Stopping rust along quarter seam - 98 Explorer

Is there any way to slow down or stop the rust in the fender to quarter edge seam without having to tear up the paint?

It looks like from the inside the butyl caulk is in the way of spraying anything in to treat it. Should I dig out the caulk and use POR-15 in there?

There is some rust starting to appear along the rear quarter seam at top of the wheel well. It looks like the seam was puckered and a little salt got in between the quarter panel and the inner fender panels and now it has started to bubble through the paint. In another year it will be a big ugly mess.

 

[MONMIX]

for starters STOP and SLOW DOWN are two totally different things in the world of rust.

STOP: No, there is absolutely NO WAY to stop it with out getting into the paint. It will never happen.

SLOW DOWN: slow down as in buy your self a few months? or a few years ?

Simply put rust is an evil biotch. It never sleeps, it never goes away. More over its often pretty unpredictable. Yeah you can soak the inner quarter with one of any number of rust treatments, that might get you a few months or a few years. On the explorers the rust on the quarters and the rockers generally is coming from the inside out. It could be kinda ugly underneath, or it could be super dooper ugly underneath.
Good luck. I hope I didnt discourage you too much.

 

[Dave98XLT]

I was thinking about digging out the caulk in the quarters from the inside and coating with POR-15. http://www.por15.com/

Instead of body work to repair the holes, they are small enough where I might cover them up with a wheel well trim moulding. I don't like stainless as much as rubber but it won't be an eyesore.
http://www.##################.com/sku/Putco/Fender_Trim/P4597206.html


The rockers are completely gone in the rear as the salt entered via the moulding attachment holes. However the moulding still covers them.

 

[Onuma]

I was thinking about digging out the caulk in the quarters from the inside and coating with POR-15.

I have an old '66 GMC pickup on which I've been working as a hobby, as well as my daily driver '04 Explorer.

The former has rust for miles, while the X has quite a bit of its own over the rear passenger wheel -- all around the gas fill cap area. I will have to cut out the entire quarter, from the front of the rear wheel well to about 6-10" behind it, and possibly as high as the rear glass. It's going to be a nightmare which I won't be keen to try again.

That being said, I've done quite a bit of homework on which rust-prevention (or rust-retarding) coatings would work better in my situations.

POR-15 is effectively a layer which covers the top of the metal, trapping in the rust and keeping further contaminants out...for a time. Eventually, the edges will begin to peel away, chip, and rust will creep underneath the coating. It may take some time, or it may start in as little as a couple of months. It all depends how well the edges are dressed up when it is applied.

Many others who are familiar with POR-15 recommend different products, such as Zero Rust or Eastwood Rust Encapsulator. They're generally less expensive, easier to apply, and don't tend to peel up on the edges. I've heard the best things about the Eastwood coating from a few different blogs & magazines, including one where the writer used a side-by-side comparison against POR-15 (ol' reliable) on the same hood, leaving it out in the elements for several months.

I don't know if you've addressed your rust yet, but I hope this helps for the future.