CLK W209 Sport Calipers - Piston Slightly Damaged

[psyq321]

I bought a pair of MB sport calipers for W209/W203 from ebay.

Before fitting them, I decided to clean them and make sure everything works OK (so I ordered pins/springs and dust cap from MB - unfortunately I cannot find the damn seal part #s, they are not in EPC)

Calipers are standard sport pack for W209 200K or standard calipers for W209 350 - A 003 420 36 83 and A 003 420 39 83

So, after inspection (by removing pistons and cleaning) - I noticed that one piston is slightly damaged It is not from the outside, so in theory the piston should work - but I am worried that the corrosion will spread slowly and, at some point, seize the piston..

Since I'm living in Germany currently, and drive 75 km to my office at least three times a week, over a highway with no speed limit (nice fine patches of ~20km I drive 200-230 km/h) I really don't want to end up with messed-up brakes...

What do you think? Pictures attached.

Unfortunately I cannot find anyone who sells pistons alone - the best solution would be just to buy the damn piston, seal and replace the broken one, but it looks like nobody sells the pistons alone

Thx in advance!

 

[Aoraki]

Personnally I don't think there would be a problem with that piston, I would run with it.

 

[Midland45]

Looks like very superficial corrosion to me, on what is essentially a huge chunk of metal. Doesnt look like anything major going on such as cracks etc, which could ultimately mean scrapping the piston. As long as the surface is flat, the obligatory smear of copper slip grease will stop any further corrosion in its tracks.