And so it begins.. tackling r230 wheel arch rust.

[Conor]

So..

I have been super keep to get eyes on the full extent of the rust on my r230 wheel arches.

So today I went about removing the wheel arch liners and also the rear bumper. The bumper was needed to be removed as some of the rust had made its way into an area covered by the bumper.

Judging by the timestamps on my photos it took about 3.5 hours to remove both arch liners and also the rear bumper. A significant amount of that time was taken by figuring out the boot trim removal.... so basically to get at some of the bumper fixing, basically all the boot trim needed to come out and was complicated by the roof mechanism. Some times I needed to part open the roof to get at bits, then close and later on part open again.

I have seen guides online where you part open the roof then open the boot lid and support it with some jack. That wasn't practical for me, just because it wasn't, but also - the boot wouldn't actually open by the "emergency key".. which is a wee bit of a concern in it's own way.

It was a fun ride and gave me more of an insight into the roof mechanism and the various rubber seals etc.. Will be great to get them all covered up in Gummi Pflege and I can also give the car boot a good vacuum and clean.

On a side note.. one of the the paddings (marked with masking tape) was a little damp. when I took it out. Note that there was NO water anywhere else in the boot and no real signs either which is a little amazing really. I know the last owner didn't store it in a garage either.

More pics will follow in another post as you can only add 10 per post..

 

[Conor]

"Instructions for boot removal, please see post #23

 

[ajlsl600]

Wow, wot a drama, just to get at arches... And wow again there's 3 x rust there as on my 01 clk! I first got at mine about 6 yr ago and each 2 yr since you never at that stage get rid of it, more like control. I catch mine before it gets to spider or blister, downside color match ain't perfect but I can live with that.....

 

[grahamcol]

Wow. There's some significant rusting there. Shameful on any car let alone a Merc. I'm interested to see how you get on with this project.

 

[peterws1957]

It's a shame that these suffer from such a basic design fault. Don't be tempted to cover the rust in one of those converter products and paint over- it never really works.

 

[alexanderfoti]

Hmm yea no ideal, that level of rust would be best dealt with at a bodyshop, as the repair will come round the side need to be painted/blended into the rear quarters.

 

[LostKiwi]

Agree with Alex.
That looks a little too much for a home repair.
You didn't leave yourself much room behind the car to work on it!

 

[Conor]

Hey guys,

Yes it certainly is a drama alright.. I was just keen to get stuck in and see the full extent at the rust. I'll have a go at clearing off the rust with various attachments on a dremel and I also have Bilt Hamber remover and "converter".. but the main aim is to get the vast majority of the rust off.

I don't plan on painting it myself as I will get a professional to do that.

I may be a bit premature with the next statement but I don't think the rust is as bad as it looks. That is solely based on the fact that any part of the lip that I pulled very hard at, didn't break away.. I could only really get the flaked paint off.

I will use the rust removed to get off as much rust as possible after using the wire brush on Dremel... then when i've gotten as much off as possibly by physics and chemistry i'll just coat all the areas in the hydrate 80, which is like a final converter and sealer.

The next part is very much a maybe.. depending on how I am feeling..

Sand down and prep with sanding and a bit of filler (if needed)..then potentially some kind of epoxy primer + a spay of some paint to seal it up to save the job before it get's to body shop.

Body shop can then prep the surfaces further as they see fit and spray.

At any point along the job I can just down tools and take to a body shop so I am not worried.. And at the end of the day, by the time I am finished with the above rust removal/treatment. I would theorise that any rust that comes back will come back slowly and creep in. I can monitor the situation closely.

I'm trying to balance between my eagerness to learn about all this and getting it all done by a professional.

 

[Conor]

For the avoidance of doubt.. I am in the same boat as you guys that figures this will end up going to a professional to get finished/done but I'm going to have a bit of fun working on it in the interim. I need something to keep me sane right now..

 

[LostKiwi]

I need something to keep me sane right now..

And you chose to work on an r230 to keep yourself sane?

Things are clearly worse than we thought!

 

[Conor]

And you chose to work on an r230 to keep yourself sane?

Things are clearly worse than we thought!

Just goes to show the other stuff I working on :/

 

[Conor]

Broke out the Dremel today and tried out 3 attachments for the rust removal.

1. Wire brush head - Was very effective at cleaning up and smoothening the surface but didn't make the metal clean looking. All the bristles came off in a couple of minutes too. Not sure if that was because it was a cheapo bit, pilot error or what. Skip - there aren't enough of these bits in the world.
2. Stone grinding disc - Was somewhat effective but gave a kind of uneven finish.
3. Fiberglass cut off disc - This was the most effective but time consuming to get the finish. It was the best at bringing to bare metal but I wonder if it is deforming the shape of the arch a bit much. I guess it can't be too much as the tool has very little impact in general.

Later, I will order one of those "scotch brite" type discs and see how that goes. I suspect it will offer similar results but in a faster and less impactful manner - i.e. Less risk of gouging the surface.

I have signed up to another forum, more dedicated to dedicated to body work which should help me learn about the finer details and pitfalls etc.

Right now this is somewhat enjoyable and reminds me of my model plane building days. I'm spending more time on the computer researching, than I am at the car. If it starts to get stressful, i'll just give it to a body shop

Bit of a photo dump here.. Not a huge amount to see today.

The eagle eyed will notice a lot of debris from the grinder on the "good" paint. I washed this off by pouring water on it after. I will get some plastic sheeting from screwfix before going at this again.

 

[badger_wazzala]

Looks like you've found a cure for your boredum indeed.

I've treated surface rust with hammerite kurust before following a good deal of sanding. It alters the chemical reaction/oxidation but I'd say for your arches it would be better to have a bodyshop cut out the rust and fabricate/paint so you don't feel like throwing yourself under the car when rust spots re-appear.

The angle grinder disc you should be using is a flap disc. Using a cutting disc won't do you any favours at all.
E.g. https://www.screwfix.com/p/erbauer-zirconium-flap-disc-115mm-120-grit/4147g

Be careful with the rust spots flying from the cutting/sanding disc that are now covering your paint, if they are hot they will land and stick to the paint and begin to rust very quickly. Use some resin polish straight away to remove these.

Your inner arches/wheel wells seem to look in good fettle, are all Mercs undersealed from factory?

 

[LostKiwi]

A flapper wheel on a drill is usually the way to attack this type of damage.
Something like this:

https://www.toolstation.com/abracs-...8cxdvMSx-d2S4EcVSJIUSUwHFuX8JzCYaAv6kEALw_wcB

 

[Conor]

Looks like you've found a cure for your boredum indeed.

I've treated surface rust with hammerite kurust before follwoing a good deal of sanding. It alters the chemical reaction/oxidation but I'd say for your arches it would be better to have a bodyshop cut out the rust and fabricate/paint so you don't feel like throwing yourself under the car when rust spots re-appear.

Are all Mercs undersealed from factory?

Haha perhaps, although i've not been bored lately

Yes if you look above you will see I have both remover and converter from Bilt Hamber. I plan on physically removing as much as possible, then treating with the chemicals.

I don't think this rust requires cutting out really as it is just surface rust. I will know more when I go at the "lip" part and see how deep the rust is... but I have pulled at it pretty hard and the lip didn't break off.

I'm not sure this is an under sealing issue. It seems to be more of a design flaw. The arch has a lip in it, which holds dirt/silt/mud kicked up from the wheels. Moisture is then drawn out of this deposit and into the paintwork, bringing us to where we are today

 

[Conor]

A flapper wheel on a drill is usually the way to attack this type of damage.
Something like this:

https://www.toolstation.com/abracs-...8cxdvMSx-d2S4EcVSJIUSUwHFuX8JzCYaAv6kEALw_wcB

Oh yes, forgot to mention that actually. I have some flapper discs in another set that I will try out next time. Thanks.

 

[Kev555]

I done the Vito rear arches last OCT, buffed them back to clean metal inside and out. Kurust treated them, coat of primer and coat of 2 pack paint through the spray gun. Good layer of waxoyl on inside of arches and they are blistering again

 

[Mike Mil]

Really enjoying this thread as it's something I need to do on my wife's SL. Really interested if you have any further details on getting that bumper removed. I have seen the video online with the opening of roof and hood and not keen as I too see to have problems with the emergency key. Also don't want to leave the roof open while I take my time to get sorted. How did you manage to keep the roof operational?
many thanks

 

[peterws1957]

A Dremel isn't powerful enough to deal with this extent of rust - use a wire wheel on an angle grinder, very effective in removing rust but you have to use face protection, because you'll find wire spikes in your skin otherwise. It won't remove solid metal either like grinding does.

Rust converters don't work in the long term in my experience, but it depends how much work you want to put in. I've used converters to turn rust pits black to identify where more work is required. You can use a Dremel to remove the final pitted areas. Done this many times on 50 plus year old cars and the rust has never come back.

What I wouldn't do is to allow a body shop to deal with rust, unless they are cutting out and welding in panels. Your approach is the best - do all the prep and get final work done by a painter.

 

[Wighty]

Excellent Connor , I like your approach as that is what I would do as well . Try as much as you can and learn along the way and at any point you can’t progress further hand it over to the pro’s .
It costs you very little apart from time and some tools which will always get used in the future .
I must admit I would have gone cordless angle grinder from the start , I never find my dremmel up to much unless it’s very small and detailed .
I can vouch that wire wheels break up hit your skin and make you bleed , it happened the other week cleaning up my brake hubs
Keep up the good work , love the thread and the pics , thanks for taking the time to do it