Found 2 rusty funny looking “washers” on bolts holding on front wings, W216 CL 500, can one just undo these and replace?

[Submariner1]

Bit odd ... found both these washer things had got rust on them. Both sides.



OK no biggy as they are holding down an Aluminium front wing flange, and its really only surface rust.
Question: can one just undo the Hex Nut and remove the washer, and not disturb the wing position if you hold the Star bolt at the same time?
Don’t want to disturb the perfectly aligned wings.
Failing that :
Anybody know a good rust converter?
I tried NEUTRARUST 661 ... on the shaft of my Rotary weed and feeder ..... Utter crap. Yes it ‘converted’ the surface rust, and left a sort of plastic like black like coating. but when I replaced the shaft, the black plastic coating scraped off, revealing totally rusty shaft. Totally useless as you think you have cured the rust, but it would just be festering under this plastic like finish.

Unlike the Brilliant Trustan 23 (sadly no longer available), that really converted 100% of all surface rust, at a molecular level, and never returned.
And didn’t add surface height ... perfect for painting.

Maybe I should use a Rust Remover?. , as I prefer it doesn’t leave a coating depth ref painting.
Any recommendations ?

Weird these washers both rusted, as the only other rust on the car (even underneath) was the Electronic Brake Shield, and the tie bar holding the 2 exhaust pipes together near the diff. And they were near or tied to the exhaust pipes.
Being OCD both now replaced, and the new parts given an additional 2 spray coats of heat resistant paint and lacquer, and they still look brand new 2 years later

 

[LostKiwi]

I'd imagine that's a captive bolt with a torx head to assist if it's tight.
Yes you should be able to simply undo it.

 

[Uncle Benz]

I reckon you’ll find that “washer” is integral with the nut. The reason for corrosion is likely differing metals. You should be able to remove one at a time, soda blast and paint both sides and refit. It’ll leave a witness on the panel below so you can put it back in exactly the same place

 

[Submariner1]

I'd imagine that's a captive bolt with a torx head to assist if it's tight.
Yes you should be able to simply undo it.

Thanks much appreciated

 

[Submariner1]

I reckon you’ll find that “washer” is integral with the nut. The reason for corrosion is likely differing metals. You should be able to remove one at a time, soda blast and paint both sides and refit. It’ll leave a witness on the panel below so you can put it back in exactly the same place

Good point, I hadn't checked if wiz gives me a torque setting