Rust on van , differing opinions. What would you do?

[Dylan T]

Hi all - I have a Citroen Relay van that I'm currently converting into a camper, and over this year some rust has progressively got worse along the top of the stainless door runner. I bought it as an ex fleet vehicle that had been sitting during covid and my guess is that it was resprayed in a rush and I didn't spot it, and it's now coming back (you can see the touch ups in some of the photos I've attached). It looks like standing water between the rail and the body have corroded over time (not sure how but hey ho). The rail can be taken off from the inside and thankfully I haven't got too far on the camper so still have access - but it is a ballache to do, and I'm wondering how far I go with this before I reach a stage where I can't access it at all due the camper walls and furniture being up.

I have no real proper bodywork experience or the gear, so this would be a case of me taking it somwhere but I was hoping for some advice from some kind folks before I do so I know what to ask for or expect.

I've spoken to two companies so far; 1 said that they'd just use a Dremel and remove the rust and respray it and there's no need to remove the rail. They've said that once they had a bead of silicon along the top of the rail the water won't get down so if there's any existing rust down there it won't get worse as it won't get wet.

A second I've spoken to said the rail needs to come off and the while thing needs sanding back and respraying (we have no way of knowing if there's rust behind the rail).

It's worth noting that it's possible that i'll be wrapping this portion of the vehicle with vinyl, so I'm wondering how necessary a respray is. Or, even if I could just sand the rust parts flat, put vinyl over and reseal and leave it knowing it won't get more wet.

Would love to know some opinions on this - thanks so much. And apologies for state of van - it's very dirty, it's just the rust bits that are the issue, the rest is just me being too busy to give it a proper clean!

 

[Lower]

The rail needs to come off, the rust removed and then repainted.

Just sealing in the rust with paint or silicone won’t stop it spreading under the paint.

 

[freddiemercurystwin]

Yes as above, I bet the OP already knows the right answer.

 

[Belle427]

Id agree, the surface has to be prepped well even for wrapping.
In my experience the rust will always return unless done properly which it very rarely it is.

 

[Dylan T]

The rail needs to come off, the rust removed and then repainted.

Just sealing in the rust with paint or silicone won’t stop it spreading under the paint.

Yes as above, I bet the OP already knows the right answer.

Id agree, the surface has to be prepped well even for wrapping.
In my experience the rust will always return unless done properly which it very rarely it is.

Thanks all - sounds about right. Any one fancy guessing a price I should be expecting?

 

[Belle427]

I would guess a roof re paint in our current climate to be near £500.
Used to be around £300 before the world went mad.

 

[Avocet]

What you're seeing is "galvanic" or "electrolytic" corrosion. You get it when two dissimilar metals are in contact. Sainless is vicious to mild steel if there's an electrical path between them.

As others have said, you need to take the runner off, and treat the rust. When you've done that, you need to re-assemble it in such a way that there s no electrical contact between the two - which can be quite had to do properly. You would really need a thin layer of plastic or foam, like double-sided tape) between the runner and the paint, then plastic washers behind the fasteners, etc.