Mercedes w202 underseal

[MilesMurphy]

Hi,

Does anyone know the factory underseal name or brand or can recommend an underseal close to its texture?

Thanks

 

[Wighty]

Hi,

Does anyone know the factory underseal name or brand or can recommend an underseal close to its texture?

Thanks

No idea but have a read up on “Dinitrol “

 

[rifiki]

Had my CLK rustproofed with Dinitrol around 10 years ago, still good

 

[Wighty]

Had my CLK rustproofed with Dinitrol around 10 years ago, still good

I’ve always got a can of the cavity wax in the garage , whenever I take a wheel off I always end up spraying some on something.

 

[Craiglxviii]

I’ve always got a can of the cavity wax in the garage , whenever I take a wheel off I always end up spraying some on something.

I “mistakenly” bought a six pack of it. The mistake was that it arrived as two six packs!

 

[daveenty]

Hi,

Does anyone know the factory underseal name or brand or can recommend an underseal close to its texture?

Thanks

I used Tetrosyl stuff when I was going through my W201 a few years back.

It's not exactly the same, in that it's a little more flexible and doesn't crack like the factory stuff, but it can be brushed on to give a finish like the original, or stippled. A light coat of paint to finish and you couldn't tell where I'd been with the new metal.

 

[MilesMurphy]

So if I was to clean up the rust, treat it, then rust prime those surfaces.

After that jet wash and steam clean the areas that are ok but are dirty, Allow it to dry.
Can I spray over the old underseal? Or should I remove it. If so how?

 

[ajlsl600]

I’ve always got a can of the cavity wax in the garage , whenever I take a wheel off I always end up spraying some on something.

Same in recent times... yrs ago, cos it was free from work, I used the stuff that makers use to seal in machine shop bar stock 2 afternoons s under Ford with press washer at work then when proper dry warm the stuff up. Sprayed whole under car and inside sills x members, dripped for day then hardens orangey / yellow can almost see thru it. That was end of any treatment during my ownership

 

[JoeHorner]

Dinitrol.

About 12 years back got given a Daf 32 (1966 belt drive jobbie) that had been sitting in a garage since 1971.

Floor pan was solid surface rust from front to rear but no holes. Wire brushed it, sprayed it with Dinitrol, and drove it as a daily for about 4 years on Anglesey (surrounded by salt water).

No issues at all apart from re spraying a couple of patches around the 3 year mark. You could see when it needed a top-up because the translucent brown started to turn a lighter orange as soon as anything started underneath.

Much better than underseal hiding what's happening until there's a hole!

 

[MBW201]

Here is my suggestion to everyone, you dont need to worry about what is there from start and you keep all bolts ready for removing. https://www.fluid-film.com

 

[mioba]

Seems a US based product

 

[charlysays]

These days the best thing to do with underbody corrosion is start with a thorough degreasing until there's no trace of dirt or oil, bilt hmaber surfex HD is good. Then go in with a needle scaler. This will find anything which needs welding, strip back underseal and achieve st2 surface prep on its own.
Then using straight bristle wire wheels at low rpm from various angles (I use a right angle air drill and sometimes even a flexi drive for difficult areas), finally finish with a thorough DA (I use a mini air DA) with 40grit and/ or 40-80 grit hand sanding (abrasive sponges are pretty good) to achieve a really good scratch profile- this will achieve st3 surface prep. Use sanding to blend into areas of remaining OE coatings and scuff these with 180g.
Two coats of epoxy mastic is your best bet, worked in thoroughly with a brush. You can go over that with an underseal of your choice.
To achieve a 202 merc OE look I think you'll need some kind of two part spray sealer.
Personally I left my epoxy mastic uncoated under the car and it's holding up fine. I did give it a coat of dynax UC as belt and braces but the shutz went in the bin. Awful stuff.

 

[Alastairp]

I had my 2005 CLK with only 6000 miles on it professionally Dinitroled in 2021 - it went back in for an annual check late last year and had a little remedial work done to the rear subframe area.

I had my new-to-me 2012 R230 with 38,000 miles done last summer - some pics attached:

All covers removed for preparation - steam cleaned/ masked, degreased & needle scaled where required:

 

[Alastairp]

And then Dinitrol treated:

 

[Alastairp]

Work was done by Preserve and Protect near Glasgow for £700 plus VAT

Car Rust Proofing In Scotland & Beyond - Preserve Protect

Car Rust proofing in Scotland. Waxoyl, Dinitrol, rust buster, located Johnstone, Glasgow. Contact us now.

preserveprotect.co.uk

There was a bit of rust on the inside lip of the rear wheelarches - they didn't want to do anything with it as they reckoned it would just come back in time.

I ended up doing it myself - cut off edge of flange then digging out the seamseal compound within the fold between the wing and the lip - grind off surgace rust using dremmel tool with various attachments - several applications of rust converter - several applications of degreaser and passivation chemical - two coats of silver epoxy mastic which is very close to silver paint colour - final application of MB touch up paint to blend in with existing

May well not last, but worth a try before going to the extent of cutting out and letting in new metal with consequent painting of rear wings.

 

[charlysays]

Work was done by Preserve and Protect near Glasgow for £700 plus VAT

Car Rust Proofing In Scotland & Beyond - Preserve Protect

Car Rust proofing in Scotland. Waxoyl, Dinitrol, rust buster, located Johnstone, Glasgow. Contact us now.

preserveprotect.co.uk

There was a bit of rust on the inside lip of the rear wheelarches - they didn't want to do anything with it as they reckoned it would just come back in time.

I ended up doing it myself - cut off edge of flange then digging out the seamseal compound within the fold between the wing and the lip - grind off surgace rust using dremmel tool with various attachments - several applications of rust converter - several applications of degreaser and passivation chemical - two coats of silver epoxy mastic which is very close to silver paint colour - final application of MB touch up paint to blend in with existing

May well not last, but worth a try before going to the extent of cutting out and letting in new metal with consequent painting of rear wings.

Many epoxy mastics are designed to be applied over steel with some residual corrosion in craters etc without it causing coating failure.
Even so it's best to try to get rid of as much as possible.
Good job hooking out all the seam sealer behind the lip as this always hides some corrosion. Scraping out the seam with something sharp then attacking with a straight bristle wire wheel is good too.
To completely remove rust from craters, back to clean grey steel, bilt hamber deox gel works wonders. I usually do what I can with power tools like needle guns and wire wheels then give it 24hrs with deox gel and there's then no visible rust remaining.
The epoxy mastic I use is called Jotamastic 90 Alu winter grade and minimum surface prep is ST2 standard (quite a lot of remaining visible rust), I always aim for the more rigorous st3.
I think if it's prepped in accordance with your paints spec sheet, is fully coated and then wax injected from the other side, it'll last a few long time, many years.
The wheel rear arch lips on my old Merc were badly pitted and even needed some welding where the sill end / arch lip meets the plastic sill cover and they are still perfect 5 years later so it is possible to get permanent repairs even where surface rust has become quite advanced and even got into the seam to some degree.