrs ago and there's not a sign of any rust coming back, and they even had a few pinholes the rust was so bad.

How did you get the Hydrox rust remover to work satisfactorily?

 

[mbmark79]

Any idea how much this kind of bodywork restoration costs? Just bought a 2000 e class this morning with bubbly arches

 

[chizzel89]

You won't really get a commercial bodyshop to do that kind of work atleast not for a reasonable price. It gets the car out of their workshop quicker if they cut it all out/ replace panels.
IF you have a second car, you could do all the stripping back/ rust killing/ primering yourself as there is no real skill to that- just following instructions and then get a bodyshop to do the re-painting and rust proofing. Most won't offer a warranty on corrosion repairs (I.e not replacing the panel) so most won't mind rubbing down and spraying something someone else has prepped/ treated.
Dieselman- the key with the Deox Gel is to obviously full isolate the corrosion, scalp the worst of it with a flapper disc, then apply around 4mm covering of the Gel using an old credit card or suchlike, then gently lay clingfilm over it.

Then you can leave It for 24 hrs, wire brush it, wash it, dry it and then re-apply.
After 2 applications, if there is still some black oxides at the bottom of the craters you can probably leave it. It will be well and truly converted to iron phosphate. Generally though it leaves shiny steel.

After washing it the last time I dry it with a hot air gun. The now empty craters can trap a lot of moisture!

 

[chizzel89]

I should add that if the seam of the rear arches has swollen etc then you will have to cut it out and weld in new metal. It's almost impossible to fully get rid of the rust from a seam, though you can go some way to a semi long lasting repair with a sharp pick / hook tool to dig it out with, then chemically remove/ treat the corrosion.