FJ rims for a 4Runner - your help needed

[m@x]

Yesterday I drove 600km to purchase almost new FJ rims for my 2006 4Runner.
The rims are in great condition, factory paint, just a couple of scratches here and there, but I am not concerned too much about scratches since I will be plasti-dipping the rims. I am also planning to mount brand new Coopers AT3 on them next week.

Today I noticed that 1 of 4 rims has an imperfection - the inboard flange of the rim has a thin but long (200mm x 0.4mm) line of bubbled paint on the inside of the flange. This is the area where a black compound is applied to stick the tire to the rim.

Refer to the pic below. In red - the affected area. "street >>>" indicates the part of the rim facing the street when the wheel is mounted.



Original pic is not mine and it is not an FJ rim. It was taken from here:
http://roadtraveler.net/wp-content/uploads/2012/03/17-inch-RW-TRD-1500.jpg

My questions are:

1) Is this an important contact area that needs to be repaired before the black compound is applied and the tire is mounted? Should I sand the bubbles off, clean and polish until it is smooth, maybe protect it, prime it, paint it?

2) If you try to remove the bubbled part, you can find some sort of white powder or dust under the paint. What is that?

Thanks!!!

 

[SSt4r]

I'll answer 2) - It's corroded aluminum (similar to rust with iron).

 

[jdkilroy]

What I would do: go ahead and sand the affected area(s) and check all the other rims for similar issues. After achieving a smooth finish on all surfaces where the tires contact the rims, wipe everything down with a clean rag wetted with turpentine. (I would use wet/dry sand paper that is 200 grit or finer after cleaning off the coarse surface corrosion)

Get a can of self-etching primer (Rust-Oleum makes a good one) and prime the inside surfaces of the rims. Allow to dry for min 48 hrs.

Mount tires and enjoy.

Hope that's helpful.

 

[Swimmerboy2112]

No big deal. Quite a common occurrence in areas that use salt to melt the snow and ice on the roads.

Lightly sand down the area and re-prime. No biggie.

 

[m@x]

Thanks everyone!

Can you guys give me some suggestions how to "re-prime" correctly?
Do I need to sand the area to the bare metal? is it ok if the primer also goes over the pained area around the bare metal or I have to mask the spot very precisely? What primer? is it fine to prime and not paint?

thx