IJM

I've got some rust in the rain gutter above the front passenger door that I'd like to address before it gets worse. I could slap some silicone on it, but I suspect that's not a great long-term solution.

Any pointers?

may pop

The rust will need to be sanded or ground out. The seam sealer in the groove may have rust growing under it also.
Next the rust needs to be killed or neutralized. Then an epoxy primer and top coat.

Ron

Phydeaux33

Before starting the rust abatement you'll need to remove the gutter trim, after that the may pop's advice. Here is a link to removing the gutter trim.
https://www.google.com/url?sa=t&sour...U0Yl4kqx3f-T4J

robsjeep

Many silicone RTV produce acid upon cure (acetic acid) dont use silicone rtv on bare steel or rust unless you know it is acid free.

There are much better alternatives. heck jb weld it! but you got to remove the rust, and or treat it with rust converters prior to that.

Urethane chault usually is prefered if you want a flexible caulking that is acid free. but you need to kill the rust first


yes the trim must be removed for effective repair.

avoid the silicone

may pop

Here is one of many products the will help kill the rust.

may pop

Top picture product was less than 15 bucks. From Auto Zone
This one was under 50 bucks from Amazon

may pop

If you don’t use a product like these the rust will continue to grow. Next top coat with an epoxy primer and then a color coat.

Good Luck
Ron